The karyopherin Kap95 regulates nuclear pore complex assembly into intact nuclear envelopes in vivo.
The karyopherin Kap95 regulates nuclear pore complex assembly into intact nuclear envelopes in vivo.
复制标题
核转运蛋白 Kap95 在体内调节核孔复合物组装成完整的核膜。
DOI：
10.1091/mbc.e06-06-0525
复制
发表时间：
2007
影响因子：
3.3
通讯作者：
Wente,SusanR
中科院分区：
文献类型：
--
作者：
Ryan,KathrynJ;Zhou,Yingna;Wente,SusanR
Nuclear pore complex (NPC) assembly in interphase cells requires that new NPCs insert into an intact nuclear envelope (NE). Our previous work identified the Ran GTPase as an essential component in this process. We proposed that Ran is required for targeting assembly factors to the cytoplasmic NE face via a novel, vesicular intermediate. Although the molecular target was not identified, Ran is known to function by modulating protein interactions for karyopherin (Kap) β family members. Here we characterize loss-of-functionSaccharomyces cerevisiaemutants inKAP95with blocks in NPC assembly. Similar to defects in Ran cycle mutants, nuclear pore proteins are no longer localized properly to the NE inkap95mutants. Also like Ran cycle mutants, thekap95-E126Kmutant displayed enhanced lethality withnic96andnup170mutants. Thus, Kap95 and Ran are likely functioning at the same stage in assembly. However, although Ran cycle mutants accumulate small cytoplasmic vesicles, cells depleted of Kap95 accumulated long stretches of cytoplasmic membranes and had highly distorted NEs. We conclude that Kap95 serves as a key regulator of NPC assembly into intact NEs. Furthermore, both Kap95 and Ran may provide spatial cues necessary for targeting of vesicular intermediates in de novo NPC assembly.
