Bullock S L, Ish-Horowicz D
Developmental Genetics Laboratory, Imperial Cancer Research Fund, London, UK.
Nature. 2001 Dec 6;414(6864):611-6. doi: 10.1038/414611a.
Localization of cytoplasmic messenger RNA transcripts is widely used to target proteins within cells. For many transcripts, localization depends on cis-acting elements within the transcripts and on microtubule-based motors; however, little is known about other components of the transport machinery or how these components recognize specific RNA cargoes. Here, we show that in Drosophila the same machinery and RNA signals drive specific accumulation of maternal RNAs in the early oocyte and apical transcript localization in blastoderm embryos. We demonstrate in vivo that Egalitarian (Egl) and Bicaudal D (BicD), maternal proteins required for oocyte determination, are selectively recruited by, and co-transported with, localizing transcripts in blastoderm embryos, and that interfering with the activities of Egl and BicD blocks apical localization. We propose that Egl and BicD are core components of a selective dynein motor complex that drives transcript localization in a variety of tissues.
细胞质信使核糖核酸转录本的定位被广泛用于在细胞内靶向蛋白质。对于许多转录本而言，定位取决于转录本内的顺式作用元件以及基于微管的马达蛋白；然而，对于运输机制的其他组成部分，或者这些组成部分如何识别特定的RNA货物，我们却知之甚少。在这里，我们表明，在果蝇中，相同的机制和RNA信号驱动早期卵母细胞中母体RNA的特异性积累以及囊胚期胚胎中顶端转录本的定位。我们在体内证明，卵母细胞决定所需的母体蛋白平等主义者（Egl）和双尾D（BicD），在囊胚期胚胎中被定位转录本选择性招募并与其共同运输，并且干扰Egl和BicD的活性会阻止顶端定位。我们提出，Egl和BicD是一种选择性动力蛋白复合体的核心组成部分，该复合体驱动转录本在多种组织中的定位。
