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291.
292.
Xin Zhu Yinwen Liang Feng Gao Junmin Pan 《Cellular and molecular life sciences : CMLS》2017,74(18):3425-3437
Intraflagellar transport (IFT) is required for ciliogenesis by ferrying ciliary components using IFT complexes as cargo adaptors. IFT54 is a component of the IFT-B complex and is also associated with cytoplasmic microtubules (MTs). Loss of IFT54 impairs cilia assembly as well as cytoplasmic MT dynamics. The N-terminal calponin homology (CH) domain of IFT54 interacts with tubulins/MTs and has been proposed to transport tubulin during ciliogenesis, whereas the C-terminal coiled-coil (CC) domain binds IFT20. However, the precise function of these domains in vivo is not well understood. We showed that in Chlamydomonas, loss of IFT54 completely blocks ciliogenesis but does not affect spindle formation and proper cell cycle progression, even though IFT54 interacts with mitotic MTs. Interestingly, IFT54 lacking the CH domain allows proper flagellar assembly. The CH domain is required for the association of IFT54 with the axoneme but not with mitotic MTs, and also regulates the flagellar import of IFT54 but not IFT81 and IFT46. The C-terminal CC domain is essential for IFT54 to bind IFT20, and for its recruitment to the basal body and incorporation into IFT complexes. Complete loss of IFT54 or the CC domain destabilizes IFT20. ift54 mutant cells expressing the CC domain alone rescue the stability of IFT20 and form stunted flagella with accumulation of both IFT-A component IFT43 and IFT-B component IFT46, indicating that IFT54 also functions in IFT turn-around at the flagellar tip. 相似文献
293.
294.
Lin Z Bei JX Shen M Li Q Liao Z Zhang Y Lv Q Wei Q Low HQ Guo YM Cao S Yang M Hu Z Xu M Wang X Wei Y Li L Li C Li T Huang J Pan Y Jin O Wu Y Wu J Guo Z He P Hu S Wu H Song H Zhan F Liu S Gao G Liu Z Li Y Xiao C Li J Ye Z He W Liu D Shen L Huang A Wu H Tao Y Pan X Yu B Tai ES Zeng YX Ren EC Shen Y Liu J Gu J 《Nature genetics》2012,44(1):73-77
To identify susceptibility loci for ankylosing spondylitis, we performed a two-stage genome-wide association study in Han Chinese. In the discovery stage, we analyzed 1,356,350 autosomal SNPs in 1,837 individuals with ankylosing spondylitis and 4,231 controls; in the validation stage, we analyzed 30 suggestive SNPs in an additional 2,100 affected individuals and 3,496 controls. We identified two new susceptibility loci between EDIL3 and HAPLN1 at 5q14.3 (rs4552569; P = 8.77 × 10(-10)) and within ANO6 at 12q12 (rs17095830; P = 1.63 × 10(-8)). We also confirmed previously reported associations in Europeans within the major histocompatibility complex (MHC) region (top SNP, rs13202464; P < 5 × 10(-324)) and at 2p15 (rs10865331; P = 1.98 × 10(-8)). We show that rs13202464 within the MHC region mainly represents the risk effect of HLA-B*27 variants (including HLA-B*2704, HLA-B*2705 and HLA-B*2715) in Chinese. The two newly discovered loci implicate genes related to bone formation and cartilage development, suggesting their potential involvement in the etiology of ankylosing spondylitis. 相似文献
295.
Gui Y Guo G Huang Y Hu X Tang A Gao S Wu R Chen C Li X Zhou L He M Li Z Sun X Jia W Chen J Yang S Zhou F Zhao X Wan S Ye R Liang C Liu Z Huang P Liu C Jiang H Wang Y Zheng H Sun L Liu X Jiang Z Feng D Chen J Wu S Zou J Zhang Z Yang R Zhao J Xu C Yin W Guan Z Ye J Zhang H Li J Kristiansen K Nickerson ML Theodorescu D Li Y Zhang X Li S Wang J Yang H Wang J Cai Z 《Nature genetics》2011,43(9):875-878
Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we discovered a variety of genes previously unknown to be mutated in TCC. Notably, we identified genetic aberrations of the chromatin remodeling genes (UTX, MLL-MLL3, CREBBP-EP300, NCOR1, ARID1A and CHD6) in 59% of our 97 subjects with TCC. Of these genes, we showed UTX to be altered substantially more frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer. 相似文献
296.
Pan Q Qiao F Gao C Norman B Optican L Zelenka PS 《Cellular and molecular life sciences : CMLS》2011,68(20):3425-3436
The non-receptor tyrosine kinase Src is a critical regulator of cytoskeletal contraction, cell adhesion, and migration. In
normal cells, Src activity is stringently controlled by Csk-dependent phosphorylation of Src(Y530), and by Cullin-5-dependent
ubiquitinylation, which affects active Src(pY419) exclusively, leading to its degradation by the proteosome. Previous work
has shown that Src activity is also limited by Cdk5, a proline-directed kinase, which has been shown to phosphorylate Src(S75).
Here we show that this phosphorylation promotes the ubiquitin-dependent degradation of Src, thus restricting the availability
of active Src. We demonstrate that Src(S75) phosphorylation occurs in vivo in epithelial cells, and like ubiquitinylation,
is associated only with active Src. Preventing Cdk5-dependent phosphorylation of Src(S75), by site-specific mutation of S75
or by Cdk5 inhibition or suppression, increases Src(Y419) phosphorylation and kinase activity, resulting in Src-dependent
cytoskeletal changes. In transfected cells, ubiquitinylation of Src(S75A) is about 35% that of wild-type Src-V5, and its half-life
is approximately 2.5-fold greater. Cdk5 suppression leads to a comparable decrease in the ubiquitinylation of endogenous Src
and a similar increase in Src stability. Together, these findings demonstrate that Cdk5-dependent phosphorylation of Src(S75)
is a physiologically significant mechanism of regulating intracellular Src activity. 相似文献
297.
试论图书馆联盟在信息网格应用中的作用 总被引:1,自引:0,他引:1
高国丽 《科技情报开发与经济》2006,16(5):6-8
介绍了信息网格和图书馆联盟的涵义,阐述了网格技术应用过程中的问题,探讨了图书馆联盟在信息网格应用中的作用,指出图书馆联盟作为图书馆际合作组织,在信息网格时代应利用信息网格技术推动图书馆际间资源共享,提高图书馆信息服务质量和能力,促进信息网格的信息连通,使其逐渐成熟。 相似文献
298.
高国力 《科技导报(北京)》2006,24(6):63-66
经济技术开发区作为一种特殊类型经济功能区,在我国改革开放和经济发展过程中发挥着重要作用,同时也存在许多突出问题。在新形势下,来自经济全球化国际大背景和全面建设小康社会国内大环境的双重影响,使得经济技术开发区面临着新的机遇和挑战。立足国内外经济社会发展变化趋势,应进一步明确我国经济技术开发区中长期发展方向和定位,并在此基础上提出“十一五”及今后一段时期面临的重点任务。 相似文献
299.
This paper investigates the nonnegative approximate controllability for the one-dimensional degenerate heat equation governed by bilinear control. Both non-controllability and approximate controllability are studied for the system. If the control is restricted to act on a fixed domain, it is not controllable. If the control is allowed to mobile, it is approximately controllable. 相似文献
300.
In this era of big data, data are often collected from multiple sources that have different reliabilities, and there is inevitable conflict with respect to the various information obtained when it relates to the the same object.One important task is to identify the most trustworthy value out of all the conflicting claims, and this is known as truth discovery. Existing truth discovery methods simultaneously identify the most trustworthy information and source reliability degrees and are based on the idea that more reliable sources often provide more trustworthy information,and vice versa. However, there are often semantic constrains defined upon relational database, which can be violated by a single data source. To remove violations, an important task is to repair data to satisfy the constrains,and this is known as data cleaning. The two problems above may coexist, but considering them together can provide some benefits, and to the authors knowledge, this has not yet been the focus of any research. In this paper, therefore, a schema-decomposing based method is proposed to simultaneously discover the truth and to clean the data, with the aim of improving accuracy. Experimental results using real world data sets of notebooks and mobile phones, as well as simulated data sets, demonstrate the effectiveness and efficiency of our proposed method. 相似文献