Biological clock: the oscillator of gene expression

正The 2017 Nobel prize in physiology or medicine was awarded to the discoveries of genes and molecular mechanisms of the circadian rhythm,which is any biological process that oscillates with a period of about 24 h.Three scientists from the United States,Jeffrey C.Hall,Michael Rosbash,and Michael W.Young,shared the award.This work is of great theoretical value in understanding the nature of life and the interactions of life with its environments,and also has important application value in guiding the treatment     

Opening new doors for understanding eukaryotic RNA splicing

<正>Since the central dogma of molecular biology was proposed by Francis Crick in 1956,many fundamental discoveries have been made to strengthen or expand the theory for gene expression.Nowadays,we know that genetic information flow in a cell is a far more complicated process than the original succinct but explicit version.We now know that     

An overview of rice genetics research in China

正Congratulations to the Genetics Society of China on their 40~(th) anniversary! Genetics has expanded in scope in that time frame and has penetrated into many areas of biology, medicine and agriculture. Genetics is poised to continue that trajectory into the future with promises of new understanding and new technologies for the benefit to society. Here, we will highlight some of the     

Advances in cell lineage reprogramming

As a milestone breakthrough of stem cell and regenerative medicine in recent years,somatic cell reprogramming has opened up new applications of regenerative medicine by breaking through the ethical shackles of embryonic stem cells.However,induced pluripotent stem(iPS) cells are prepared with a complicated protocol that results in a low reprogramming rate.To obtain differentiated target cells,iPS cells and embryonic stem cells still need to be induced using step-by-step procedures.The safety of induced target cells from iPS cells is currently a further concerning matter.More broadly conceived is lineage reprogramming that has been investigated since 1987.Adult stem cell plasticity,which triggered interest in stem cell research at the end of the last century,can also be included in the scope of lineage reprogramming.With the promotion of iPS cell research,lineage reprogramming is now considered as one of the most promising fields in regenerative medicine,will hopefully lead to customized,personalized therapeutic options for patients in the future.     

Double-stranded DNA breaks and gene functions in recombination and meiosis

Meiotic prophase I is a long and complex phase. Homologous recombination is an important process that occurs between homologous chromosomes during meiotic prophase I. Formation of chiasmata, which hold homologous chromosomes together until the metaphase I to anaphase I transition, is critical for proper chromosome segregation. Recent studies have suggested that the SPO 11 proteins have conserved functions in a number of organisms in generating sites of double-stranded DNA breaks （DSBs） that are thought to be the starting points of homologous recombination. Processing of these sites of DSBs requires the function of RecA homologs, such as RAD5 1, DMC 1, and others, as suggested by mutant studies; thus the failure to repair these meiotic DSBs results in abnormal chromosomal alternations, leading to disrupted meiosis. Recent discoveries on the functions of these RecA homologs have improved the understanding of the mechanisms underlying meiotic homologous recombination.     

Arsenic prepared by Chinese alchemist-pharmacists

正Dear Editor,The discovery of artemisinin is just one of the gifts from traditional Chinese medicine to the world.Clinical studies have shown that arsenic trioxide,an ancient drug used in     

Magnetic resonance imaging in personalized medicine

正Continued biomedical advances and increased demands on quality health care have led to a new era of personalized medicine—a concept of medicine that uses specific information to an individual to help diagnose disease,plan treatment,assess treatment efficacy,and/or predict prognosis.This concept has evolved from the idea of"patient-centered care",which intends to shift the focus of health care from diseases to patients(Abujudeh et al.,2016).Medical imaging is essential in the practice of modern medicine,and its role in personalized medicine has never been greater.In particular,magnetic resonance(MR)     

Ecdysteroids： the overlooked sex steroids of insects？ Males： the black box

The paradigm, still around in textbooks, that ＇in insects sex is strictly genetic, thus that they do not have sex hormones＇, is mainly based on a wrong interpretation of the ＇gynandromorph argument＇. It is no longer tenable. Given the fact that vertebrates and invertebrates probably had a common, sexually reproducing ancestor, there is no reason to assume that only vertebrates need sex hormones. The major function of sex hormones is to inform the somatoplasm about developmental changes that take place in the gonads. In contrast to juvenile hormone and neuropeptides, ecdysteroids meet all criteria to act as sex hormones, which was probably their ancient role. Their much better documented role in moulting and metamorphosis was a secondary acquisition that enabled arthropods to cope with growth problems, imposed by a rigid cuticle. Female insects use 20-hydroxyecdysone （20E）, secreted by the follicle cells of the ovary, in a similar way as females of egg-laying vertebrates use estrogens. For a variety of reasons, the possibility that ecdysteroids, in particular ecdysone （E）, might also act as sex hormones in male insects, thus as the counterpart of testosterone of vertebrates, has been very much overlooked. Thanks to the recent discovery of the molecular basis of the haploid-diploid system of sex determination in the honeybee, the characterization of Halloween genes, proteomics, RNAi and so on, it now becomes possible to verify whether in insects, as with vertebrates, males are the endocrinologically default gender form.     

Control of stem cell fate by engineering their micro and nanoenvironment

Stem cells are capable of long-term self-renewal and differentiation into specialised cell types, making them an ideal candidate for a cell source for regenerative medicine. The control of stem cell fate has become a major area of interest in the field of regenerative medicine and therapeutic intervention. Conventional methods of chemically inducing stem cells into specific lineages is being challenged by the advances in biomaterial technology, with evidence highlighting that material properties are capable of driving stem cell fate. Materials are being designed to mimic the clues stem cells receive in their in vivo stem cell niche including topographical and chemical instructions. Nanotopographical clues that mimic the extracellular matrix(ECM) in vivo have shown to regulate stem cell differentiation. The delivery of ECM components on biomaterials in the form of short peptides sequences has also proved successful in directing stem cell lineage. Growth factors responsible for controlling stem cell fate in vivo have also been delivered via biomaterials to provide clues to determine stem cell differentiation. An alternative approach to guide stem cells fate is to provide genetic clues including delivering DNA plasmids and small interfering RNAs via scaffolds. This review, aims to provide an overview of the topographical, chemical and molecular clues that biomaterials can provide to guide stem cell fate. The promising features and challenges of such approaches will be highlighted, to provide directions for future advancements in this exciting area of stem cell translation for regenerative medicine.     

Medical genetics: Towards precision medicine

正Medical genetics is defined as a branch of medicine that involves the diagnosis and management of hereditary disorders by applying genetics to medical care.The Human Genome Project,initiated in1990 and completed in 2004,has profoundly changed biology and is rapidly catalyzing a transformation of medical genetics and medicine in general(Collins and McKusick,2001;Green and Guyer,2011).Before the Human Genome Project,researchers     

Obesity and weight loss could alter the properties of adipose stem cells?

The discovery that adipose tissue represents an interesting source of multipotent stem cells has led to many studies exploring the clinical potential of these cells in cell-based therapies. Recent advances in understanding the secretory capacity of adipose tissue and the role of adipokines in the development of obesity and associated disorders have added a new dimension to the study of adipose tissue biology in normal and diseased states. Subcutaneous adipose tissue forms the interface between the clinical application of regenerative medicine and the establishment of the pathological condition of obesity. These two facets of adipose tissue should be understood as potentially related phenomena. Because of the functional characteristics of adipose stem cells, these cells represent a fundamental tool for understanding how these two facets are interconnected and could be important for therapeutic applications. In fact, adipose tissue stem cells have multiple functions in obesity related to adipogenic, angiogenic and secretory capacities. In addition, we have also previously described a predominance of larger blood vessels and an adipogenic memory in the subcutaneous adipose tissue after massive weight loss subsequent to bariatric surgery(ex-obese patients). Understanding the reversibility of the behavior of adipose stem cells in obeses and in weight loss is relevant to both physiological studies and the potential use of these cells in regenerative medicine.     

Suggestions to the hepatitis B vaccine events

<正>The media has reported several neonatal death events recently,and it is suspected that these events are related to improper vaccination.This is a deeply regrettable occurrence.Regarding the current situation,we suggest relevant national departments lead and organize experts in areas of clinical medicine,epidemiology,disease control,legal medicine,pharmacy,bio-product research and development,quality control and other related fields to establish a joint investigation team to conduct an investigation quickly and independently to determine the causes as soon as possible to reassure the public.Currently,the public is focused on whether the vaccine is safe.Therefore,it should be first made clear whether the deaths were caused by vaccination.     

Tongue as a first-line immune organ?

The tongue is an organ strategically situated at the beginning of the gastrointestinal(Gl)system,yet it has been remarkably understudied.Not only there is no separate subspecialty dedicated to the tongue,it is even excluded from 27 human organs/tissues thoroughly archived in the NCBI gene expression database.Almost none of my physician colleagues in Western medicine have paid attention to it,except a few who study tongue cancer.The tongue is typically described as a muscular organ important for taste,mastication,speech and sensation.Other than its development,anatomy/gross structural analyses and taste function(for recent reviews,see Roper and Chaudhari,2017),the human tongue is poorly studied in Western medicine,in particular,in terms of its roles in systemic diseases.In traditional Chinese medicine(TCM),however,the tongue holds a special place.Assessing the“tongue coating”,"tongue body”and morphological features is one of the most critical skills that TCM doctors have relied on for disease diagnoses for thousands of years before the advent of Western Medicine.     

Cell polarity: Regulators and mechanisms in plants

Cell polarity plays an important role in a wide range of biological processes in plant growth and development.Cell polarity is manifested as the asymmetric distribution of molecules,for example,proteins and lipids,at the plasma membrane and inside of a cell.Here,we summarize a few polarized proteins that have been characterized in plants and we review recent advances towards understanding the molecular mechanism for them to polarize at the plasma membrane.Multiple mechanisms,including membrane trafficking,cytoskeletal activities,and protein phosphorylation,and so forth define the polarized plasma membrane domains.Recent discoveries suggest that the polar positioning of the proteo-lipid membrane domain may instruct the formation of polarity complexes in plants.In this review,we highlight the factors and regulators for their functions in establishing the membrane asymmetries in plant development.Furthermore,we discuss a few outstanding questions to be addressed to better understand the mechanisms by which cell polarity is regulated in plants.     

Melatonin in the seasonal response of the aphid Acyrthosiphon pisum

Aphids display life cycles largely determined by the photoperiod.During the warm long-day seasons.most aphid species reproduce by viviparous parthenogenesis.The shortening of the photoperiod in autumn induces a switch to sexual reproduction.Males and sexual females mate to produce overwintering resistant eggs.In addition to this full life cycle(holocycle),there are anholocyelic lineages that do not respond to changes in photoperiod and reproduce continuously by parthenogenesis.The molecular or hormonal events that trigger the scasonal response(i.c,induction of the sexual phenotypes)are still unknown.Although circadian synthesis of melatonin is known to play a key role in vertebrate photoperiodism,the involvement of the circadian clock and/or of the hor-mone melatonin in insect seasonal responses is not so well established.Here we show that melatonin levels in the aphid Acyrthosiphon pisum are significantly higher in holocyclice aphids reared under short days than under long days,while no differences were found between anholoeyelic aphids under the same conditions.We also found that melatonin is localized in the aphid suboesophageal ganglion(SOG)and in the thoracic ganglionic mass(TGM).In analogy to vertcbrates,insect-type arylalkxylamine N-acetyltransferases(i-AANATs)are thought to play a key role in melatonin synthesis.We measured the expression of four I-AANAT genes identified in A.pisum and localized two of them in situ in the insect central nervous systems(CNS).Levels of expression of these genes were compatible with the quantities of melatonin observed.Moreover,like melatonin,expression of these genes was found in the SOG and the TGM.     

Recent advances in plant centromere biology

The centromere, which is one of the essential parts of a chromosome, controls kinetochore formation and chromosome segregation during mitosis and meiosis. While centromere function is conserved in eukaryotes, the centromeric DNA sequences evolve rapidly and have few similarities among species. The histone H3 variant CENH3(CENP-A in human), which mostly exists in centromeric nucleosomes, is a universal active centromere mark in eukaryotes and plays an essential role in centromere identity determination. The relationship between centromeric DNA sequences and centromere identity determination is one of the intriguing questions in studying centromere formation. Due to the discoveries in the past decades, including "neocentromeres" and "centromere inactivation", it is now believed that the centromere identity is determined by epigenetic mechanisms. This review will present recent progress in plant centromere biology.     

Introduction of Standard for the operation of European Biological Resource Centers

(Continued)The equipment and environment in the premises must conform to European legislation meeting quality standards as well as health and safely requirements. The following conditions must be met:Ⅰ. BRC laboratories are clean and well itⅡ. No source of excessive or unusual microbial contamination is introducedⅢ. Adequate bench and storage space is provided, consistent with the type and volume of work,Ⅳ. An appropriate containment facility is available to protect the work and worker from potential release of aerosols containing microorganisms or hazardous chemicals.     

Biomimetics of Campaniform Sensilla： Measuring Strain from the Deformation of Holes

We present a bio-inspired strategy for designing embedded strain sensors in space structures. In insects, the campaniform sensillum is a hole extending through the cuticle arranged such that its shape changes in response to loads. The shape change is rotated through 90° by the suspension of a bell-shaped cap whose deflection is detected by a cell beneath the cuticle. It can be sensitive to displacements of the order of 1 nm. The essential morphology, a hole formed in a plate of fibrous composite mate- rial, was modelled by Skordos et al. who showed that global deformation of the plate （which can be flat, curved or a tube） induces higher local deformation of the hole due to its locally higher compliance. Further developments reported here show that this approach can be applied to groups of holes relative to their orientation. , The morphology of the sensillum in insects suggests that greater sensitivity can be achieved by arranging several holes in a regular pattern; that if the hole is oval it can be ＂aimed＂ to sense specific strain directions; and that either by controlling the shape of the hole or its relationship with other holes it can have a tuned response to dynamic strains. We investigate space applications in which novel bio-inspired strain sensors could successfully be used.