The Caenorhabditis elegans par-5 gene encodes a 14-3-3 protein required for cellular asymmetry in the early embryo
The Caenorhabditis elegans par-5 gene encodes a 14-3-3 protein required for cellular asymmetry in the early embryo
复制标题
DOI：
10.1006/dbio.2001.0489
复制
发表时间：
2002-01-01
影响因子：
2.7
通讯作者：
Kemphues, KJ
中科院分区：
文献类型：
--
作者：
Morton, DG;Shakes, DC;Kemphues, KJ
秀丽隐杆线虫胚胎前后极性的建立需要母系表达par基因的活性。我们报告了一个新的par基因，par-5的鉴定和分析。我们发现，在第一次胚胎细胞分裂、正常的假分裂、双细胞阶段正常的分裂纺锤体方向以及第一次和随后的细胞周期中P颗粒和MEX-5的定位中，par-5是异步和不对称所必需的。此外，PAR-1和PAR-2以及PAR-3、PAR-6和PKC-3在大脑皮层的不对称定位需要第一个细胞周期中的par-5活性。当PAR-5因突变或RNA干扰而减少时，这些蛋白质在单细胞胚胎的皮层周围扩散并部分重叠。我们通过对par5突变体的序列分析和RNA干扰表明，par5基因与ftt-1基因相同，并编码14-3-3蛋白。PAR-5 14-3-3蛋白存在于生殖腺、卵母细胞和早期胚胎中，但不是不对称分布。我们的分析表明，par-5 14-3-3基因在导致秀丽隐杆线虫合子极化的早期事件中起着关键作用。(C) 2001 Elsevier Science。
The establishment of anterior-posterior polarity in the Caenorhabditis elegans embryo requires the activity of the maternally expressed par genes. We report the identification and analysis of a new par gene, par-5. We show that par-5 is required for asynchrony and asymmetry in the first embryonic cell divisions, normal pseudocleavage, normal cleavage spindle orientation at the two-cell stage, and localization of P granules and MEX-5 during the first and subsequent cell cycles. Furthermore, par-5 activity is required in the first cell cycle for the asymmetric cortical localization of PAR-1 and PAR-2 to the posterior, and PAR-3, PAR-6, and PKC-3 to the anterior. When PAR-5 is reduced by mutation or by RNA interference, these proteins spread around the cortex of the one-cell embryo and partially overlap. We have shown by sequence analysis of par-5 mutants and by RNA interference that the par-5 gene is the same as the ftt-1 gene, and encodes a 14-3-3 protein. The PAR-5 14-3-3 protein is present in,gonads, oocytes, and early embryos, but is not asymmetrically distributed. Our analysis indicates that the par-5 14-3-3 gene plays a crucial role in the early events leading to polarization of the C. elegans zygote. (C) 2001 Elsevier Science.