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101.
Erica L. Gorenberg Sofia Massaro Tieze Betül Yücel Helen R. Zhao Vicky Chou Gregory S. Wirak Susumu Tomita TuKiet T. Lam Sreeganga S. Chandra 《PLoS biology》2022,20(3)
Loss-of-function mutations in the depalmitoylating enzyme palmitoyl protein thioesterase 1 (PPT1) cause neuronal ceroid lipofuscinosis (NCL), a devastating neurodegenerative disease. The substrates of PPT1 are largely undescribed, posing a limitation on molecular dissection of disease mechanisms and therapeutic development. Here, we provide a resource identifying >100 novel PPT1 substrates. We utilized Acyl Resin-Assisted Capture (Acyl RAC) and mass spectrometry to identify proteins with increased in vivo palmitoylation in PPT1 knockout (KO) mouse brains. We then validated putative substrates through direct depalmitoylation with recombinant PPT1. This stringent screen elucidated diverse PPT1 substrates at the synapse, including channels and transporters, G-protein–associated molecules, endo/exocytic components, synaptic adhesion molecules, and mitochondrial proteins. Cysteine depalmitoylation sites in transmembrane PPT1 substrates frequently participate in disulfide bonds in the mature protein. We confirmed that depalmitoylation plays a role in disulfide bond formation in a tertiary screen analyzing posttranslational modifications (PTMs). Collectively, these data highlight the role of PPT1 in mediating synapse functions, implicate molecular pathways in the etiology of NCL and other neurodegenerative diseases, and advance our basic understanding of the purpose of depalmitoylation.Unbiased proteomics with acyl resin-assisted capture reveals diverse novel substrates of the depalmitoylating enzyme palmitoyl protein thioesterase 1 (PPT1) at the synapse, with potential implications for the pathogenesis of neuronal ceroid lipofuscinosis, disulfide bond formation, synaptic adhesion and additional critical synaptic functions. 相似文献
102.
Anne M. Bronikowski Richard P. Meisel Peggy R. Biga James
R. Walters Judith E. Mank Erica Larschan Gerald S. Wilkinson Nicole Valenzuela Ashley Mae Conard Joo Pedro de Magalhes Jingyue
Duan Amy E. Elias Tony Gamble Rita
M. Graze Kristin E. Gribble Jill A. Kreiling Nicole C. Riddle 《Aging cell》2022,21(2)
Sex differences in aging occur in many animal species, and they include sex differences in lifespan, in the onset and progression of age‐associated decline, and in physiological and molecular markers of aging. Sex differences in aging vary greatly across the animal kingdom. For example, there are species with longer‐lived females, species where males live longer, and species lacking sex differences in lifespan. The underlying causes of sex differences in aging remain mostly unknown. Currently, we do not understand the molecular drivers of sex differences in aging, or whether they are related to the accepted hallmarks or pillars of aging or linked to other well‐characterized processes. In particular, understanding the role of sex‐determination mechanisms and sex differences in aging is relatively understudied. Here, we take a comparative, interdisciplinary approach to explore various hypotheses about how sex differences in aging arise. We discuss genomic, morphological, and environmental differences between the sexes and how these relate to sex differences in aging. Finally, we present some suggestions for future research in this area and provide recommendations for promising experimental designs. 相似文献
103.
Erica L. Larson C. Guilherme Becker Eliana R. Bondra Richard G. Harrison 《Ecology and evolution》2013,3(4):985-1002
Hybrid zones provide insight into the nature of species boundaries and the evolution of barriers to gene exchange. Characterizing multiple regions within hybrid zones is essential for understanding both their history and current dynamics. Here, we describe a previously uncharacterized region of a well‐studied hybrid zone between two species of field crickets, Gryllus pennsylvanicus and G. firmus. We use a combination of mitochondrial DNA sequencing, morphological data, and modeling of environmental variables to identify the ecological factors structuring the hybrid zone and define patterns of hybridization and introgression. We find an association between species distribution and natural habitat; Gryllus pennsylvanicus occupies natural habitat along forest edges and natural clearings, whereas G. firmus occupies more disturbed areas in agricultural and suburban environments. Hybridization and introgression occur across patch boundaries; there is evidence of substantial admixture both in morphological characters and mtDNA, over a broad geographic area. Nonetheless, the distribution of morphological types is bimodal. Given that F1 hybrids are viable and fertile in the lab, this suggests that strong pre‐zygotic barriers are operating in this portion of the hybrid zone. 相似文献
104.
105.
Voyles J Richards-Hrdlicka K Cashins SD Rosenblum EB Hyatt AD Berger L Skerratt LF 《Diseases of aquatic organisms》2010,92(2-3):109-112
The fungal pathogen Batrachochytrium dendrobatidis (Bd) causes the disease chytridiomycosis, which is lethal to many species of amphibians worldwide. Many studies have investigated the epidemiology of chytridiomycosis in amphibian populations, but few have considered possible host-pathogen coevolution. More specifically, investigations focused on the evolution of Bd, and the link with Bd virulence, are needed. Such studies, which may be important for conservation management of amphibians, depend on access to Bd isolates. Here we provide a summary of known Bd isolates that have been collected and archived in various locations around the world. Of 257 Bd isolates, we found that 53% originate from ranids in the United States. In many cases, detailed information on isolate origin is unavailable, and it is unknown how many isolates are cryo-archived. We suggest the creation of a centralized database of isolate information, and we urge researchers and managers to isolate and archive Bd to facilitate future research on chytridiomycosis. 相似文献
106.
107.
108.
Erica P. Gunderson Charles P. Quesenberry Cora E. Lewis Ai‐Lin Tsai Barbara Sternfeld Delia Smith West Steve Sidney 《Obesity (Silver Spring, Md.)》2004,12(12):2041-2053
Objective: To prospectively evaluate whether childbearing leads to development of overweight in women and to evaluate the role of other known risk factors. Research Methods and Procedures: A prospective, multicenter observational study, the Coronary Artery Risk Development in Young Adults (CARDIA) Study from 1986 to 1996, examined subjects at baseline and in follow‐up years 2, 5, 7, and 10. Included were 998 (328 black and 670 white) nulliparous women, age 18‐30 years, who were not overweight at baseline. Relative odds for incident overweight (BMI ≥ 25 kg/m2) associated with parity change (0, 1, or 2+) and risk factors were estimated using discrete‐time survival models adjusted for baseline and time‐dependent covariates. Results: Parity change‐association with development of overweight depended on smoking habit (interaction, p < 0.001). In multivariate adjusted models, 1 and 2+ births vs. 0, respectively, were associated with increased risk for development of overweight among never smokers [odds ratio (OR) = 2.66; 95% confidence interval (CI): 1.80, 3.93, and 2.10, 95% CI: 1.24, 3.56] and decreased risk among current smokers (OR = 0.41; 95% CI: 0.17, 0.96, and 0.36, 95% CI: 0.08, 1.65). Risk was increased for black vs. white race (OR = 3.49; 95% CI: 2.59, 4.69), frequent weight cycling (OR = 1.45; 95% CI: 1.03, 2.04), and high school education or less (OR = 2.21; 95% CI: 1.50, 3.26) and was decreased for highest physical activity quartile (OR = 0.62; 95% CI: 0.43, 0.90). Discussion: Childbearing contributes to development of overweight in nonsmokers but not in smokers, where development of overweight is less likely in women who bear children. Race, education, and behaviors are important factors in development of overweight in young women. 相似文献
109.
Barbara Assenzio Erica L. Martin Edgaras Stankevicius Federica Civiletti Marco Fontanella Riccardo Boccaletti Maurizio Berardino AnnaTeresa Mazzeo Alessandro Ducati Ulf Simonsen Luciana Mascia 《PloS one》2015,10(1)
Introduction
Previous studies have suggested that cerebrospinal fluid from patients with subarachnoid hemorrhage (SAH) leads to pronounced vasoconstriction in isolated arteries. We hypothesized that only cerebrospinal fluid from SAH patients with vasospasm would produce an enhanced contractile response to endothelin-1 in rat cerebral arteries, involving both endothelin ETA and ETB receptors.Methods
Intact rat basilar arteries were incubated for 24 hours with cerebrospinal fluid from 1) SAH patients with vasospasm, 2) SAH patients without vasospasm, and 3) control patients. Arterial segments with and without endothelium were mounted in myographs and concentration-response curves for endothelin-1 were constructed in the absence and presence of selective and combined ETA and ETB receptor antagonists. Endothelin concentrations in culture medium and receptor expression were measured.Results
Compared to the other groups, the following was observed in arteries exposed to cerebrospinal fluid from patients with vasospasm: 1) larger contractions at lower endothelin concentrations (p<0.05); 2) the increased endothelin contraction was absent in arteries without endothelium; 3) higher levels of endothelin secretion in the culture medium (p<0.05); 4) there was expression of ETA receptors and new expression of ETB receptors was apparent; 5) reduction in the enhanced response to endothelin after ETB blockade in the low range and after ETA blockade in the high range of endothelin concentrations; 6) after combined ETA and ETB blockade a complete inhibition of endothelin contraction was observed.Conclusions
Our experimental findings showed that in intact rat basilar arteries exposed to cerebrospinal fluid from patients with vasospasm endothelin contraction was enhanced in an endothelium-dependent manner and was blocked by combined ETA and ETB receptor antagonism. Therefore we suggest that combined blockade of both receptors may play a role in counteracting vasospasm in patients with SAH. 相似文献110.
Kerry Bohl Stricker Philip F. Harmon Erica M. Goss Keith Clay S. Luke Flory 《Ecology letters》2016,19(4):469-477
Emerging pathogens are a growing threat to human health, agriculture and the diversity of ecological communities but may also help control problematic species. Here we investigated the diversity, distribution and consequences of emerging fungal pathogens infecting an aggressive invasive grass that is rapidly colonising habitats throughout the eastern USA. We document the recent emergence and accumulation over time of diverse pathogens that are members of a single fungal genus and represent multiple, recently described or undescribed species. We also show that experimental suppression of these pathogens increased host performance in the field, demonstrating the negative effects of emerging pathogens on invasive plants. Our results suggest that invasive species can facilitate pathogen emergence and amplification, raising concerns about movement of pathogens among agricultural, horticultural, and wild grasses. However, one possible benefit of pathogen accumulation is suppression of aggressive invaders over the long term, potentially abating their negative impacts on native communities. 相似文献