排序方式: 共有89条查询结果,搜索用时 15 毫秒
61.
Lipinski MJ Froenicke L Baysac KC Billings NC Leutenegger CM Levy AM Longeri M Niini T Ozpinar H Slater MR Pedersen NC Lyons LA 《Genomics》2008,91(1):12-21
The diaspora of the modern cat was traced with microsatellite markers from the presumed site of domestication to distant regions of the world. Genetic data were derived from over 1100 individuals, representing 17 random-bred populations from five continents and 22 breeds. The Mediterranean was reconfirmed to be the probable site of domestication. Genetic diversity has remained broad throughout the world, with distinct genetic clustering in the Mediterranean basin, Europe/America, Asia and Africa. However, Asian cats appeared to have separated early and expanded in relative isolation. Most breeds were derived from indigenous cats of their purported regions of origin. However, the Persian and Japanese bobtail were more aligned with European/American than with Mediterranean basin or Asian clusters. Three recently derived breeds were not distinct from their parental breeds of origin. Pure breeding was associated with a loss of genetic diversity; however, this loss did not correlate with breed popularity or age. 相似文献
62.
Corbin JG Gaiano N Juliano SL Poluch S Stancik E Haydar TF 《Journal of neurochemistry》2008,106(6):2272-2287
The mammalian telencephalon, which comprises the cerebral cortex, olfactory bulb, hippocampus, basal ganglia, and amygdala, is the most complex and intricate region of the CNS. It is the seat of all higher brain functions including the storage and retrieval of memories, the integration and processing of sensory and motor information, and the regulation of emotion and drive states. In higher mammals such as humans, the telencephalon also governs our creative impulses, ability to make rational decisions, and plan for the future. Despite its massive complexity, exciting work from a number of groups has begun to unravel the developmental mechanisms for the generation of the diverse neural cell types that form the circuitry of the mature telencephalon. Here, we review our current understanding of four aspects of neural development. We first begin by providing a general overview of the broad developmental mechanisms underlying the generation of neuronal and glial cell diversity in the telencephalon during embryonic development. We then focus on development of the cerebral cortex, the most complex and evolved region of the brain. We review the current state of understanding of progenitor cell diversity within the cortical ventricular zone and then describe how lateral signaling via the Notch-Delta pathway generates specific aspects of neural cell diversity in cortical progenitor pools. Finally, we review the signaling mechanisms required for development, and response to injury, of a specialized group of cortical stem cells, the radial glia, which act both as precursors and as migratory scaffolds for newly generated neurons. 相似文献
63.
Exploratory data-driven multivariate analysis provides a means of investigating underlying structure in complex data. To explore the stability of multivariate data modeling, we have applied a common method of multivariate modeling (factor analysis) to the Genetic Analysis Workshop 13 (GAW13) Framingham Heart Study data. Given the longitudinal nature of the data, multivariate models were generated independently for a number of different time points (corresponding to cross-sectional clinic visits for the two cohorts), and compared. In addition, each multivariate model was used to generate factor scores, which were then used as a quantitative trait in variance component-based linkage analysis to investigate the stability of linkage signals over time. We found surprisingly good correlation between factor models (i.e., predicted factor structures), maximum LOD scores, and locations of maximum LOD scores (0.81< rho <0.94 for factor scores; rho >0.99 for peak locations; and 0.67< rho <0.93 for peak LOD scores). Furthermore, the regions implicated by linkage analysis with these factor scores have also been observed in other studies, further validating our exploratory modeling. 相似文献
64.
Modelling and projecting the response of local assemblage composition to land use change across Colombia 下载免费PDF全文
Susy Echeverría‐Londoño Tim Newbold Lawrence N. Hudson Sara Contu Samantha L. L. Hill Igor Lysenko Enrique Arbeláez‐Cortés Inge Armbrecht Teun Boekhout Jimmy Cabra‐García Yamileth Dominguez‐Haydar Guiomar Nates‐Parra Doris L. Gutiérrez‐Lamus Diego Higuera Paola Johanna Isaacs‐Cubides Carlos A. López‐Quintero Eliana Martinez Daniel Rafael Miranda‐Esquivel Luis Eduardo Navarro‐Iriarte Jorge Ari Noriega Samuel Eduardo Otavo Alejandro Parra‐H Katja Poveda Martha P. Ramirez‐Pinilla Juan Carlos Rey‐Velasco Loreta Rosselli Allan H. Smith‐Pardo José Nicolás Urbina‐Cardona Andy Purvis 《Diversity & distributions》2016,22(11):1099-1111
65.
An anchored restriction-mapping approach applied to the genetic analysis of the Anopheles gambiae malaria vector complex 1 总被引:1,自引:0,他引:1
We introduce here a simple approach for rapidly determining restriction
maps for a number of regions of a genome; this involves "anchoring" a map
with a rare restriction site (in this case the seldom-cutting EagI)
followed by partial digestion of a frequent-cutting enzyme (e.g., Sau 3A).
We applied this technology to five species of the Anopheles gambiae
complex. In a single Southern blot we obtained about a 15-kb restriction
map each for the mtDNA, rRNA gene, and a scnDNA region for each of five
species. Phylogenetic analyses of these regions yield trees at odds with
the more traditional chromosome inversion-based trees. The value of the
approach for systematic purposes is the ease with which several large,
independent regions of the genome can be quickly assayed for molecular
variation.
相似文献
66.
Theoretical considerations have shown that the five possible overlapping
reading-frame configurations differ significantly in their coding
flexibility and thus in their information content (Siegel and Fitch 1980;
Smith and Waterman 1980). Contrary to expectation, the overlapping frame
configuration allowing the greatest coding flexibility is rarely seen,
whereas one of the most constraining is common. We point out here that this
overlapping reading-frame paradox and an observed but unexplained
preference in coding regions for a pyrimidine-purine at codon boundaries
(Shepherd 1981; Jones and Kafatos 1982; Smith et al. 1983) are intimately
linked. The codon boundary preference, which may be related to translation
efficiency or accuracy, places constraints on the evolution of overlapping
coding regions. These considerations may help identify actual coding
regions in DNA sequences. We have analyzed five sequenced (enteric)
bacterial insertion sequences for codon boundary incidences and
reading-frame configurations and find that they are consistent with these
proposed constraints.
相似文献
67.
Haydar ?elik Kamal P. Sajwan Saravana P. Selvanathan Benjamin J. Marsh Amrita V. Pai Yasemin Saygideger Kont Jenny Han Tsion Z. Minas Said Rahim Hayriye Verda Erkizan Jeffrey A. Toretsky Aykut üren 《Molecular and cellular biology》2015,35(18):3145-3162
Ezrin is a key regulator of cancer metastasis that links the extracellular matrix to the actin cytoskeleton and regulates cell morphology and motility. We discovered a small-molecule inhibitor, NSC305787, that directly binds to ezrin and inhibits its function. In this study, we used a nano-liquid chromatography-tandem mass spectrometry (nano-LC–MS-MS)-based proteomic approach to identify ezrin-interacting proteins that are competed away by NSC305787. A large number of the proteins that interact with ezrin were implicated in protein translation and stress granule dynamics. We validated direct interaction between ezrin and the RNA helicase DDX3, and NSC305787 blocked this interaction. Downregulation or long-term pharmacological inhibition of ezrin led to reduced DDX3 protein levels without changes in DDX3 mRNA. Ectopic overexpression of ezrin in low-ezrin-expressing osteosarcoma cells caused a notable increase in DDX3 protein levels. Ezrin inhibited the RNA helicase activity of DDX3 but increased its ATPase activity. Our data suggest that ezrin controls the translation of mRNAs preferentially with a structured 5′ untranslated region, at least in part, by sustaining the protein level of DDX3 and/or regulating its function. Therefore, our findings suggest a novel function for ezrin in regulation of gene translation that is distinct from its canonical role as a cytoskeletal scaffold at the cell membrane. 相似文献
68.
Disruption of adaptor protein 2μ (AP‐2μ) in cochlear hair cells impairs vesicle reloading of synaptic release sites and hearing 下载免费PDF全文
Zhizi Jing Andreas Neef Natalia H Revelo Hanan Al‐Moyed Sandra Meese Sonja M Wojcik Iliana Panou Haydar Bulut Peter Schu Ralf Ficner Ellen Reisinger Silvio O Rizzoli Jakob Neef Nicola Strenzke Volker Haucke Tobias Moser 《The EMBO journal》2015,34(21):2686-2702
Active zones (AZs) of inner hair cells (IHCs) indefatigably release hundreds of vesicles per second, requiring each release site to reload vesicles at tens per second. Here, we report that the endocytic adaptor protein 2μ (AP‐2μ) is required for release site replenishment and hearing. We show that hair cell‐specific disruption of AP‐2μ slows IHC exocytosis immediately after fusion of the readily releasable pool of vesicles, despite normal abundance of membrane‐proximal vesicles and intact endocytic membrane retrieval. Sound‐driven postsynaptic spiking was reduced in a use‐dependent manner, and the altered interspike interval statistics suggested a slowed reloading of release sites. Sustained strong stimulation led to accumulation of endosome‐like vacuoles, fewer clathrin‐coated endocytic intermediates, and vesicle depletion of the membrane‐distal synaptic ribbon in AP‐2μ‐deficient IHCs, indicating a further role of AP‐2μ in clathrin‐dependent vesicle reformation on a timescale of many seconds. Finally, we show that AP‐2 sorts its IHC‐cargo otoferlin. We propose that binding of AP‐2 to otoferlin facilitates replenishment of release sites, for example, via speeding AZ clearance of exocytosed material, in addition to a role of AP‐2 in synaptic vesicle reformation. 相似文献
69.
70.
Julie Newman Haydar Karakaya David J. Scanlan Nicholas H. Mann 《FEMS microbiology letters》1995,133(1-2):187-193
Abstract The region of the genome encoding the glucose-6-phosphate dehydrogenase gene zwf was analysed in a unicellular cyanobacterium, Synechococcus sp. PCC 7942, and a filamentous, heterocystous cyanobacterium, Anabaena sp. PCC 7120. Comparison of cyanobacterial zwf sequences revealed the presence of two absolutely conserved cysteine residues which may be implicated in the light/dark control of enzyme activity. The presence in both strains of a gene fbp , encoding fructose-1,6-bisphosphatase, upstream from zwf strongly suggests that the oxidative pentose phosphate pathway in these organisms may function to completely oxidize glucose 6-phosphate to CO2 . The amino acid sequence of fructose-1,6-bisphosphatase does not support the idea of its light activation by a thiol/disulfide exchange mechanism. In the case of Anabaena sp. PCC 7120, the tal gene, encoding transaldolase, lies between zwf and fbp . 相似文献