Cis- acting sequences responsible for anterior localization of bicoid mRNA in Drosophila embryos
Cis- acting sequences responsible for anterior localization of bicoid mRNA in Drosophila embryos
复制标题
果蝇胚胎中负责 bicoid mRNA 前部定位的顺式作用序列
作者：
P. Macdonald;G. Struhl
黑腹果蝇的前体模式在很大程度上是由bicoid（bcd）基因的蛋白产物指定的，bicoid基因作为一个分级的形态原，其表达峰值在胚胎的前极1 -5。梯度的形成依赖于bcd信使RNA在卵子发生过程中在卵细胞前极的预先定位6，7。在这里，我们表明，床mRNA的离散部分是必要的前本地化的bcd转录，并足以引起本地化的异源转录。负责定位的序列似乎跨越bcd mRNA的3'非翻译部分中约625个碱基对的间隔，并包括能够形成广泛二级结构的区域。bcd的转录物主要在滋养细胞中合成，然后通过前极的连接运输到卵母细胞中。我们的研究结果支持bcd转录本在进入卵母细胞前尖时被选择性识别和捕获的假设2，并表明这一定位过程是由卵母细胞胞质中锚定的序列特异性受体介导的。
The anterior body pattern of Drosophila melanogaster is specified in large part by the protein product of the bicoid (bcd) gene which functions as a graded morphogen with its peak of expression at the anterior pole of the embryo1–5. Formation of the gradient is dependent on prior localization of bcd messenger RNA at the anterior pole of the egg cell during oogenesis6,7. Here we demonstrate that a discrete portion of the bed mRNA is necessary for anterior localization of the bcd transcript and is sufficient to cause localization of heterologous transcripts. The sequences responsible for localization appear to span an interval of about 625 base pairs in the 3' untranslated portion of the bcd mRNA and to include regions capable of forming extensive secondary structure. Transcripts from bcd are synthesized predominantly, if not exclusively, in the nurse cells and then transported to the oocyte by connections at the prospective anterior pole6,7. Our findings support the proposal2 that bcd transcripts are selectively recognized and trapped as they enter the anterior tip of the oocyte, and suggest that this localization process is mediated by anchored sequence-specific receptors in the oocyte cytoplasm.
DOI：
10.1073/pnas.83.24.9373
发表时间：
1986-12-01
影响因子：
11.1
作者：
FREIER, SM;KIERZEK, R;TURNER, DH
通讯作者：
TURNER, DH