A POLYPEPTIDE DOMAIN THAT SPECIFIES MIGRATION OF NUCLEOPLASMIN INTO THE NUCLEUS
A POLYPEPTIDE DOMAIN THAT SPECIFIES MIGRATION OF NUCLEOPLASMIN INTO THE NUCLEUS
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DOI：
10.1016/0092-8674(82)90242-2
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发表时间：
1982-01-01
期刊：
影响因子：
64.5
通讯作者：
LASKEY, RA
中科院分区：
文献类型：
--
作者：
DINGWALL, C;SHARNICK, SV;LASKEY, RA
核纤溶蛋白是非洲爪蟾卵母细胞细胞核中含量最多的蛋白。它被注入卵母细胞细胞质后迅速进入细胞核。核纤溶蛋白五聚体的部分蛋白水解揭示了每个亚基内的2个结构域：一个相对暴露的尾部和一个受保护的核心。当从五聚体中去除所有尾部时，剩余的核心仍然是五聚体。这种五聚体核不能进入细胞核，稳定地留在细胞质中。附着在五聚体上的单个尾部区域足以将其运送到细胞核中。细胞核内的积累速率，而不是最终的程度，取决于每个五聚体的尾部数量。分离的（单体）尾部在卵母细胞核中迅速积累，表明尾部结构足以选择性积累。五聚体核在整个细胞核中扩散，但在微注入细胞核时被保留下来，这表明尾巴是进入细胞核所必需的，而不是留在细胞核内。还描述了一种纯化核纤溶酶的改进方法。
Nucleoplasmin is the most abundant protein of the nucleus of Xenopus laevis oocytes. It rapidly enters the nucleus after being injected into oocyte cytoplasm. Partial proteolysis of the nucleoplasmin pentamer reveals 2 structural domains within each subunit: a relatively exposed tail and a protected core. when all the tails were removed from the pentamer the residual core remains pentameric. This pentameric core fails to enter the nucleus, remaining stably in the cytoplasm. A single tail region attached to the pentamer is sufficient to transport it into the nucleus. The rate of accumulation in the nucleus, but not its final extent, depends on the number of tails per pentamer. The detached (monomeric) tails rapidly accumulate in the oocyte nucleus, indicating that the tail structure is sufficient for selective accumulation. Pentameric cores diffuse throughout the nucleus but are retained when microinjected into the nucleus, indicating that the tail is necessary for entry but not for retention within the nucleus. An improved method for purification of nucleoplasmin is also described.