The fission yeast Nup107-120 complex functionally interacts with the small GTPase Ran/Spi1 and is required for mRNA export, nuclear pore distribution, and proper cell division
The fission yeast Nup107-120 complex functionally interacts with the small GTPase Ran/Spi1 and is required for mRNA export, nuclear pore distribution, and proper cell division
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DOI：
10.1128/mcb.24.14.6379-6392.2004
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发表时间：
2004-07-01
影响因子：
5.3
通讯作者：
Doye, V
中科院分区：
文献类型：
--
作者：
Baï, SW;Rouquette, J;Doye, V
我们已经表征了粟酒裂殖酵母开放阅读框架，其编码进化上保守的酿酒酵母Nup 84脊椎动物Nup 107 -160核孔亚复合物的成分的潜在直系同源物，即Nup 133 a、Nup 133 b、Nup 120、Nup 107、Nup 85和Seh 1。尽管序列保守性较弱，但体内分析表明，这些S。粟酒蛋白定位于核膜。生物化学数据证实了这些核孔蛋白在保守复合物中的组织。虽然对S.酿酒酵母和S.粟酒裂殖酵母缺失突变体揭示了不同的活力表型，功能研究表明，这种复合物参与核孔分布和mRNA输出在这些高度分化的酵母之间是保守的。出乎意料的是，一些S。粟酒裂殖酵母突变体在限制性温度下显示细胞分裂缺陷（异常的隔膜和有丝分裂纺锤体以及染色体错误分离），这让人想起在几个S.粟酒裂殖酵母GT3 Ran（Ran（Sp））/Spi 1循环突变体。此外，nup 120的缺失适度改变了Ran（Sp）/Spi 1的核定位，而非功能性Ran（Sp）/Spi 1-GFP等位基因的过表达在Deltanup 120和Deltanup 133 b突变株中具有特异性毒性，表明S. pombe Nup 107 -120复合物和Ran（Sp）/Spi 1途径的蛋白质。
We have characterized Schizosaccharomyces pombe open reading frames encoding potential orthologues of constituents of the evolutionarily conserved Saccharomyces cerevisiae Nup84 vertebrate Nup107-160 nuclear pore subcomplex, namely Nup133a, Nup133b, Nup120, Nup107, Nup85, and Seh1. In spite of rather weak sequence conservation, in vivo analyses demonstrated that these S. pombe proteins are localized at the nuclear envelope. Biochemical data confirmed the organization of these nucleoporins within conserved complexes. Although examination of the S. cerevisiae and S. pombe deletion mutants revealed different viability phenotypes, functional studies indicated that the involvement of this complex in nuclear pore distribution and mRNA export has been conserved between these highly divergent yeasts. Unexpectedly, microscopic analyses of some of the S. pombe mutants revealed cell division defects at the restrictive temperature (abnormal septa and mitotic spindles and chromosome missegregation) that were reminiscent of defects occurring in several S. pombe GTPase Ran (Ran(Sp))/Spi1 cycle mutants. Furthermore, deletion of nup120 moderately altered the nuclear location of Ran(Sp)/Spi1, whereas overexpression of a nonfunctional Ran(Sp)/Spi1-GFP allele was specifically toxic in the Deltanup120 and Deltanup133b mutant strains, indicating a functional and genetic link between constituents of the S. pombe Nup107-120 complex and of the Ran(Sp)/Spi1 pathway.