排序方式: 共有41条查询结果,搜索用时 15 毫秒
21.
22.
Karin A. Mattern Bruno M. Humbel Anton O. Muijsers Luitzen de Jong Roel van Driel 《Journal of cellular biochemistry》1996,62(2):275-289
The nuclear matrix is the structure that persists after removal of chromatin and loosely bound components from the nucleus. It consists of a peripheral lamina-pore complex and an intricate internal fibrogranular structure. Little is known about the molecular structure of this proteinaceous internal network. Our aim is to identify the major proteins of the internal nuclear matrix of HeLa S3 cells. To this end, a cell fraction containing the internal fibrogranular structure was compared with one from which this structure had been selectively dissociated. Protein compositions were quantitatively analyzed after high-resolution two-dimensional gel electrophoresis. We have identified the 21 most abundant polypeptides that are present exclusively in the internal nuclear matrix. Sixteen of these proteins are heterogeneous nuclear ribonucleoprotein (hnRNP) proteins. B23 (numatrin) is another abundant protein of the internal nuclear matrix. Our results show that most of the quantitatively major polypeptides of the internal nuclear matrix are proteins involved in RNA metabolism, including packaging and transport of RNA. © 1996 Wiley-Liss, Inc. 相似文献
23.
24.
This review considers the results of probing the structure of ribonucleoprotein particles of helical plant viruses by tritium planigraphy (TP). This method works by exposing macromolecular targets to a beam of tritium atoms and analyzing the tritium label distribution along the macromolecule length. The TP data combined with theoretical predictions made it possible to propose a structural model of the coat protein for the virions of potato viruses X (the type representative of potexviruses) and A (a potyvirus), which eluded X-ray diffraction analysis so far. TP revealed fine structural differences between the wild-type tobacco mosaic virus (strain U1) and its temperature-sensitive mutant with an altered coat protein and host specificity. The possibilities of using TP for studying the RNA–protein interactions in helical virus particles are discussed. 相似文献
25.
26.
27.
Carissimi C Baccon J Straccia M Chiarella P Maiolica A Sawyer A Rappsilber J Pellizzoni L 《FEBS letters》2005,579(11):2348-2354
A macromolecular complex containing survival of motor neurons (SMN), the spinal muscular atrophy protein, and Gemin2-7 interacts with Sm proteins and snRNAs to carry out the assembly of these components into spliceosomal small nuclear ribonucleoproteins (snRNPs). Here we report the characterization of unr-interacting protein (unrip), a GH-WD protein of unknown function, as a component of the SMN complex that interacts directly with Gemin6 and Gemin7. Unrip also binds a subset of Sm proteins, and unrip-containing SMN complexes are necessary and sufficient to mediate the assembly of spliceosomal snRNPs. These results demonstrate that unrip functions in the pathway of snRNP biogenesis and is a marker of cellular SMN complexes active in snRNP assembly. 相似文献
28.
Prashali Bansal Johannes Madlung Kristina Schaaf Boris Macek Fulvia Bono 《Molecular & cellular proteomics : MCP》2020,19(9):1485-1502
Highlights
- •Label-free and dimethyl labeling MS analysis of 6 RBPs from Drosophila ovaries.
- •Functionally related RBPs show overlapping proteomes.
- •Selective co-purification of splicing factors and translational regulators.
- •Validation of 26 novel interactions by co-immunoprecipitation.
29.
核不均一核糖核蛋白(heterogeneous nuclear ribonucleoproteins, hnRNPs)是一类结合DNA和RNA的核蛋白,并能在核质间穿梭. A/B型hnRNPs(heterogeneous nuclear ribonucleoproteins,hnRNP A/B)是hnRNPs中研究最为清楚的一大类别,生物信息学分析hnRNP A/B可以区分成A和D两个亚群,已鉴定的D亚群主要成员包括hnRNP AB, D和DL. hnRNP A/B的D亚群均含有2个保守的RNA结合结构域(RNA binding domain, RBD)和1个Gly富集区(glycine-rich domain, GRD),成员间的主要区别在于N端和C端的长度和序列不同. D亚群与pre-mRNA和其它蛋白质结合成微粒系统,参与pre-mRNA的加工、稳定、核输出以及翻译过程. 此外,D亚群也能结合单链和双链DNA,参与转录起始和端粒的稳定. 因此,hnRNP A/B的 D亚群在各个阶段影响基因的表达,在神经系统发育、肿瘤的发生发展及衰老过程中发挥着多样性的功能. 相似文献
30.
Hazeki N Tsukamoto T Yazawa I Koyama M Hattori S Someki I Iwatsubo T Nakamura K Goto J Kanazawa I 《Biochemical and biophysical research communications》2002,294(2):429-440
Intranuclear inclusions have been observed in the brains of patients affected with Huntington's disease (HD). Neuro 2A cells that transiently expressed HD exon 1 bearing 74 glutamine repeats linked to the green fluorescent protein (GFP) and the nuclear localization sequence (NLS) contained aggregates in nuclei. The aggregates were purified by fractionation with centrifugation followed by fluorescence-activated cell sorting (FACS). Heat treatment of the aggregate in an SDS sample buffer caused the dense aggregate cores to disappear and generated a basket-like structure composed of fibrils. Biochemical analysis of the aggregates revealed that the HD exon 1-GFP fusion protein was the major component. The heterogeneous nuclear ribonucleoproteins F and H, histones and ubiquitin were found to be associated with the aggregates. Our observations suggest that the N-terminal fragment of huntingtin may organize the skeletal structure of the aggregates and may disturb normal cellular functions by trapping other proteins within the aggregates. 相似文献