STRUCTURE AND FUNCTION OF NUCLEAR RNP PARTICLES

信使RNA（mRNA）是在真核细胞的细胞核中形成的， 初级RNA聚合酶II的广泛转录后加工 成绩单 这些转录物被称为异质核RNA （hnRNA），它们在整个过程中与蛋白质相关， 都在细胞核里 蛋白质的总称 hnRNA，并且其不是其它种类的RNP的稳定组分 snRNP等复合物是hnRNP蛋白。 hnRNP蛋白是一种 RNA结合蛋白和hnRNA在细胞核中的加工 hnRNA-蛋白质（hnRNP）复合物。 hnRNP的意义 蛋白质的另一个特点是它们影响hnRNA的结构，因此 它们的命运和加工成mRNA。 HnRNP蛋白也可能发挥作用 在hnRNP复合物与其他核 结构，在mRNA的核质运输，他们可能有 与hnRNA代谢相关的生化活性。 此外该 hnRNP蛋白是细胞核中最丰富的蛋白质之一， 生长的脊椎动物细胞和hnRNP复合物因此也是感兴趣的 因为它们是主要的核结构。 我们的目标是了解 详细说明基因通路的转录后部分 表达式在单元格中运行。 为此，我们研究了它的结构， hnRNP和细胞质mRNA结合的功能和定位 （mRNP）蛋白和RNP复合物。 在这些方面取得了很大进展， 在过去的几年里，但仍然有很多 重要性还有待学习。 的重点 在这项拨款申请中提出的研究是表征 hnRNP蛋白，包括它们的序列、结构、RNA结合 活性，蛋白质-蛋白质相互作用，组装成复合物， 生物化学活性和mRNA生物合成中的功能。

Messenger RNAs (mRNAs) are formed in the nuclei of eukaryotic cells by extensive post-transcriptional processing of primary RNA polymerase II transcripts. These transcripts are termed heterogeneous nuclear RNAs (hnRNAs) and they are associated with proteins throughout the time they are in the nucleus. The collective term for the proteins that bind hnRNAs, and which are not stable components of other classes of RNP complexes such as snRNPs, is hnRNP proteins. The hnRNP proteins are avid RNA-binding proteins and the processing of hnRNA in the nucleus takes place in hnRNA-protein (hnRNP) complexes. The significance of hnRNP proteins is that they influence the structure of hnRNAs and therefore their fate and processing into mRNAs. HnRNP proteins may also play crucial roles in the interaction of hnRNP complexes with other nuclear structures, in nucleo-cytoplasmic transport of mRNA, and they may have biochemical activity relevant to hnRNA metabolism. In addition, the hnRNP proteins are among the most abundant proteins in the nucleus in growing vertebrate cells, and hnRNP complexes are thus also of interest because they are major nuclear structures. Our goal is to understand in detail how the post-transcriptional portion of the pathway of gene expression operates in the cell. To do so we investigate the structure, function, and localization of the hnRNP and cytoplasmic mRNA-binding (mRNP) proteins and RNP complexes. Much progress has been made in these areas over the past several years but there is still a great deal of fundamental importance that remains to be learned. The focus of the research proposed in this grant application is the characterization of the hnRNP proteins, including their sequence, structure, RNA-binding activity, protein-protein interactions, assembly into complexes, biochemical activities, and function in mRNA biogenesis.