5S RNA Regulation and Ribosome Biogenesis

本研究旨在研究核糖体生物发生中的5S RNA的调控。在高等真核生物中，5S RNA是一种小的120NTS RNA，虽然是核糖体的重要组成部分，但对其定位和功能仍知之甚少。在体细胞中，5S RNA是在细胞核中合成的，并定位于核仁，在那里它被并入新生的更大的核糖体亚单位。在卵母细胞中，5S RNA的大量合成提前了数周，rRNA和r蛋白的合成被激活，核糖体生物发生的开始。因此，这种自然发生的核糖体成分合成的同步性为我们提供了一个独特的机会来研究非洲爪哇卵子发生过程中5S RNA靶向核仁的各个步骤和调控以及5S RNA掺入的要求如何添加到新生的大核糖体亚基中。另一个目的是建立将5S核糖核酸输送到细胞质、储存在那里，然后再运输回细胞核的机制(S)，特别是进入核仁。在更大的背景下，卵母细胞系统将有助于我们理解核蛋白如何与特定的RNA分子相互作用，以及RNPs进出细胞核的运输需要什么。卵母细胞的研究可能会扩大我们对体细胞5S RNA是如何靶向并结合到新生的核糖体中形成核仁的理解，这个过程可能完全发生在体细胞核中。

The research is directed toward studying the regulation of 5S RNA, which is one component of ribosome biogenesis. In higher eukaryotes, 5S RNA is small 120 nts RNA which, although an essential component of ribosomes, is still only partially understood in its ribosome location and function. In somatic cells 5S RNA is synthesized in the nucleus, and targeted to the nucleolus where it is incorporated into nascent larger ribosomal subunits. In oocytes, the synthesis of a large amount of 5S RNA precedes by several weeks, the activation of rRNA and r protein synthesis and the beginning of ribosome biogenesis. Therefore, this naturally occurring a synchrony in the on set of synthesis of ribosome components affords us a unique opportunity to study the various step sand the regulation involved in the targeting of 5S RNA to the nucleolus and the requirements for 5S RNA incorporation how 5S RNA is added to the nascent large ribosomal subunit during oogenesis in Xenopus laevis. A further aim is to establish the mechanism(s) for ferrying the 5S RNA out to the cytoplasm, keeping it stored there, and then transporting it back into the nucleus, specifically into the nucleolus. In a larger context, the oocyte system will facilitate our understanding of how nuclear proteins interact with specific RNA molecules, and what is required for transport of RNPs in and out of the nucleus. The oocyte studies will likely amplify our understanding of how somatic cell 5S RNAis targeted to and incorporated into nascent ribosomes forming with in the nucleolus, a process which probably occurs entirely with in the somatic cell nucleus.