VEGETALLY LOCALIZED TRANSCRIPTS

描述（改编自申请人摘要）：这是一份提案 研究一个新的转录本家族的细胞定位。博士 埃特金的实验室克隆了一个基因家族， 来自非洲爪蟾的散布重复转录物（xlsirts）， 热带爪蟾（Xtsirts）。 序列被组织为串联重复序列 由79-81个核苷酸重复组成的序列，所述重复从3到10个核苷酸重复， 在不同的克隆体中重复了13次。 没有开放的阅读框架， 每个克隆的重复序列的侧翼是不同的独特序列。 使用 重复序列探针原位杂交分析 在第1和第2阶段卵母细胞的线粒体云中检测到， 转移到植物皮质区 关于xlsirt 转录本是动物-植物极性的最早指标之一。 假设是它们可能作为一个结构组成部分， 植物皮层，并可能负责随后的定位 转录本，如xcat 2或vg 1在植物皮层。此外， 该区域的定位可能影响生殖细胞 影响背腹轴的皮层旋转 阵 目的是：（1）检测细胞骨架元件的作用 在xlsirt转录本的定位和锚定中;（2）分析 顺式作用元件在xlsirts定位中的作用;（3） 为了分析xlsirts在其他RNA定位中的作用， 作为卵母细胞中的xcat 2、xcat 3和vg 1，并确定它们的功能 在发育过程中;和（4）从其他的克隆XLSIRT样序列 生物，如果蝇和小鼠，并检查定位 在异源系统中的XLSIRTS。

DESCRIPTION (Adapted from the applicant's abstract): This is a proposal to study the cellular localization of a novel family of transcripts. Dr. Etkin's laboratory has cloned a family of genes that code for interspersed repeat transcripts from Xenopus laevis (xlsirts) and Xenopus tropicalis (xtsirts). Sirts are organized as tandem repeat sequences consisting of 79-81 nt repeats that are reiterated from 3 to 13 times in different clones. There are no open reading frames and in each clone the repeats are flanked by different unique sequences. Using in situ hybridization analysis with the repeat sequence probe the xlsirts were detected in the mitochondrial cloud of stage 1 and 2 oocytes after which they translocate to the vegetal cortical egion. The xlsirt transcripts are one of the earliest indices of animal-vegetal polarity. The hypothesis is that they may function as a structural component of the vegetal cortex and may be responsible for the subsequent localization of transcripts such as xcat2 or vg1 in the vegetal cortex.In addition, their localization in this region may influence processes such as germ cell formation or the cotical rotation which influences dorsal-ventral axis formation. The aims are: (1) to test the role of cytoskeletal elements in the localization and anchoring of xlsirt transcripts; (2) to analyze the role of the cis-acting elements in the localization of xlsirts; (3) to analyze the role of xlsirts in the localization of other RNAs such as xcat2, xcat3, and vg1 in oocytes and to determine their function during development; and (4) to clone xlsirt-like sequences from other organisms such as Drosophila and mouse and to examine the localization of xlsirts in a heterologous system.