RNA Transport

King9985627RNA定位是一种强大的策略，可用于将蛋白质定位到亚细胞结构域，并在区域内控制蛋白质的合成。在生殖细胞中，RNA靶向对发育具有深远的意义，它可以建立局部浓度的调节蛋白，从而在发育中的胚胎中建立局部命运。选择和运输RNA的细胞机制可能是保守的，即使在完全不同的物种中也是如此。事实上，研究表明，酵母将编码细胞命运决定因素的RNA定位在子芽的远端，这表明这种机制是古老的。最近的证据表明，运输的选择可能是在细胞核中启动的。然而，除了少数例外，参与RNA选择、翻译调控和皮质锚定的相互作用蛋白的身份尚不清楚。了解RNA是如何定位的是细胞生物学和发育生物学的一个中心问题。为了研究RNA定位的机制，King博士分离并鉴定了7个定位于非洲爪哇卵母细胞植物皮质的mRNAs。已确定了两条定位途径，它们在卵子发生期间操作，将RNA靶向植物皮质。根据这七个RNA的特性，金博士提出，早期的途径进化为专门定位生殖细胞决定因素，而后期的途径用于定位参与胚胎发育的RNA。该提案将重点分析作为早期途径的成员和生发颗粒(13、19、23、55)的组成部分的RNA以及代表晚期途径的Vegt RNA。Vegt编码一种转录因子，它在胚胎的三个主要生殖层的模式中起着至关重要的作用。控制基因何时何地表达对于多细胞生物体的发育至关重要。一种策略是将DNA转录成RNA，然后进行本地化。随后，这种RNA转化为蛋白质，开始适当的细胞分化。金斯博士的工作重点是如何利用这一机制在脊椎动物胚胎中建立三个组织层。

King9985627RNA localization is a powerful strategy that can be used to localizeproteins to subcellular domains and to control protein synthesis regionally. Ingerm cells, RNA targeting has profound implications for development, setting up localconcentrations of regulatory proteins that establish regional fates in the developing embryo. The cellular mechanisms that select and transport RNAs are likely to be conserved, even across widely disparate species. In fact, it has been shown that yeast localizes RNA encoding cell-fate determinants to the distal tip of daughter buds, suggesting this mechanism is ancient . Recent evidence suggests that selection for transport may be initiated in the nucleus. However, with few exceptions, the identities of the interacting proteins involved in RNA selection, translational regulation and corticalanchoring are unknown. Understanding how RNAs are localized represents a central problem in both cell and developmental biology.In order to study the mechanism of RNA localization, Dr. King has isolated and characterized seven mRNAs localized to the vegetal cortex of Xenopus oocytes. Two localization pathways were identified that operate during oogenesis to target RNAs to the vegetal cortex. Based on the identities of these seven RNAs, Dr. King has suggested that the early pathway evolved to specifically localize germ cell determinants whereas the late pathway serves to localize RNAs involved in embryonic development. This proposal will focus on analyzing an RNA, that is a member of the early pathway and a component of the germinal granules (13, 19, 23, 55) as well as VegT RNA, a representative of the late pathway. VegT encodes a transcription factor that plays an essential role in patterning the three primary germ layers in the embryo.Controlling when and where genes are expressed is essential for the development of multicellular organisms. One strategy is to transcribe the DNA to RNA which is then localized. Later translation of this RNA into protein begins appropriate cell differentiation. Dr. Kings work will focus on how this mechanism maybe utilized to establish three tissue layers in the vertebrate embryo.