Regulation of slow troponin C gene expression

对遗传信息的解码涉及到从DNA中合成信使RNA，这一过程发生在哺乳动物细胞的细胞核中。离开细胞核后的信使RNA在细胞质中被翻译成蛋白质，这是所有细胞功能所必需的。最近的研究表明，mRNAs被分选到不同的细胞质位置。这一过程被认为是重要的蛋白质在细胞内的不对称分布。蛋白质的亚对称分布是胚胎正常发育的一个非常重要的方面。因此，蛋白质在细胞中错误的位置表达可能是有害的，并可能导致胚胎身体平面的改变。将mRNAs转移到其适当的细胞质位置对于许多多组分细胞结构的组装也是重要的，如肌丝。如果编码肌丝不同蛋白质的mRNAs共定位在不同的细胞质位置，所有蛋白质成分在同一位置表达，将更有效地将它们组装到肌肉结构中。比依赖简单的扩散过程。mRNAs是如何被分类到细胞质中的不同位置仍然不清楚。我们目前正在研究mRNAs是否包含它们自己的邮政编码。我们对编码肌肉蛋白之一肌钙蛋白C的mRNA的研究表明，它有一个邮政编码将其定位在核周位置。我们正在进一步表征这个邮政编码是如何在其位置锚定mRNA的。因此，我们计划鉴定肌钙蛋白C基因的邮政编码结合蛋白，并确定其在肌肉细胞中的功能。我们的工作有望产生新的知识，以提高我们对mRNA运输的重要细胞过程的理解。

Decoding of the genetic information involves the synthesis of messenger RNA(mRNA)from the DNA.This process takes place in the nucleus of mammalian cells.The mRNA after exiting the nucleus is translated in the cytoplasm to produce proteins,which are required for all cellular functions.Recent studies suggests that mRNAs are sorted to different cytoplasmic locations.This process is believed to be important for assymatric distribution of proteins in the cell. Assymatric distribution of proteins  is an  important aspect of proper embryonic development.Therefore, expression of a protein at the wrong place in the cell could be detrimental and may result in the altered body plan of the embryo.Trafficking of mRNAs to its proper cytoplasmic location is also important for the assembly of many multicomponent cellular structures,such as the muscle filaments.If the mRNAs encoding different proteins of the muscle filament are co-localized at a distinct cytoplasmic site,expression of all protein components at the same site, would be more efficient for their assembly into the muscle structure,than relying on the simple diffusion process.How mRNAs are sorted to different locations in the cytoplasm is still not clear.We are currently investgating whether mRNAs contain their own zipcode.Our studies on an mRNA that encodes one of the muscle proteins,the troponin C, showed that it has a zipcode for loclizing it at the perinuclear site.We are further characterizing how this zip code anchors the mRNA at its site. We propose that it binds to a specific zipcode binding protein at the perinuclear cytoplasmic tract.Therefore we plan to identify the troponin C mRNA's zipcode binding protein and determine how it functions in muscle cells. Our work is expected to produce new knowledge to improve our understanding of the important cellular process of mRNA trafficking.