Ye Tian: Surveilling stress to live longer

Ye Tian investigates how mitochondrial stress signaling pathways regulate longevity using C. elegans as a model system.

An avid reader, Ye Tian used to save up her child allowance with the sole purpose of buying science fiction books. Reading and solving mathematical problems were her favorite hobbies; indeed, she liked mathematics so much that she was about to enroll herself as an architecture major but finally chose biotechnology. Ye moved from her hometown in the Northwest of China, Baoji—famous for housing the Zhou dynasty’s bronzeware and being close to the Terracotta Army—to Beijing for her college and graduate studies.Ye is proud of being among the earliest researchers working on Caenorhabditis elegans in her country; for her PhD studies, she joined the lab of Hong Zhang, who at that time has just established the first C. elegans lab in China at the National Institute of Biological Sciences in Beijing. Ye identified epg-2 as an adaptor for cargo recognition during autophagy. In 2010, she crossed the Pacific toward the U.S. West Coast for her postdoctoral training in the aging field with Andrew Dillin, first at the Salk Institute in San Diego and then at the University of California, Berkeley. There, she discovered that mild mitochondrial stress during development in worms rewires their chromatin landscape to establish specific gene expression patterns throughout the lifespan and promote longevity.Ye Tian. Photo courtesy of Ye Tian.Ye came back to China at the end of 2016 to start her own lab at the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences. Her research team studies mitochondrial stress signaling pathways and their interplay with aging. We chatted with her to learn more about her next scientific plans.What interested you about the interplay between mitochondria and aging?I became interested in mitochondrial biology during my postdoc in Andrew Dillin’s lab. Since the origin of eukaryotic cells, mitochondria have been a driving force of evolution. During reproduction, mitochondria are passed from the mother to the offspring through egg cells and they exhibit a unique inheritance pattern. As essential hubs that dictate cellular metabolism, it is clear now that mitochondria and the nucleus maintain a bidirectional communication. Early life “stressed” mitochondria communicate with the nucleus to induce gene expression changes that are beneficial on longevity and persist throughout the lifespan. The fact that mitochondrial function is crucial to aging fascinated me; I wanted to continue exploring that topic further, and that’s why I established my lab around the question of how mitochondrial surveillance mechanisms regulate the aging process.What are you currently working on? What is up next for you?My research team focuses on the interplay between mitochondrial stress signaling pathways and aging. The first work that my lab published was a project that I started during my postdoc. The Dillin lab reported a phenomenon in which perturbations of mitochondria in neurons induced a mitochondrial stress response in the peripheral tissues and hypothesized that a secreted signal molecule, named after mitokine, is required for the cell non-autonomous regulation (1). The identity of this molecular signal remained elusive for almost ten years until we found that a secreted Wnt ligand, EGL-20, functions as the mitokine to coordinate mitochondrial stress signaling across tissues and promote longevity of the organism (2). We are also interested in how the crosstalk between mitochondria and the nucleus influences lifespan. We found that mitochondrial perturbations alter the nuclear epigenome to induce longevity via the histone deacetylation complex NuRD in response to cellular acetyl-CoA levels, the key metabolite at the entry point of the Krebs cycle (3).Lab group picture; current lab members (2021). Photo courtesy of Ye Tian.Our latest work stemmed from a serendipitous observation that neuronal mitochondrial stress is sensed by and transmitted through the mitochondria in the germline. Intergenerational, maternal inheritance of elevated levels of mitochondrial DNA via the mitokine Wnt/EGL-20, which causes the activation of the mitochondrial unfolded protein response (UPR^mt), provides descendants with a greater tolerance to environmental stress. This makes the offspring live longer (4).Among our short-term scientific plans, we’re determining how mitochondria functions during the aging process at both the genetic and biochemical levels and searching for ways to apply our findings from C. elegans to neurodegenerative disease models in mammals.What kind of approach do you bring to your work?The curiosity about how things work drives me; what I enjoy the most is when I see things happening in front of my eyes and when I figure out why they occur that way. That enthusiasm is what I try to spread to my team every day. In the lab, we rely on C. elegans as our model system and on genetics to dissect complex biological processes like aging. We have also adapted modern biochemical and imaging techniques as well as bioinformatics to complement our genetic studies. I’m a geneticist at heart, and I like to initiate a project with a well-designed genetic screen. The best part is that the screen often leads me to answers I was not expecting, and that’s genuinely inspiring!What did you learn during your PhD and postdoc that helped prepare you for being a group leader? What were you unprepared for?Like most scientists, my research career has gone through ups and downs. I had to change my research project in the last year of my graduate school; that was nerve-racking, but I eventually managed to redirect my thesis and get exciting results under time pressure, thanks in large to the support of my parents, mentors, and lab mates. That helped me prepare to become a principal investigator; I gained confidence in problem solving, and since I’ve experienced the stress of dealing with last-minute scope changes firsthand, I connect better with my students.I guess, as many other non-native English speakers, I wasn’t prepared for writing grants and papers fluently in English. This issue wasn’t obvious during my graduate and postdoctoral studies, as my mentors were always there for me and proofread and edited my writing. Now I have to stand up for myself. I spend most of my time writing; I’ve improved my writing skills but it’s still an ongoing process.Reconstruction of the nerve system of C. elegans by confocal microscopy. Green corresponds to YFP-labeled neuronal specific marker Q40, and red labels germline specific mitochondrial outer membrane protein TOMM-20::mkate2. Image courtesy of Ye Tian’s lab.What has been the biggest accomplishment in your career so far?My very first PhD student, Qian Zhang, graduated with two first-author papers and decided to pursue a research career in academia. Being responsible for someone else’s career is challenging but also rewarding.What has been the biggest challenge in your career so far?I use the model organism C. elegans for my research in aging, so from time to time, peers criticize the relevance of my work to human health. I’m used to justifying my scientific approach to funding agencies and peers in other fields, but sometimes it’s exhausting or not pleasant.Who were your key influences early in your career?My PhD mentor, Hong Zhang. He is very passionate about the science he does, and he is courageous to shift his research directions to answer new biological questions.What is the best advice you have been given?I think the best advice I’ve gotten is that “tomorrow is another day.” It reminds me to keep going and be optimistic.What hobbies do you have?I love art and music. When I was in San Diego, I used to play in the Chinese Music Band; I miss my musician friends over there. In my teens, I used to hike mountainside trails along the river with my parents. Now, running has become my new favorite hobby. I enjoy the tranquility and peace of mind while running; it’s soothing.     

Advice to a young scientist (by someone who doesn’t know how to give it)

While trying to extract original and general advice from the details of my career, I realized this might not be possible. My path, like those of so many others, had too many idiosyncratic twists and turns that had to work out just the way they did to be mined for generally useful strategies. So I abandon the conceit of advice and simply give you my story. There are many like it, but this one is mine. Take what you wish from it.     

A Reminiscence

Leslie Orgel and Francis Crick with Gobind Khorana in Madison, Wisconsin (December 1965). I first met Leslie at the Endicott House (MIT) in February 1964. Leslie was then spending a period of time at MIT and the occasion was a party for him. During our conversation, Leslie talked about starting some experimental work. He seemed to be particularly interested in polyphosphates and the chemical activation of small molecules (building blocks).Shortly after his move to the Salk Institute in the Fall of 1964 I visited him in January 1965. He already had a lab going. I remember meeting Jim Ferris, in particular, and John Sulston sometime later. That particular time was exciting for my research as well. We had the first results on the Genetic Code using the chemical-biochemical approach that my lab had developed. Francis Crick was also at the Salk Institute during the time of my visit. Both Leslie and Francis were very excited by my results and they began to ask a lot of questions and gave me a whole lot of suggestions about further experiments. In fact, my thinking and planning of things that we were doing were so scrutinized and clarified during these discussions that, it seemed to me, my own group had only to turn out all the experiments that were needed. These interactions with Francis and Leslie continued intensively throughout that year and later. In fact, both Leslie and Francis accepted my invitation to Madison in December 1965 for more discussions.Since those early days of the Salk Institute, I have made numerous visits over the years to Leslie and his research group. It has always been very exciting to learn about the many discoveries bearing on chemical evolution that have unfolded from Leslie's research group. In addition, I have always benefitted from the insightful comments that Leslie invariably provided on my own research. I look forward to our continued interactions and friendship in the future.Leslie, A Happy Birthday!     

Borrowed robes

Should scientists indulge their fantasies by writing fiction? Subject Categories: Careers, Economics, Law & Politics, History & Philosophy of Science

Like a substantial fraction of the literate population, I have a collection of unpublished novels in the drawer. Six of them in fact. Some of them were composed in barely more than a week, and others I have been struggling to complete for over 10 years: so maybe it is more accurate to say five and a half. Anyhow, most of them are good to go, give or take a bit of editorial redlining. Or, as my helpful EMBO editor would say, the removal of thousands of unnecessary adverbs and dubiously positioned commas.What do I write about and why? My style is not unique but rather particular. I write fiction in the style of non‐fiction. My subject matter is somewhere in the general realms of science fiction, alternate history and political drama. Putting these ingredients together, and taking account of my purported day job as a serious scientist, it is easy to see why my fictional work is potentially subversive—which is one reason why I have been rather reluctant thus far to let it out of the drawer. At the very least, I should take pains to conceal my identity, lest it corrupts perceptions of my scientific work. Even if I regularly tell my students not to believe everything they read, it would impose far too great a burden on them if they came to question my peer‐reviewed articles purely on the basis of untrue statements published in my name, spoken by jaded politicians, washed‐up academics or over‐credulous journalists. Even if they are imaginary. Real journalists are theoretically bound by strict rules of conduct. But imaginary ones can do whatever they like.Today, I noticed a passage in one of these unpublished works that is clearly written in the style of a young William Shakespeare, dealing with a subject matter that fits neatly into one of his most famous plays. In fact, the illusion was such that I was sure I must have lifted the passage from the play in question and set about searching for the quote, which I then could and should cite. Yet, all Internet searches failed to find any match. The character in whose mouth I placed the words was depicted as being in a delirious state where the boundaries of fact and fiction in his life were already blurred; borrowed identities being one of the themes of the entire novel and arguably of my entire oeuvre. But am I guilty here of plagiarism or poetry, in adopting the borrowed identity of my national playwright?In another work, I lay great emphasis on the damaging role of mitochondrial reactive oxygen species (ROS) as the cause of biological ageing. I have even grafted this explanation onto a thinly disguised version of one of my most valued colleagues. Although there is some support for such a hypothesis from real science, including some papers that I have myself co‐authored, it is also a dangerously broad generalization that leads easily into wrong turnings and misconstructions—let alone questionable policies and diet advice. But, by advancing this misleading and overly simplistic idea in print, have I potentially damaged not only my own reputation, but that of other scientists whom I respect? Even if the author’s identity remains hidden.In one novel, I fantasize that nuclear weapons, whilst they do undoubtedly exist, have in fact been engineered by their inventors so as never actually to work, thus preventing their possible misuse by vainglorious or lunatic politicians unconcerned with the loss of millions of lives and planetary ruin. But if any insane national leader—of which there are unfortunately far too many—would actually come to believe that my fiction in the style of non‐fiction were true, they might indeed risk the outbreak of nuclear war by starting a conventional one in order to secure their strategic goals.Elsewhere, I vindicate one author of published claims that were manifestly based on falsified data, asserting him to have instead been the victim of a conspiracy launched to protect the family of an otherwise much respected American President. None of which is remotely true. Or at least there is no actual evidence supporting my ridiculous account.I have great fun writing fiction of this kind. It is both liberating and relaxing to be able to ignore facts and the results of real experiments and just invent or distort them to suit an imaginary scenario. In an age when the media and real politicians have no qualms about propagating equally outrageous “alternative facts”, I can at least plead innocent by pointing out that my lies are deliberate and labelled as such, even if people might choose to believe them.In a further twist, the blurb I have written to describe my latest work characterizes it as the “semi‐fictionalized” biography of a real person, who was, in fact, a distant relative of mine. But if it is semi‐fictionalized, which bits are true and which are made up? Maybe almost the whole thing is invented? Or maybe 99% of it is based on demonstrable facts? Maybe the subject himself concocted his own life story and somehow planted it in falsified documents and newspaper articles to give it an air of truth. Or maybe the assertion that the story is semi‐fictionalized is itself a fictional device, that is, a lie. Perhaps the central character never existed at all.It is true (sic) that the most powerful fiction is grounded in fact—if something is plausible, it is all the more demanding of our attention. And, it can point the way to truths that are not revealed by a simple catalogue of factual information, such as in a scientific report.But I have already said too much: if any of my novels ever do find their way into print, and should you chance to read them, I will be instantly unmasked. So maybe I’ll have to slot in something else in place of my pseudo‐Shakespearean verse, mitochondrial ROS hypothesis, defunct weapons of mass destruction and manipulated data manipulation.     

Arabidopsis calcium-binding mitochondrial carrier proteins as potential facilitators of mitochondrial ATP-import and plastid SAM-import

Chloroplasts and mitochondria are central to crucial cellular processes in plants and contribute to a whole range of metabolic pathways. The use of calcium ions as a secondary messenger in and around organelles is increasingly appreciated as an important mediator of plant cell signaling, enabling plants to develop or to acclimatize to changing environmental conditions. Here, we have studied the four calcium-dependent mitochondrial carriers that are encoded in the Arabidopsis genome. An unknown substrate carrier, which was previously found to localize to chloroplasts, is proposed to present a calcium-dependent S-adenosyl methionine carrier. For three predicted ATP/phosphate carriers, we present experimental evidence that they can function as mitochondrial ATP-importers.     

Halcyon days with Bill Arnold

The circumstances that led to the discovery that plants luminesce after they are illuminated are described, as are other discoveries that would not have been possible were it not for the fortuitous association I had with my dear and most admirable friend, W.A. Arnold, to whom this special issue is dedicated.     

Looking back on a life of unacknowledged privilege and a call to action

The year 2020 provided a wake-up call about the role systemic racism plays in shaping our nation and shaping science. While hard work and great mentors helped bring me a long way from a farm in Minnesota, it’s become much clearer that the privilege of being white and male and the accumulated advantages that began there played powerful roles. It’s time for white scientists like me to listen, think, and take action.

We all have personal stories that we use to describe our trajectory in life and science. For the past five decades the narrative I told myself was a simple one of good luck, hard work, support from my community, and mentors at pivotal times. However, in many important ways, this was just a small part of the truth, ignoring the role unperceived privilege played. The many underlying injustices that were laid bare in our nation this past year began to open my eyes, prompting me to look back at the roles hidden privilege played in my career and the power that these have given me. This challenged me to use the power of that privilege to speak and act to try to change the system in which engrained advantages benefit some but not all. I am telling my story in hopes it will encourage my white colleagues to examine their own.     

Astrocytes Provide Metabolic Support for Neuronal Synaptic Function in Response to Extracellular K<Superscript>+</Superscript>

It is an honour to have this opportunity write an article in recognition of the immense contributions of Bruce Ransom to the field of glial research. For me (BAM) personally there are many highlights both as a colleague and a friend that come to mind when I reflect on the many years that I have known Bruce. My own entry into the glial field was inspired by the early work by Ransom and his lab showing the sensitivity of astrocytes to neuronal activity. During my PhD and postdoctoral research I read these early papers and was inspired to ask the question when I first set up my independent lab in 1983: what if astrocytes also express some of the multitude of ion channels or transmitter receptors that were beginning to be described in neurons? Could they modify neuronal excitability during seizures or behaviour? As it turned out this was not only true but glial-neuronal interactions continues to be a growing and exciting field that I am still working in. I first met Bruce at the 1984 Society for Neuroscience meeting in Anaheim at my poster describing voltage gated calcium channels in astrocytes in cell culture. That was the start of a great friendship and years of discussions and collaborations. This review describes recent work from my lab led by Hyun Beom Choi that followed and was inspired by the groundbreaking studies by Bruce on electrophysiological and pH recordings from astrocytes and on glycogen mobilization in astrocytes to protect white matter axons.     

Differential gel electrophoresis and transgenic mitochondrial calcium reporters demonstrate spatiotemporal filtering in calcium control of mitochondria

Mitochondria must adjust both their intracellular location and their metabolism in order to balance their output to the needs of the cell. Here we show by the proteomic technique of time series difference gel electrophoresis that a major result of neuroendocrine stimulation of the Drosophila renal tubule is an extensive remodeling of the mitochondrial matrix. By generating Drosophila that were transgenic for both luminescent and fluorescent mitochondrial calcium reporters, it was shown that mitochondrial calcium tracked the slow (minutes) but not the rapid (<1 s) changes in cytoplasmic calcium and that this resulted in both increased mitochondrial membrane polarization and elevated cellular ATP levels. The selective V-ATPase inhibitor, bafilomycin, further enhanced ATP levels, suggesting that the apical plasma membrane V-ATPase is a major consumer of ATP. Both the mitochondrial calcium signal and the increase in ATP were abolished by the mitochondrial calcium uniporter blocker Ru360. By using both mitochondrial calcium imaging and the potential sensing dye JC-1, the apical mitochondria of principal cells were found to be selectively responsive to neuropeptide signaling. As the ultimate target is the V-ATPase in the apical plasma membrane, this selective activation of mitochondria is clearly adaptive. The results highlight the dynamic nature and both spatial and temporal heterogeneity of calcium signaling possible in differentiated, organotypic cells and provide a new model for neuroendocrine control of V-ATPase.     

An unconventional route to becoming a cell biologist

I am honored to be the E. B. Wilson Award recipient for 2015. As we know, it was E. B. Wilson who popularized the concept of a “stem cell” in his book The Cell in Development and Inheritance (1896, London: Macmillan & Co.). Given that stem cell research is my field and that E. B. Wilson is so revered within the cell biology community, I am a bit humbled by how long it took me to truly grasp his vision and imaginative thinking. I appreciate it deeply now, and on this meaningful occasion, I will sketch my rather circuitous road to cell biology.I grew up in a suburb of Chicago. My father was a geochemist, and for everyone whose parents worked at Argonne National Laboratories, Downers Grove was the place to live. My father’s sister was a radiobiologist and my uncle was a nuclear chemist, both at Argonne; they lived in the house next door. Across the street from their house was the Schmidtke’s Popcorn Farm—a great door to knock on at Halloween. The cornfields were also super for playing hide-and-seek, particularly when you happened to be shorter than those Illinois cornstalks.Open in a separate windowElaine FuchsI remember when the first road in the area was paved. It made biking and roller-skating an absolute delight. Fields of butterflies were everywhere, and with development came swamps and ponds filled with pollywogs and local creeks with crayfish. It was natural to become a biologist. When coupled with a family of scientists and a mother active in the Girl Scouts, all the resources were there to make it a perfect path to becoming a scientist.I could hardly wait until I was in junior high school, when I could enter science fairs. You would think that my science-minded family might help me choose and develop a research project. True to their mentoring ethos, they left these decisions to me. My first project was on crayfish behavior. I recorded the response of the crayfish I had caught to “various external stimuli.” At the end of this assault, I dissected the crayfish and, using “comparative anatomy,” attempted to identify all the parts. The second project was no gentler. I focused on tadpole metamorphosis and the effects of thyroid hormone in accelerating development at low concentrations and death at elevated concentrations. Somehow, I ended up going all the way to the state fair, where it became clear that I had serious competition. That experience, however, whetted my appetite to gain more lab experience and to learn to read the literature more carefully.My experience with high school biology prompted me to gravitate toward chemistry, physics, and math. When it came to college, my father told me that if there was a $2000/year (translated in 2015 to be $30,000/year) reason why I should go anywhere besides the University of Chicago (where Argonne scientists received a 50% tuition cut for their children) or the University of Illinois (then $200/year tuition), we could “discuss” it further. Having a sister, father, aunt, and uncle who went to the University of Chicago, I chose the University of Illinois and saved my Dad a bundle of money. At Illinois, I thought I might revisit biology, but my choices for a major were “biology for teachers” or “honors biology.” The first did not interest me; the second seemed intimidating.I enrolled as a chemistry major. Four years went by, during which time I never took a biology class. I enjoyed quantum mechanics, physics, and differential equations, and problem solving became one of my strengths. In the midst of the Vietnam War era, however, Illinois was a hotbed of activity. I was inspired to apply to the Peace Corps, with a backup plan to pursue science that would be more biomedically relevant than quantum mechanics. I was accepted to go to Uganda with the Peace Corps, but with Idi Amin in office, my path to science was clear. Fortunately, the schools I applied to accepted me, even though, in lieu of GRE scores, I had submitted a three-page essay on why I did not think another exam was going to prove anything. I chose Princeton’s biochemistry program. This turned out to be a great, if naïve choice, as only after accepting their offer did I take a biochemistry class to find out what I was getting into. I chose to carry out my PhD with a terrific teacher of intermediary metabolism, Charles Gilvarg, who worked on bacterial cell walls. My thesis project was to tackle how spores break down one cell wall and build another as they transition from quiescence to vegetative growth.By my fourth year of graduate school, I was trained as a chemist and biochemist and was becoming increasingly hooked on biomedical science. I listened to a seminar given by Howard Green, who had developed a method to culture cells from healthy human skin under conditions in which they could be maintained and propagated for hundreds of generations without losing their ability to make tissue. At the time, Howard referred to them as epidermal keratinocytes, but in retrospect, these were the first stem cells ever to be successfully cultured. I was profoundly taken by the system, and Howard’s strength in cell biology inspired me. It was the perfect match for pursuing my postdoctoral research. The time happened to be at the cusp of DNA recombinant technology.At MIT, I learned how to culture these cells. I wanted to determine their program of gene expression and how this changed when epidermal progenitors embark on their terminal differentiation program. While the problem in essence was not so different from that of my graduate work at Princeton, I had miraculously managed to receive my PhD without ever having isolated protein, RNA, or DNA. Working in a quintessential cell biology lab and tackling a molecular biology question necessitated venturing outside the confines of the Green lab and beyond the boundaries of my expertise. Fortunately, this was easy at MIT. Richard Hynes, Bob Horvitz, Bob Weinberg, and Graham Walker were all assistant professors, and their labs were very helpful, as were those of David Baltimore and Phil Sharp, a mere walk across the street. On the floor of my building, Steve Farmer, Avri Ben Ze’ev, Gideon Dreyfuss, and Ihor Lemischka were in Sheldon Penman’s lab just down the hall, and they were equally interested in mRNA biology, providing daily fuel for discussions. Uttam Rhajbandary’s and Gobind Khorana’s labs were also on the same floor, making it easy to learn how to make oligo(dT)-Sepharose to purify my mRNAs. Vernon Ingram’s lab was also on the same floor, so learning to make rabbit reticulocyte lysates to translate my mRNAs was also possible. Howard bought a cryostat, so I could section human skin and separate the layers. And as he was already working with clinicians at Harvard to apply his ability to create sheets of epidermal cells for the treatment of burn patients, I had access to the leftover scraps of human tissue that were also being used in these operations.The three years of my postdoc were accompanied by three Fuchs and Green papers. The first showed that epidermal keratinocytes spend most of their time expressing a group of keratin proteins with distinct sequences. The second showed that these keratins were each encoded by distinct mRNAs. The third showed that, as epidermal keratinocytes commit to terminally differentiate, they switch off expression of basal keratins (K5 and K14) and switch on the expression of suprabasal keratins (K1 and K10). That paper also revealed that different stratified tissues express the same basal keratins but distinct sets of suprabasal keratins. I am still very proud of these accomplishments, and my MIT experience made me thirst to discover more about the epidermis and its stem cells.My first and only real job interview came during my second year of postdoc, at a time when I was not looking for a job. I viewed the opportunity, initiated by my graduate advisor, as a free trip home to visit my parents and my trial run to prepare me for future searching. I was thrilled when this interview materialized into an offer to join the faculty, for which the University of Chicago extended my start time to allow me to complete my three years with Howard.Times have clearly changed, and it is painful to see talented young scientists struggle so much more today. That said, I have never looked ahead very far, and having a lack of expectations or worry is likely to be as helpful today as it was then. I am sure it is easier said than done, but this has also been the same for my science. I have always enjoyed the experiments and the joy of discovery. There was no means to an end other than to contemplate what the data meant in a broader scope.I arrived at the University of Chicago with a well-charted route. My aim was to make a cDNA library and clone and characterize the sequences and genes for the differentially expressed keratins I had identified when I was at MIT. It was three months into my being at Chicago when my chair lined up some interviews for me to hire a technician. I was so immersed in my science that I did not want to take time to hire anyone. I hired the first technician I interviewed. Fortunately, it worked out. However, I turned graduate students away the first year, preferring to carry out the experiments with my technician and get results. After publishing two more papers—one on the existence of two types of keratins that were differentially expressed as pairs and the other on signals that impacted the differential expression of these keratin pairs, I decided to accept a student, who analyzed the human keratin genes. My first postdoc was a fellow grad student with me at Princeton; she studied signaling and keratin gene expression. My second postdoc was initiated by my father, who chatted with him at the elevator when I was moving into my apartment. He set up DNA sequencing and secondary-structure prediction methods, and the lab stayed small, focused, and productive.I was fascinated by keratins, how they assembled into a network of intermediate filaments (Ifs). When thalassemias and sickle cell anemia turned out to be due to defects in globin genes, I began to wonder whether there might be human skin disorders with defective keratin genes. I had no formal training in genetics, and there were no hints of what diseases to focus on. Thus, rather than using positional cloning to identify a gene mutation associated with a particular disease, we took a reverse approach: we first identified the key residues for keratin filament assembly. After discovering that mutations at these sites acted dominant negatively, we engineered transgenic mice harboring our mutant keratin genes and then diagnosed the mouse pathology. Our diagnoses, first for our K14 mutations and then for our K10 mutations, turned out to be correct: on sequencing the keratins from humans with epidermolysis bullosa simplex (EBS), we found K14 or K5 mutations; similarly, we found K1 or K10 mutations in affected, but not in unaffected, members of families with epidermolytic hyperkeratosis (EH). Both are autosomal-dominant disorders in which patients have skin blistering or degeneration upon mechanical stress. Without a proper keratin network, the basal (EBS) or suprabasal (EH) cells could not withstand pressure. Ironically, family sizes of all but the mildest forms of these disorders were small, meaning that the disorders were not amenable to positional cloning. But the beauty of this approach is that once we had made the connection to the diseases, we understood their underlying biology. In addition, the IF genes are a superfamily of more than 100 genes differentially expressed in nearly all tissues of the body. Once we had established EBS as the first IF gene disorder, the pathology and biology set a paradigm for a number of diseases of other tissues that turned out to be due to defects in other IF genes.Fortunately, I had students, Bob Vassar (professor, Northwestern University) and Tony Letai (associate professor, Harvard Medical School), and a postdoc, Pierre Coulombe (chair, Biochemistry and Molecular Biology, Johns Hopkins University), who jumped into this fearless venture with me. We had to go off campus to learn transgenic technology. I had never worked with mice before. When Bob returned to campus with transgenic expertise, we hired and trained Linda Degenstein, whose love for animal science was unparalleled. Pierre’s prior training in electron microscopy was instrumental in multiple ways. Additionally, I was not a dermatologist and had no access to human patients. Fortunately Amy Paller, MD, at Northwestern volunteered to work with us.The success of this project attests to an important recipe: 1) Pursue a question you are passionate about. 2) In carrying out rigorous, well-controlled experiments, each new finding should build upon the previous ones. 3) If you have learned to be comfortable with being uncomfortable, then you will not be afraid to chart new territory when the questions you are excited to answer take an unanticipated turn. 4) Science does not operate in a vacuum. Interact well with your lab mates and take an interest in their science as well as your own. And wherever you embark upon a pathway in which the lab’s expertise is limited, do not hesitate to reach out broadly to other labs and universities.I have followed this recipe now for more than three decades, and it seems to work pretty well. A lab works only when its students and postdocs are interactive, naturally inquisitive, and freely share their ideas and findings. I have been blessed to have a number of such individuals in my lab over the years. When push comes to shove, I am always inclined first to shave from the “brilliant” category and settle for smart, nice people who are passionate and interactive about science and original and unconventional in their thinking.So what questions have I been most passionate about? I have always been fascinated with how tissues form during development, how they are maintained in the adult, and how tissue biology goes awry in human disorders, particularly cancers. I first began to think about this problem during my days at Princeton. I also developed a dogma back then that I still hold: to understand malignancies, one must understand what is normal before one can appreciate what is abnormal. I think this is why I have spent so much of my life focusing on normal tissue morphogenesis, despite my passion for being at the interface with medicine. And because skin has so many amazingly interesting complexities, and because it is a great system to transition seamlessly between a culture dish and an animal, I have never found a reason to choose any other tissue over the one I chose many years back.I will not dwell on the various facets of skin biology we have tackled over the years. Our initial work on keratins was to obtain markers for progenitors and their differentiating lineages. This interest broadened to understanding how proliferative progenitors form cytoskeletal networks and how the cytoskeleton makes dynamic rearrangements during tissue morphogenesis.From the beginning, the lab has also been fascinated by how tissue remodeling occurs in response to environmental signals. Indeed, signals from the microenvironment trigger changes in chromatin dynamics and gene expression within tissue stem cells. Ultimately, this leads to changes in proteins and factors that impact on cell polarity, spindle orientation, asymmetric versus symmetric fate specifications, and ultimately, the balance between proliferation and differentiation.The overarching theme of my lab over these decades is clear, namely, to understand the signals that unspecified progenitors receive that instruct them to generate a stratified epidermis, make hair follicles, or make sweat and sebaceous glands. And if we can understand how this happens, then how are stem cells born, and how do they replace dying cells or regenerate tissue after injury? And, finally, how does this process change during malignant progression or in other aberrant skin conditions?In tackling tissue morphogenesis, I have had to forgo knowing the details of each tree and instead focus on the forest. There are many times when I stand back and can only admire those who are able to dissect beautiful cellular mechanisms with remarkable precision. But I crossed that bridge some years ago in tackling a problem that mandates an appreciation of nearly all the topics covered in Bruce Alberts’ textbook Molecular Biology of the Cell. I am now settled comfortably with the uncomfortable, and the problem of tissue morphogenesis in normal biology and disease continues to keep me more excited about each year’s research than I was the previous year. Perhaps the difference between my days as a student, postdoc, and assistant professor and now is that my joy and excitement is as strong for those I mentor and have mentored as it is for myself.     

The story of science: successes,failures, luck,privilege, and bias

I am incredibly honored to receive the 2021 WICB Junior Award for Excellence in Research in WICB’s golden jubilee year. In this essay, I traverse my scientific journey starting with my PhD, highlighting the highs and the lows and how these intersect with luck, privilege, and bias.

V. AnanthanarayananMy pursuit for a PhD started with a hiccup—I had applied to several places in the United States, but barely got any offers due to the economic upheaval that happened that year (2008). I had to forgo any dreams of a PhD in the United States and remained in Bangalore, India to complete a project I had started with William (Bill) Thies at Microsoft Research India on a programming language for expressing biology protocols. Applying to U.S. schools was an expensive task, one which I was unwilling to put my family through again. So, a year later, when I recommenced my search for a PhD position, I set my sights on Europe. I had heard about the PhD program at the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG ) at Dresden from a friend who had just joined the institute for her PhD. Fortunately, I received an interview call from MPI-CBG. At the end of a crucial interview week at Dresden, I “matched” with Iva Tolic´’s (now Institut Ruđer Boškovic´, Croatia) lab for my PhD. At the start of my PhD, I knew next to nothing about the cytoskeleton, motor proteins, or microscopy, but I found Iva and my lab members to be some of the warmest and most welcoming people. I made friends for life and graduated with a PhD in Biophysics, with a thesis focused on understanding the regulation of the motor protein cytoplasmic dynein. I was lucky to have been able to get a position at MPI-CBG and join Iva’s lab—of the other three places in Europe I had applied to for a PhD, only one other institute invited me for an interview, which also proved to be unsuccessful.On completing my PhD in 2014, I didn’t quite know what I wanted to do. Due to personal reasons, I had to return to India and was open to options in both industry and academia. But with my training in motor protein and cytoskeleton research, I had some ideas for exploring scientific questions related to dynein activation. However, most labs I approached for a postdoctoral position were not open to a project that was outside the realm of their research focus. Nonetheless, Iva, Nenad Pavin (University of Zagreb), and Jonathon (Joe) Howard (Yale University), who were members of my thesis advisory committee, gave me the courage to continue in academia. In my naïveté, I went ahead and applied for the INSPIRE Faculty Fellowship, which is targeted at fresh PhDs and junior postdoctoral fellows to establish their own independent group at an Indian institute. To my surprise, I ended up getting the fellowship. The next issue was finding a host institute that was preferably in Bangalore, where my partner was based. I applied at a few different places, but only after I attended IndiaBioscience’s Young Investigator Meeting in 2014 did I get the chance to meet representatives of potential host institutes, including the Indian Institute of Science (IISc). After a couple of research seminars at IISc, my application was assessed and I was offered the position of INSPIRE Faculty Fellow at the newly formed Centre for BioSystems Science and Engineering, IISc.While I did not have any additional start-up funding, I was given the infrastructure and the independence to pursue my research program. It was slow and frustrating at the start, not unlike most starting labs. I always wondered if it might have been easier if I had had a regular postdoctoral stint. During this time, I also started recognizing how hard it was to be a woman in Indian academia. As a woman principal investigator, one’s authority, expertise, and ability are constantly called into question. Justifying your presence in academia on a daily basis is an exhausting task. I had a great mentor in Sandhya Visweswariah (IISc) who helped me navigate the system. I also had an extremely supportive partner, who kept me going through some of the worst times. Eventually, my lab and I landed on our feet (more about this in “My INSPIRE’d Journey”). Our research has been recognized with grants and awards, but one of the most rewarding parts of the job is seeing other lab members discovering the joy of science (I wrote about my approach to mentorship recently [https://www.nature.com/articles/s41580-020-0256-6]).Three years into the faculty fellowship, I was able to transition to an Assistant Professor position in the same institute. However, this did not change my experience as a young woman in Indian science, and the implicit and explicit biases continued. In 2020, I accepted a fantastic opportunity to further my lab’s science as an EMBL Australia Group Leader at the Single Molecule Science Node at UNSW Sydney and made the move during a pandemic. My lab’s research focus is in understanding how stochastic and rare events pertaining to cytoskeleton and motor proteins give rise to complexity in intracellular organization. With this theme as the essence of our research, we ask specific questions about motor protein regulation to effect differential cellular trafficking, mitochondria-microtubule interactions, and their role in mitochondrial dynamics, and we aim to determine barcodes of global organelle positioning in health and disease.I have the privilege of being able-bodied, born in an upper middle-class family to college-educated parents who were extremely supportive of my choices. I have also inordinately benefitted from the fact that I was born to an Indian ‘upper caste’ family. I therefore had an undue head start in life. These were circumstances beyond my control and yet played a huge role in how my story turned out. I was embarrassingly ignorant of the rampant misogyny in academia until I had to contend with explicit and implicit gender-based biases myself when I started my independent research group in India. Women make up ∼40% of science PhDs awarded in India but represent only ∼13% of Indian academia (biaswatchindia.com), highlighting the stark gender biases at play in creating a leaky pipeline. While I tried my best to voice my discontent and affect changes to create an equitable environment within my department and institute, it was slow work. In 2020, when the pandemic hit and all conferences and meetings went virtual, conference posters advertised on social media made it immediately apparent just how much women were underrepresented in Indian STEM conferences. So, I teamed up with Shruti Muralidhar (now a scientist at Deep Genomics, Canada) to found BiasWatchIndia, an initiative to document women representation and combat gender-biased panels in Indian STEM conferences.BiasWatchIndia has been in existence for a little over a year now—we have achieved several milestones, but there’s still so much to do. “Manels” (conferences that feature only men) are still as rampant as they were when we first started—40% of all Indian STEM conferences are manels. And while we have just about started to tackle the underrepresentation of women in Indian STEM, we are conscious of the intersectionality of bias with gender, caste, ableism, and socioeconomic background and aim to understand how best we can advocate for all minorities.People who are in power in academia and who oppose equity, diversity, and inclusion initiatives and instead preach merit and equality as the gold standard need to introspect, because when options and opportunities are offered without consideration to the millennia of oppression based on gender, race, and background, it is not promoting equality but upholding values that will continue to oppress underrepresented groups. Still, I am optimistic and hope to see real changes that will result in equity in academia in my lifetime.     

You are the most valuable reagent in the lab: mental health before and during the pandemic

No one maps out their tenure as a postdoc anticipating a life-altering tragedy. But mental health crises of all kinds affect academic trainees and staff at similar or higher levels than the general public. While the mental health resources available to trainees are often set by healthcare providers, all levels of university leadership can work to remove material and immaterial obstacles that render such resources out of reach. I describe how access to care via telemedicine helped me following a loss in my family.

Over the years, my siblings and close friends have sought mental health resources like therapy, psychoanalysis, or psychiatry, so I loosely understood their benefits. When I was a PhD student I went to therapy briefly, but my counselor and I decided I could do without it. Since I started my postdoc, stress manifested in some new ways but I managed it well with my usual coping strategies and support. That changed one bright December morning in 2019 while I was preparing for our weekly lab meeting. My phone rang indicating a call from my father, whom I had spoken to the night before to celebrate the news of my nephew’s birth. But the voice on the phone was that of a family friend, telling me that my father had died overnight of an undiagnosed heart condition. In the moment I couldn’t even understand what was happening, saying over and over, “but I talked to him last night.” Soon I was sitting at home, dazed, on a string of tearful calls with family and friends.I often read words like “lifted” or “buoyed” to describe the stabilizing support of a network of loved ones. In my case this network was tethering me to reality over the next few weeks, preventing me from spinning off the Earth’s surface in a storm of sorrow and anxiety. The trauma also took a strange physical form and convinced me that I was suffering from a cardiac condition of my own. I had a panic attack during which I went to urgent care convinced my own heart was about to give way. Night after night these physical symptoms prevented me from sleeping.Graced by many loving connections with my siblings, my boyfriend, and close friends, I was actually weathering the process as well as one can. My PI gave me a firm directive to take as much time off as I needed. These were two key elements early in my healing process: a supportive network and an understanding advisor. The third was getting professional help, which I soon realized I needed. Even if I felt OK one day, I didn’t trust that I’d be OK the next. My grief formed too thick and too broad a landscape for me to navigate without help.Deciding to seek mental health resources and realizing that one needs them are often the hardest parts. Connecting with those resources once the decision has been made should be as simple as possible. I called a mental health number, and a triage counselor noted my therapy needs and verified my insurance. She asked what times and locations I preferred and then searched for an open appointment with a therapist who accepted my insurance. She also informed me that my coverage allowed 12 sessions with no copay, which was a pleasant surprise. The therapist who agreed to see me had very few openings, in part because this all happened in December—the holidays are especially busy for therapists. I was aiming for a time after normal working hours, or in the morning before I would head to lab, but none of those times were available. I didn’t like interrupting my workday to trot off to therapy. Taking a long break once a week meant I couldn’t run experiments or mentor my student during that time. But I made the sacrifice because my highest priority was getting the help I needed. There was no shortcut. Prioritizing mental health over lab work is tough for researchers, and I would never have accepted that kind of weekly disruption before my dad’s passing. But as a wonderful mentor of mine used to say, “You are the most valuable reagent in the lab.” She wasn’t describing mental health at the time, but the phrase now provided a guiding principle for my recovery. My first few sessions were on Tuesdays at 2:00 pm.The afternoon break turned out to be less disruptive than I had feared, because I had recently come back to the lab and was working short days. Had she asked, I would have told my PI where I was on Tuesday afternoons, but she wasn’t normally abreast of my daily schedule, so I didn’t seek her approval beforehand. Coordinating experiments with lab members thankfully wasn’t an issue because my work was largely independent; I simply let lab members know that I’d would be out of the lab for a bit on those days.The weeks went by, and the benefits of therapy accrued, helping me in large and small ways as I grieved. In mid-March of 2020, my therapist followed public health guidelines and asked all her clients to transition to remote sessions. While this was easy and sensible, it was still a little disappointing. Therapists are professional empaths, among many other things, and doing away with the physical presence and exchange with her was a blow. Yet therapy via video felt less odd simply because most of my social interactions were now virtual. Thankfully I didn’t have to move out of state for the lockdown (as did many students living in campus housing), which meant I could stay with the same therapist without any insurance complications.A few weeks into lockdown, I asked my therapist whether we had reached the limit of my 12 sessions without a copay. She replied with the good news that my insurance provider had waived all copays for mental health costs due to the pandemic. By that time therapy had generated a platform and an outlet to explore areas of my grief beyond the trauma of my father’s passing. Without needing to weigh the costs and benefits of this resource, I saw my therapist for another 4 months. I slowly took stock of my upbringing in an unconventional family and the loss of my mother when I was 25 and waded through a series of difficult decisions regarding my father’s estate. My father’s death changed me at a depth that is untouched by any amount of therapy or treatment. I’m not “healed”: I feel aged, more brittle, and a little ground down compared with who I had been. But therapy guided me through the worst of my grief, past the acute trauma to help me grasp what I was going through.Since the pandemic began, the number of people reporting increased stress or mental health issues has steadily increased (information on the impact of COVID-19 measures on mental health: https://www.apa.org/workforce/publications/depression-anxiety-coronavirus.pdf) (also see Mental health resources for trainees). I am fortunate to have affordable health insurance and the support from my lab and my department. The ease of finding my institution’s phone number for mental health resources was itself an important benefit. I share these pieces of my story with humility and understanding that not everyone enjoys the privileges that I do and the knowledge that everyone weathers life’s tragedies in their own way. It is not lost on me that some benefits stemmed from a policy change made by a private insurance provider. The provider made the right decision to waive copays, freeing me from having to choose between cost and my mental health needs. Yet had I been a student who had to move out of state due to COVID-19, access to mental health resources might have been disrupted or cut off. The need for reduced out-of-pocket costs for healthcare is known and needs no repetition, but the benefits of telehealth should be a low-cost component of health plans offered to students and staff (information on telehealth recommendations: https://www.apaservices.org/advocacy/news/congress-patient-telehealth?_ga=2.231013471.1538013741.1619359426-1228006513.1619359425 and http://www.apaservices.org/practice/advocacy/state/leadership/telebehavioral-health-policies.pdf?_ga=2.3385904.1067518037.1620039082-1228006513.1619359425.I’m not a cloud of emotions attached to a pair of good pipetting hands, I’m a human who is choosing to spend my time doing research. This observation is easy to repeat, by trainees as much as by faculty and administrators, but much harder to act upon in the midst of conflicting priorities. Consider my story a success: Because I could access the resources I needed, I was able to prioritize my mental health in the midst of my ambitious research program even during the lockdown.MEET THE AUTHORI have been a postdoc in Stefani Spranger’s lab at MIT for 4 years. Supported by an Irvington Fellowship from the Cancer Research Institute, my work examines the behaviors of dendritic cells in tumors that contribute to productive or unproductive anti-tumor immune responses. My doctoral work examined modes of multicellular invasion controlled by the actin cytoskeleton with Margaret Gardel at the University of Chicago. Earlier I was a lab technician with Thea Tlsty at the University of California, San Francisco, which followed a bachelor’s degree in biology at the University of California, Santa Cruz. I serve on the Committee for Students and Postdocs at the American Society for Cell Biology, where I chair the Outreach Subcommittee.     

The redox language in neurodegenerative diseases: oxidative post-translational modifications by hydrogen peroxide

Neurodegenerative diseases, a subset of age-driven diseases, have been known to exhibit increased oxidative stress. The resultant increase in reactive oxygen species (ROS) has long been viewed as a detrimental byproduct of many cellular processes. Despite this, therapeutic approaches using antioxidants were deemed unsuccessful in circumventing neurodegenerative diseases. In recent times, it is widely accepted that these toxic by-products could act as secondary messengers, such as hydrogen peroxide (H₂O₂), to drive important signaling pathways. Notably, mitochondria are considered one of the major producers of ROS, especially in the production of mitochondrial H₂O₂. As a secondary messenger, cellular H₂O₂ can initiate redox signaling through oxidative post-translational modifications (oxPTMs) on the thiol group of the amino acid cysteine. With the current consensus that cellular ROS could drive important biological signaling pathways through redox signaling, researchers have started to investigate the role of cellular ROS in the pathogenesis of neurodegenerative diseases. Moreover, mitochondrial dysfunction has been linked to various neurodegenerative diseases, and recent studies have started to focus on the implications of mitochondrial ROS from dysfunctional mitochondria on the dysregulation of redox signaling. Henceforth, in this review, we will focus our attention on the redox signaling of mitochondrial ROS, particularly on mitochondrial H₂O₂, and its potential implications with neurodegenerative diseases.Subject terms: Post-translational modifications, Neurodegenerative diseases     

Mutational analysis of antigen receptor regulation of B lymphocyte growth. Evidence for involvement of the phosphoinositide signaling pathway.

Stimulation of the antigen receptor of WEHI-231 B lymphoma cells with anti-receptor antibodies (anti-IgM) induces irreversible growth arrest. Anti-IgM stimulates two kinds of transmembrane signaling events, phosphorylation of proteins on tyrosyl residues and breakdown of inositol phospholipids, which results in increases of inositol phosphates, diacylglycerol, and calcium. The roles of these reactions in mediating the growth arrest of the B lymphoma cells have not been established. To examine this issue, we took a genetic approach. Mutants of WEHI-231 cells were isolated that were resistant to anti-IgM-induced growth arrest. Five out of seven independent mutants analyzed had normal cell-surface expression of antigen receptors. Although each of these five mutants had tyrosine protein phosphorylation patterns comparable to wild-type cells, they exhibited alterations in the phosphoinositide signaling pathway. Four of the mutants had decreased phosphoinositide breakdown, probably due to an alteration in phospholipase C. Decreased second messenger production may be responsible for the growth-resistant phenotype. Full growth arrest was restored upon addition of the calcium ionophore ionomycin, suggesting that the limiting second messenger was intracellular free calcium. The final mutant appeared to be altered in a component(s) that responds to diacylglycerol and calcium. Taken together, these results provide further evidence that the phosphoinositide pathway is at least partly responsible for mediating antigen receptor regulation of B lymphoma cell growth.     

Mitochondrial c-Jun N-terminal kinase (JNK) signaling initiates physiological changes resulting in amplification of reactive oxygen species generation

The JNK signaling cascade is critical for cellular responses to a variety of environmental and cellular stimuli. Although gene expression aspects of JNK signal transduction are well studied, there are minimal data on the physiological impact of JNK signaling. To bridge this gap, we investigated how JNK impacted physiology in HeLa cells. We observed that inhibition of JNK activity and JNK silencing with siRNA reduced the level of reactive oxygen species (ROS) generated during anisomycin-induced stress in HeLa cells. Silencing p38 had no significant impact on ROS generation under anisomycin stress. Moreover, JNK signaling mediated amplification of ROS production during stress. Mitochondrial superoxide production was shown to be the source of JNK-induced ROS amplification, as an NADPH oxidase inhibitor demonstrated little impact on JNK-mediated ROS generation. Using mitochondrial isolation from JNK null fibroblasts and targeting the mitochondrial scaffold of JNK, Sab, we demonstrated that mitochondrial JNK signaling was responsible for mitochondrial superoxide amplification. These results suggest that cellular stress altered mitochondria, causing JNK to translocate to the mitochondria and amplify up to 80% of the ROS generated largely by Complex I. This work demonstrates that a sequence of events exist for JNK mitochondrial signaling whereby ROS activates JNK, thereby affecting mitochondrial physiology, which can have effects on cell survival and death.     

University campuses need people in them

As COVID‐19 has turned universities into ghost towns, David Smith cannot wait for the day when his campus fills with life again.

In the novel Fool’s Fate, Robin Hobb writes: “Home is people. Not a place. If you go back there after the people are gone, then all you can see is what is not there anymore.” I feel the same about university campuses.In late August 2020, after months of working from home, I returned to the campus of Western University where I am an associate professor of biology. It was supposed to be a short visit, in and out to grab some notebooks and an external monitor. But when I unlocked the office door and sat in that old wooden desk chair amongst the calm clutter of my workspace, I did not get up for a good two hours. I was comforted by the familiarity of my bookshelves, photographs, and professorial memorabilia, including a large bust of Darwin and a giant whale’s tooth. How I missed this place. And apart from two dead plants and a generous layer of dust, everything was as it should be.Outside my office was a different story. The water fountains were covered up with caution tape. Bright purple floor markings indicated the correct side of the hallway to walk down. Main offices, libraries, and canteens were closed. Large signs on all major doorways reiterated the social distancing policies. And apart from the odd security officer or grounds person, the campus was eerily empty. Nevertheless, I decided that for as long as the university remained open, I would keep coming to my office for a few hours a day, mainly to read and write without the cacophonic company of a toddler, but also to bring back some semblance of normalcy to my work life.The plan started off well. Each morning I would pack a large lunch, walk to campus and enjoy a few uninterrupted hours of academic productivity. But the stillness and emptiness of the university began to weigh on me. I could swear the fluorescent lights in my office were buzzing more loudly than before. Was the central air system always this rickety? After an hour of writing, I would take a quick walk around the department to clear my mind and see if anyone else was in. On my fifth day, I finally found someone: Vera’s office door was propped open! I quickly checked that my mask was on correctly and poked my head around. Small talk—glorious small talk—ensued for at least fifteen minutes. I had forgotten how nice it was to chat with a colleague in person. I went back to my office refreshed and put in another hour of good work. The next day, the building was deserted again. Not a sliver of light beneath Vera’s or any other door.I hoped that maybe once classes resumed in mid‐September, some vitality would return to campus. But, of course, nearly all of the classes were online and students and staff stayed home. Sometimes on my departmental wanderings, I would go into one of the large lecture halls and just stand at the podium. Once I even plugged my laptop into the AV system and practiced a presentation that I was preparing for an upcoming Zoom talk. As strange as it sounds, speaking to hundreds of lifeless seats in that old, stuffy hall felt more natural than talking to a grid of black boxes with nametags on my computer screen.As the weeks wore on and my visits to campus continued, a deep melancholy slowly took hold of me. I would spend hours on seemingly simple tasks, like tidying my office or answering emails. Harder tasks, such as writing a paper or developing a new lecture, felt insurmountable. I started leaving everything to the last minute or missing deadlines completely, which is unlike me. It felt as if my mood was somehow mirroring that of the vacant classrooms and buildings surrounding me. They, too, were paying the price of the pandemic.I have spent most of my life on college campuses. My father was a chemistry professor and often took me to work with him when I was a small child. My first daycare was at a university. As an adolescent and teenager, I would go to the local college most days for after‐school clubs. I learnt to swim at a university pool, became a senior boys 1500 m running champion on a university track, and discovered my love of mountain biking and cross‐country skiing on university trails. I met my closest friends in university residences. And my passion for science and writing was fostered in university classrooms. I love universities. I love what they represent: places of learning, scholarship, and development. I love the palpable emotions that they emit, from the endless possibilities of the first week of classes to the anxieties and sense of completion during final examinations. Most of all, I love the people that make up universities, their eclectic mix of personalities, backgrounds, ages, and beliefs. This might sound strange, but when I go on vacation, I visit universities elsewhere. I will spend an entire afternoon roaming around a campus, reading in the library, or sitting on a bench watching people come and go. This may be why I am so sad that my current institute sits unoccupied, at least in the physical sense. Ironically, enrollment is up. My department has more new undergraduate students than it has had in years.The other day on my walk home from work I ran into a colleague. He described to me how he has been working hard to get the upcoming introductory genetics course online, especially given the increase in students (there are more than 1200 currently enrolled in the course). I said, “You must be looking forward to the end of this crisis when we can start teaching in‐person again.” His response has had a lasting effect on me. “I’m not so sure things will go back to the way they were,” he said. “A lot of students are enjoying online learning—or are at least finding it convenient and cost‐effective. Many are saving money by living at home and by not having to bus into campus every day and buy overpriced food. They like being able to watch the recorded lectures on their own schedule and at their own speed. Even after the current crisis ends, I think there be will be a strong push for continued online learning.” “You might be right,” I said, “but I sure hope not.”When we parted ways, I felt even more downtrodden. I reminded myself that I was lucky to have a great job and that I needed to be adaptable. If the future is online learning, so be it. I can become a connoisseur of Camtasia. I can learn to be creative and engaging over Zoom. I can master those microphone and camera settings. But I could not help thinking this is not what I signed up for. When the pandemic is over, I do not want to exist in a cyber campus with online students and online colleagues. I do not want my home to be a lecture hall. I want brick and mortar and real bums in real seats. I want to stand in line for 20 minutes outside the student union building for lukewarm coffee. I want to waste precious time walking to meetings and making small talk in the corridors. I want the thing that I fell in love with. Until COVID‐19 is defeated, we need to stay vigilant. But when the war is won, will university campuses return to being physical gathering points for learning, engagement and community building or virtual concepts in an online learning space? Whatever the answer, I know that if you are looking for Associate Professor David R. Smith, you will find him holding out in the Biological and Geological Sciences Building, room 3028. The hand‐written sign on the door will say, “Going down with the ship.”     

Cyclic ADP-ribose and the regulation of calcium-induced calcium release in eggs and cardiac myocytes

Cyclic ADP-ribose (cADPR) is a cyclic metabolite of NAD⁺ synthesised in cells and tissues expressing ADP-ribosyl cyclases. Although it was first discovered in sea-urchin egg extracts as a potent calcium mobilizing agent, subsequent studies have indicated that it may have a widespread action in the activation of calcium-release channels in such diverse systems as mammalian neurones, myocytes, blood cells, eggs, and plant microsomes. In this review we focus on recent work suggesting that cADPR enhances the sensitivity of ryanodine-sensitive calcium-release channels (RyRs) to activation by calcium, a phenomenon termed calcium-induced calcium release (CICR). Two roles for cADPR in calcium signaling are discussed. The first is as a classical second messenger where its levels are controlled by extracellular stimuli, and the second mode of cellular regulation is that the levels of intracellular cADPR may set the sensitivity of RyRs to activation by an influx of calcium in excitable cells. These two possible actions of cADPR are illustrated by considering the signal transduction events during the fertilization of the sea-urchin egg and the modulation of CICR during excitation-coupling in isolated guinea-pig ventricular myocytes, respectively.