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）。 或前mRNA，在整个过程中与特定的蛋白质相关， 它们在细胞核中。蛋白质的总称 hnRNA及其核加工产物，以及不稳定的 其他类型的RNP复合物如snRNP的组分是hnRNP proteins. hnRNP蛋白是亲和的RNA结合蛋白， hnRNA在核中的加工发生在hnRNA蛋白（hnRNP）中。 配合物hnRNP蛋白的重要性在于它们影响了细胞的增殖。 hnRNA的结构和相互作用及其加工成mRNA。作为 一些hnRNP蛋白穿梭于细胞核和细胞质之间， 也可能在细胞质和细胞核中具有新的功能， mRNA的细胞质转运。主要的hnRNP蛋白是在 因此，细胞核和hnRNP复合物中最丰富的蛋白质也是 因为它们是主要的核结构。 为了 了解基因表达的转录后途径 在细胞中运作，我们研究其结构，功能， hnRNP蛋白的定位。尽管在这方面取得了很大进展， 在过去的几年里，这些领域有很多基本的 重要性有待了解。中提出的研究重点 这项拨款申请是关于进一步的分子表征， 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，生物化学活动和mRNA生物合成中的功能。

Messenger RNAs (mRNAs) are formed in the nuclei of eukaryotic cells by extensive posttranscriptional processing of primary RNA polymerase II transcripts. These transcripts, called heterogeneous nuclear RNAs (hnRNAs) or pre-mRNAs, are associated with specific proteins throughout the time they are in the nucleus. The collective term for the proteins that bind hnRNAs and their nuclear processing products, 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 and interactions of hnRNAs and their processing into mRNAs. As several hnRNP proteins shuttle between the nucleus and the cytoplasm, they may also have novel functions in the cytoplasm as well as in nucleo- cytoplasmic transport of mRNAs. The major hnRNP proteins are among the most abundant proteins in the nucleus and hnRNP complexes are thus also of interest because they are major nuclear structures. In order to understand how the post-transcriptional pathway of gene expression operates in the cell, we investigate the structure, function, and localization of the hnRNP proteins. Though much progress has been made in these areas over the past several years, a great deal of fundamental importance remains to be learned. The focus of the research proposed in this grant application is on the further molecular characterization of the hnRNP proteins, including determination of their sequences, structures, RNA-binding activities, protein-protein interactions, assembly into complexes, biochemical activities, and functions in mRNA biogenesis.