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排序方式: 共有746条查询结果,搜索用时 62 毫秒
581.
582.
Microarray technology outgrew the detection of simple intermolecular interactions, as incubation of slides with living cells opened new vistas. Cell-based array technology permits simultaneous detection of several different cell surface molecules, allowing the complex characterization of cells with an amount of information that is hardly assessed by any other technique. Furthermore, binding of cells to printed antibodies or ligands may induce their activation, and consequently the outcome of these interactions, such as phosphorylation, gene expression, secretion of various products; differentiation, proliferation and apoptosis of the cells are also measurable on arrays. Moreover, since cells can be transfected with printed vectors, over- or under-expression of selected genes is also achievable simultaneously, creating a nice tool for assessing the function of a given gene. The enormously high-throughput cell-based microarray technology enables testing the effect of external stimuli on a scale that was earlier unthinkable. This review summarizes the possible applications of cell-based arrays. 相似文献
583.
Quesada V Conde L Villamor N Ordóñez GR Jares P Bassaganyas L Ramsay AJ Beà S Pinyol M Martínez-Trillos A López-Guerra M Colomer D Navarro A Baumann T Aymerich M Rozman M Delgado J Giné E Hernández JM González-Díaz M Puente DA Velasco G Freije JM Tubío JM Royo R Gelpí JL Orozco M Pisano DG Zamora J Vázquez M Valencia A Himmelbauer H Bayés M Heath S Gut M Gut I Estivill X López-Guillermo A Puente XS Campo E López-Otín C 《Nature genetics》2012,44(1):47-52
Here we perform whole-exome sequencing of samples from 105 individuals with chronic lymphocytic leukemia (CLL), the most frequent leukemia in adults in Western countries. We found 1,246 somatic mutations potentially affecting gene function and identified 78 genes with predicted functional alterations in more than one tumor sample. Among these genes, SF3B1, encoding a subunit of the spliceosomal U2 small nuclear ribonucleoprotein (snRNP), is somatically mutated in 9.7% of affected individuals. Further analysis in 279 individuals with CLL showed that SF3B1 mutations were associated with faster disease progression and poor overall survival. This work provides the first comprehensive catalog of somatic mutations in CLL with relevant clinical correlates and defines a large set of new genes that may drive the development of this common form of leukemia. The results reinforce the idea that targeting several well-known genetic pathways, including mRNA splicing, could be useful in the treatment of CLL and other malignancies. 相似文献
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585.
Poulsen LR López-Marqués RL Palmgren MG 《Cellular and molecular life sciences : CMLS》2008,65(20):3119-3125
Our understanding of flippase-mediated lipid translocation and membrane vesiculation, and the involvement of P-type ATPases
in these processes is just beginning to emerge. The results obtained so far demonstrate significant complexity within this
field and point to major tasks for future research. Most importantly, biochemical characterization of P4-ATPases is required in order to clarify whether these transporters indeed are capable of catalyzing transmembrane phospholipid
flipping. The β-subunit of P4-ATPases shows unexpected similarities between the β- and γ-subunits of the Na+/K+-ATPase. It is likely that these proteins provide a similar solution to similar problems, and might have adopted similar structures
to accomplish these tasks. No P4-ATPases have been identified in the endoplasmic reticulum and it remains an intriguing possibility that, in this compartment,
P5A-ATPases are functional homologues of P4-ATPases.
Received 19 June 2008; received after revision 31 July 2008; accepted 15 August 2008 相似文献
586.
587.
International Consortium for Systemic Lupus Erythematosus Genetics 《Nature genetics》2008,40(2):204-210
Systemic lupus erythematosus (SLE) is a common systemic autoimmune disease with complex etiology but strong clustering in families (lambda(S) = approximately 30). We performed a genome-wide association scan using 317,501 SNPs in 720 women of European ancestry with SLE and in 2,337 controls, and we genotyped consistently associated SNPs in two additional independent sample sets totaling 1,846 affected women and 1,825 controls. Aside from the expected strong association between SLE and the HLA region on chromosome 6p21 and the previously confirmed non-HLA locus IRF5 on chromosome 7q32, we found evidence of association with replication (1.1 x 10(-7) < P(overall) < 1.6 x 10(-23); odds ratio = 0.82-1.62) in four regions: 16p11.2 (ITGAM), 11p15.5 (KIAA1542), 3p14.3 (PXK) and 1q25.1 (rs10798269). We also found evidence for association (P < 1 x 10(-5)) at FCGR2A, PTPN22 and STAT4, regions previously associated with SLE and other autoimmune diseases, as well as at > or =9 other loci (P < 2 x 10(-7)). Our results show that numerous genes, some with known immune-related functions, predispose to SLE. 相似文献
588.
Nath SK Han S Kim-Howard X Kelly JA Viswanathan P Gilkeson GS Chen W Zhu C McEver RP Kimberly RP Alarcón-Riquelme ME Vyse TJ Li QZ Wakeland EK Merrill JT James JA Kaufman KM Guthridge JM Harley JB 《Nature genetics》2008,40(2):152-154
We identified and replicated an association between ITGAM (CD11b) at 16p11.2 and risk of systemic lupus erythematosus (SLE) in 3,818 individuals of European descent. The strongest association was at a nonsynonymous SNP, rs1143679 (P = 1.7 x 10(-17), odds ratio = 1.78). We further replicated this association in two independent samples of individuals of African descent (P = 0.0002 and 0.003; overall meta-analysis P = 6.9 x 10(-22)). The genetic association between ITGAM and SLE implicates the alpha(M)beta2-integrin adhesion pathway in disease development. 相似文献
589.
Morphogenesis in skin is governed by discrete sets of differentially expressed microRNAs 总被引:24,自引:0,他引:24
Yi R O'Carroll D Pasolli HA Zhang Z Dietrich FS Tarakhovsky A Fuchs E 《Nature genetics》2006,38(3):356-362
During embryogenesis, multipotent progenitors within the single-layered surface epithelium differentiate to form the epidermis and its appendages. Here, we show that microRNAs (miRNAs) have an essential role in orchestrating these events. We cloned more than 100 miRNAs from skin and show that epidermis and hair follicles differentially express discrete miRNA families. To explore the functional significance of this finding, we conditionally targeted Dicer1 gene ablation in embryonic skin progenitors. Within the first week after loss of miRNA expression, cell fate specification and differentiation were not markedly impaired, and in the interfollicular epidermis, apoptosis was not markedly increased. Notably, however, developing hair germs evaginate rather than invaginate, thereby perturbing the epidermal organization. Here we characterize miRNAs in skin, the existence of which was hitherto unappreciated, and demonstrate their differential expression and importance in the morphogenesis of epithelial tissues within this vital organ. 相似文献
590.
Service S DeYoung J Karayiorgou M Roos JL Pretorious H Bedoya G Ospina J Ruiz-Linares A Macedo A Palha JA Heutink P Aulchenko Y Oostra B van Duijn C Jarvelin MR Varilo T Peddle L Rahman P Piras G Monne M Murray S Galver L Peltonen L Sabatti C Collins A Freimer N 《Nature genetics》2006,38(5):556-560
The genome-wide distribution of linkage disequilibrium (LD) determines the strategy for selecting markers for association studies, but it varies between populations. We assayed LD in large samples (200 individuals) from each of 11 well-described population isolates and an outbred European-derived sample, using SNP markers spaced across chromosome 22. Most isolates show substantially higher levels of LD than the outbred sample and many fewer regions of very low LD (termed 'holes'). Young isolates known to have had relatively few founders show particularly extensive LD with very few holes; these populations offer substantial advantages for genome-wide association mapping. 相似文献