The Regulation of RNA Transport and Localization in Drosophila

这项研究的总体目标是确定核糖核酸转运到果蝇卵母细胞中的机制(S)以及在果蝇卵母细胞中的定位，并将这些过程与成熟卵和早期胚胎背腹模式的建立联系起来。本研究以果蝇背腹花纹基因‘fs(1)K10(K10)’为研究对象。在卵子发生的早期和中期，‘K10’RNA在卵巢哺育细胞中合成，并通过细胞质桥梁选择性地运输到卵母细胞中。其他几种在卵子和胚胎模式形成中起关键作用的果蝇RNA，包括‘Oskar’和‘bioid’，也在哺育细胞中合成并选择性地运输到卵母细胞中。越来越多的证据表明，‘K10’、‘Oskar’和‘Bigid’RNA的转运发生在微管束上，因此在机制上类似于高等生物中RNA和细胞器的运输/定位。拟议的研究试图确定和表征‘K10’RNA运输的顺式和反式调节因子。还将对‘K10’蛋白的功能进行研究。PI之所以对此感兴趣，是因为观察到‘K10’是‘Gurken’RNA在卵母细胞内定位所必需的，它编码一个类似于TGFAlpha的信号分子，是卵母细胞邻近体细胞毛囊细胞不对称分化所必需的。这些研究代表了一种解决RNA定位/运输问题的分子、遗传和生化方法，并利用了突变、种系转化、蛋白质-核酸结合、原位杂交和免疫细胞化学技术。

The overall goal of the proposed research is to determine the mechanism(s) of RNA transport into, and localization within, the Drosophila oocyte and to relate such processes to the establishment of dorsoventral pattern in the mature egg and early embryo. This research is focused on the Drosophila dorsoventral patterning gene 'fs(1)K10(K10)'. 'K10' RNA is synthesized in ovarian nurse cells and selectively transported via cytoplasmic bridges into the oocyte during early to middle stages of oogenesis. Several other Drosophila RNAs that play critical roles in egg and embryonic pattern fromation, including 'oskar' and 'bicoid', are also synthesized in nurse cells and selectively transported into the oocyte. There is growing evidence that 'K10', 'oskar' and 'bicoid' RNA transport occurs along microtubule tracts and therefore is similar in mechanism to the transport/localization of RNA and organelles in higher organisms. The proposed studies seek to identify and characterize the cis- and trans-acting regulators of 'K10' RNA transport. An investigation of 'K10' protein function will also be carried out. The PI's interest in this stems from the observation that 'K10' is required for the localization within the oocyte of 'gurken' RNA, which encodes a TGFalpha-like signaling molecule required for the asymmetric differentiation of the oocyte's neighboring somatic follicle cells. The proposed studies represent a molecular, genetic, and biochemical approach to the problem of RNA localization/transport and utilize mutagenesis, germ- line transformation, protein-nucleic acid binding, in situ hybridization, and immunocytochemical techniques.