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901.
A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin 总被引:3,自引:0,他引:3
Recent fossil discoveries have substantially reduced the morphological gap between non-avian and avian dinosaurs, yet avians
including Archaeopteryx differ from non-avian theropods in their limb proportions. In particular, avians have proportionally longer and more robust
forelimbs that are capable of supporting a large aerodynamic surface. Here we report on a new maniraptoran dinosaur, Anchiornis huxleyi gen. et sp. nov., based on a specimen collected from lacustrine deposits of uncertain age in western Liaoning, China. With
an estimated mass of 110 grams, Anchiornis is the smallest known non-avian theropod dinosaur. It exhibits some wrist features indicative of high mobility, presaging
the wing-folding mechanisms seen in more derived birds and suggesting rapid evolution of the carpus. Otherwise, Anchiornis is intermediate in general morphology between non-avian and avian dinosaurs, particularly with regard to relative forelimb
length and thickness, and represents a transitional step toward the avian condition. In contrast with some recent comprehensive
phylogenetic analyses, our phylogenetic analysis incorporates subtle morphological variations and recovers a conventional
result supporting the monophyly of Avialae.
Supported by Hundred Talents Project of the Chinese Academy of Sciences, National Natural Science Foundation of China (Grant
Nos. 40125006, 40472018), and National Basic Research Program of China (Grant No. 2006CB806400) 相似文献
902.
Parvari R Hershkovitz E Grossman N Gorodischer R Loeys B Zecic A Mortier G Gregory S Sharony R Kambouris M Sakati N Meyer BF Al Aqeel AI Al Humaidan AK Al Zanhrani F Al Swaid A Al Othman J Diaz GA Weiner R Khan KT Gordon R Gelb BD;HRD/Autosomal Recessive Kenny-Caffey Syndrome Consortium 《Nature genetics》2002,32(3):448-452
The syndrome of congenital hypoparathyroidism, mental retardation, facial dysmorphism and extreme growth failure (HRD or Sanjad-Sakati syndrome; OMIM 241410) is an autosomal recessive disorder reported almost exclusively in Middle Eastern populations. A similar syndrome with the additional features of osteosclerosis and recurrent bacterial infections has been classified as autosomal recessive Kenny-Caffey syndrome (AR-KCS; OMIM 244460). Both traits have previously been mapped to chromosome 1q43-44 (refs 5,6) and, despite the observed clinical variability, share an ancestral haplotype, suggesting a common founder mutation. We describe refinement of the critical region to an interval of roughly 230 kb and identification of deletion and truncation mutations of TBCE in affected individuals. The gene TBCE encodes one of several chaperone proteins required for the proper folding of alpha-tubulin subunits and the formation of alpha-beta-tubulin heterodimers. Analysis of diseased fibroblasts and lymphoblastoid cells showed lower microtubule density at the microtubule-organizing center (MTOC) and perturbed microtubule polarity in diseased cells. Immunofluorescence and ultrastructural studies showed disturbances in subcellular organelles that require microtubules for membrane trafficking, such as the Golgi and late endosomal compartments. These findings demonstrate that HRD and AR-KCS are chaperone diseases caused by a genetic defect in the tubulin assembly pathway, and establish a potential connection between tubulin physiology and the development of the parathyroid. 相似文献
903.
Broderick P Chubb D Johnson DC Weinhold N Försti A Lloyd A Olver B Ma YP Dobbins SE Walker BA Davies FE Gregory WA Child JA Ross FM Jackson GH Neben K Jauch A Hoffmann P Mühleisen TW Nöthen MM Moebus S Tomlinson IP Goldschmidt H Hemminki K Morgan GJ Houlston RS 《Nature genetics》2012,44(1):58-61
To identify risk variants for multiple myeloma, we conducted a genome-wide association study of 1,675 individuals with multiple myeloma and 5,903 control subjects. We identified risk loci for multiple myeloma at 3p22.1 (rs1052501 in ULK4; odds ratio (OR) = 1.32; P = 7.47 × 10(-9)) and 7p15.3 (rs4487645, OR = 1.38; P = 3.33 × 10(-15)). In addition, we observed a promising association at 2p23.3 (rs6746082, OR = 1.29; P = 1.22 × 10(-7)). Our study identifies new genomic regions associated with multiple myeloma risk that may lead to new etiological insights. 相似文献
904.