Asymmetric segregation of PIE-1 in C-elegans is mediated by two complementary mechanisms that act through separate PIE-1 protein domains
Asymmetric segregation of PIE-1 in C-elegans is mediated by two complementary mechanisms that act through separate PIE-1 protein domains
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DOI：
10.1016/s1097-2765(00)00043-5
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发表时间：
2000-08-01
期刊：
影响因子：
16
通讯作者：
Seydoux, G
中科院分区：
文献类型：
--
作者：
Reese, KJ;Dunn, MA;Seydoux, G
CCCH指蛋白PIE-I是在早期胚胎中与生殖谱系分离的生殖细胞命运的调节剂。在每次不对称分裂中，PIE-1优先由生殖系子代遗传，并被排除在体细胞子代之外。我们发现，这种不对称性是由两个互补的机制在蛋白质水平上进行调节。第一个作用于细胞分裂前，在细胞质中富集PIE-1，用于生殖系子代。第二个在细胞分裂后起作用，以消除留在体细胞子细胞中的任何PIE-1。后一种机制依赖于PIE-1的第一CCCH指（ZF 1），其靶向PIE-1在体细胞卵裂球中降解。另外两个生殖系蛋白质，POS-1和MEX-1中的ZF 1也在体细胞卵裂球中降解，这表明局部降解也作用于这些蛋白质以将它们从体细胞谱系中排除。
The CCCH finger protein PIE-I is a regulator of germ cell fate that segregates with the germ lineage in early embryos. At each asymmetric division, PIE-1 is inherited preferentially by the germline daughter and is excluded from the somatic daughter. We show that this asymmetry is regulated at the protein level by two complementary mechanisms. The first acts before cell division to enrich PIE-1 in the cytoplasm destined for the germline daughter. The second acts after cell division to eliminate any PIE-1 left in the somatic daughter. The latter mechanism depends on PIE-1's first CCCH finger (ZF1), which targets PIE-1 for degradation in somatic blastomeres. ZF1s in two other germline proteins, POS-1 and MEX-1,are also degraded in somatic blastomeres, suggesting that localized degradation also acts on these proteins to exclude them from somatic lineages.