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991.
Audrey Arnal Beata Ujvari Leonard Nunney Eric Solary Lucie Laplane François Bonhomme Marion Vittecoq Aurélie Tasiemski François Renaud Pascal Pujol Benjamin Roche Frédéric Thomas 《Evolution; international journal of organic evolution》2016,70(1):1-6
Similar to seemingly maladaptive genes in general, the persistence of inherited cancer‐causing mutant alleles in populations remains a challenging question for evolutionary biologists. In addition to traditional explanations such as senescence or antagonistic pleiotropy, here we put forward a new hypothesis to explain the retention of oncogenic mutations. We propose that although natural defenses evolve to prevent neoplasm formation and progression thus increasing organismal fitness, they also conceal the effects of cancer‐causing mutant alleles on fitness and concomitantly protect inherited ones from purging by purifying selection. We also argue for the importance of the ecological contexts experienced by individuals and/or species. These contexts determine the locally predominant fitness‐reducing risks, and hence can aid the prediction of how natural selection will influence cancer outcomes. 相似文献
992.
Improved white spruce (Picea glauca) genome assemblies and annotation of large gene families of conifer terpenoid and phenolic defense metabolism 下载免费PDF全文
René L. Warren Christopher I. Keeling Macaire Man Saint Yuen Anthony Raymond Greg A. Taylor Benjamin P. Vandervalk Hamid Mohamadi Daniel Paulino Readman Chiu Shaun D. Jackman Gordon Robertson Chen Yang Brian Boyle Margarete Hoffmann Detlef Weigel David R. Nelson Carol Ritland Nathalie Isabel Barry Jaquish Alvin Yanchuk Jean Bousquet Steven J. M. Jones John MacKay Inanc Birol Joerg Bohlmann 《The Plant journal : for cell and molecular biology》2015,83(2):189-212
993.
A subset of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) patients present pathological redistribution and aggregation of the nuclear protein fused in sarcoma (FUS) in the cytoplasm. Although FUS associates with the spliceosomal complex, no endogenous neuronal splicing targets have been identified. Here we identify Tau mRNA as a physiological splicing target of FUS. In mouse brain, FUS directly binds to Tau pre-mRNA, and knockdown of FUS in hippocampal neurons leads to preferential inclusion of Tau exons 3 and 10. FUS knockdown causes significant growth cone enlargement and disorganization reminiscent of Tau loss of function. These findings suggest that disturbed cytoskeletal function and enhanced expression of the neurodegeneration-associated Tau exon 10 might contribute to FTLD/ALS with FUS inclusions. 相似文献
994.
Background
Cellular processes occur within dynamic and multi-molecular compartments whose characterization requires analysis at high spatio-temporal resolution. Notable examples for such complexes are cell-matrix adhesion sites, consisting of numerous cytoskeletal and signaling proteins. These adhesions are highly variable in their morphology, dynamics, and apparent function, yet their molecular diversity is poorly defined.Methodology/Principal Findings
We present here a compositional imaging approach for the analysis and display of multi-component compositions. This methodology is based on microscopy-acquired multicolor data, multi-dimensional clustering of pixels according to their composition similarity and display of the cellular distribution of these composition clusters. We apply this approach for resolving the molecular complexes associated with focal-adhesions, and the time-dependent effects of Rho-kinase inhibition. We show here compositional variations between adhesion sites, as well as ordered variations along the axis of individual focal-adhesions. The multicolor clustering approach also reveals distinct sensitivities of different focal-adhesion-associated complexes to Rho-kinase inhibition.Conclusions/Significance
Multicolor compositional imaging resolves “molecular signatures” characteristic to focal-adhesions and related structures, as well as sub-domains within these adhesion sites. This analysis enhances the spatial information with additional “contents-resolved” dimensions. We propose that compositional imaging can serve as a powerful tool for studying complex multi-molecular assemblies in cells and for mapping their distribution at sub-micron resolution. 相似文献995.
Timothée Poisot Benjamin Baiser Jennifer A. Dunne Sonia Kéfi François Massol Nicolas Mouquet Tamara N. Romanuk Daniel B. Stouffer Spencer A. Wood Dominique Gravel 《Ecography》2016,39(4):384-390
The study of ecological networks is severely limited by 1) the difficulty to access data, 2) the lack of a standardized way to link meta‐data with interactions, and 3) the disparity of formats in which ecological networks themselves are stored and represented. To overcome these limitations, we have designed a data specification for ecological networks. We implemented a database respecting this standard, and released an R package (rmangal) allowing users to programmatically access, curate, and deposit data on ecological interactions. In this article, we show how these tools, in conjunction with other frameworks for the programmatic manipulation of open ecological data, streamlines the analysis process and improves replicability and reproducibility of ecological network studies. 相似文献
996.
997.
Christa L. Cortesio Benjamin J. Perrin David A. Bennin Anna Huttenlocher 《Molecular biology of the cell》2010,21(1):186-197
Growth factor stimulation induces the formation of dynamic actin structures known as dorsal ruffles. Mammalian actin-binding protein-1 (mAbp1) is an actin-binding protein that has been implicated in regulating clathrin-mediated endocytosis; however, a role for mAbp1 in regulating the dynamics of growth factor–induced actin-based structures has not been defined. Here we show that mAbp1 localizes to dorsal ruffles and is necessary for platelet-derived growth factor (PDGF)-mediated dorsal ruffle formation. Despite their structural similarity, we find that mAbp1 and cortactin have nonredundant functions in the regulation of dorsal ruffle formation. mAbp1, like cortactin, is a calpain 2 substrate and the preferred cleavage site occurs between the actin-binding domain and the proline-rich region, generating a C-terminal mAbp1 fragment that inhibits dorsal ruffle formation. Furthermore, mAbp1 directly interacts with the actin regulatory protein WASp-interacting protein (WIP) through its SH3 domain. Finally, we demonstrate that the interaction between mAbp1 and WIP is important in regulating dorsal ruffle formation and that WIP-mediated effects on dorsal ruffle formation require mAbp1. Taken together, these findings identify a novel role for mAbp1 in growth factor–induced dorsal ruffle formation through its interaction with WIP. 相似文献
998.
Moser Florian N. van Rijssel Jacco C. Ngatunga Benjamin Mwaiko Salome Seehausen Ole 《Hydrobiologia》2019,832(1):283-296
Hydrobiologia - Cichlids of the genus Oreochromis (“Tilapias”) are intensively used in aquaculture around the world. In many cases, when “Tilapia” were introduced for... 相似文献
999.
1000.
Kikani CK Antonysamy SA Bonanno JB Romero R Zhang FF Russell M Gheyi T Iizuka M Emtage S Sauder JM Turk BE Burley SK Rutter J 《The Journal of biological chemistry》2010,285(52):41034-41043
Per-Arnt-Sim (PAS) domain-containing protein kinase (PASK) is an evolutionary conserved protein kinase that coordinates cellular metabolism with metabolic demand in yeast and mammals. The molecular mechanisms underlying PASK regulation, however, remain unknown. Herein, we describe a crystal structure of the kinase domain of human PASK, which provides insights into the regulatory mechanisms governing catalysis. We show that the kinase domain adopts an active conformation and has catalytic activity in vivo and in vitro in the absence of activation loop phosphorylation. Using site-directed mutagenesis and structural comparison with active and inactive kinases, we identified several key structural features in PASK that enable activation loop phosphorylation-independent activity. Finally, we used combinatorial peptide library screening to determine that PASK prefers basic residues at the P-3 and P-5 positions in substrate peptides. Our results describe the key features of the PASK structure and how those features are important for PASK activity and substrate selection. 相似文献