Davis I, Ish-Horowicz D
ICRF Developmental Biology Unit, Zoology Department, Oxford, England.
Cell. 1991 Nov 29;67(5):927-40. doi: 10.1016/0092-8674(91)90366-7.
The peripheral cytoplasm (periplasm) of the Drosophila blastoderm embryo is subdivided into apical and basal compartments by a layer of nuclei. We have demonstrated three classes of periplasmic transcript localization: apical, basal, and unlocalized (apical and basal), each of which depends on 3' sequences. We define 3' apical localization signals within the even-skipped, fushi tarazu, and hairy pair-rule segmentation genes and the alpha 1-tubulin and bicoid genes. 3' human alpha-globin sequences direct transcripts basally. Transcript destination depends on transcript structure, not on transcript stability or chromosomal location. Apical transcripts direct apical compartmentalization of cytoplasmic protein. We propose that apical localization of pair-rule transcripts restricts lateral protein diffusion, thereby allowing pair-rule proteins to define sharp boundaries and precise spatial domains.
果蝇胚盘胚的外周细胞质（周质）被一层细胞核分为顶端和基部两个区室。我们已经证明了三类周质转录本定位：顶端定位、基部定位和非定位（顶端和基部），每一类都依赖于3'序列。我们在偶数缺失、分节基因、α1 -微管蛋白和双胸基因中定义了3'顶端定位信号。3'人α-珠蛋白序列指导转录本向基部定位。转录本的定位取决于转录本结构，而不是转录本稳定性或染色体位置。顶端转录本指导细胞质蛋白的顶端区室化。我们提出，分节基因转录本的顶端定位限制了侧向蛋白质扩散，从而使分节基因蛋白能够定义清晰的边界和精确的空间域。
