Identification and functional analysis of cytoplasmic factors involved in nuclear protein transport

参与核蛋白转运的细胞质因子的鉴定和功能分析

• 批准号: 05680612
• 负责人: IMAMOTO Naoko
• 金额: $ 1.28万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05680612/
• 关键词: nulclear transport; nuclear location signal; nuclear pore; in vitro transport system; in vitro輸送系; 熱ショックタンパク質

Targeting of karyophilic proteins to nuclear pores is known to require several cytoplasmic factors including the nuclear location signal (NLS) -binding protein. Using a digitonin-permeabilized cell-free transport assay, we have obtained a cytoplasmic fraction containing factors that specifically bind to karyophilic protein and support the nuclear binding step of the transport. Components in this fraction form a stable complex with the karyophile through interaction with NLS.Since this complex shows nuclear pore binding activity prior to nuclear entry in the absence of other cytosolic factors, we call it nuclear pore-targeting complex. It consists of karyophilic protein and four proteins of 54,56,66, and 90kDa. In our reconstitution experiments, a complex with 54 and 90kDa proteins is capable of targeting karyophiles to the nuclear pores.

已知嗜核蛋白质靶向核孔需要几种细胞质因子，包括核定位信号（NLS）结合蛋白。使用毛地黄皂苷透化的无细胞转运试验，我们已经获得了一个细胞质部分含有的因子，特异性结合到亲核蛋白和支持核结合的运输步骤。该组分通过与NLS相互作用与亲核体形成稳定的复合物，由于该复合物在没有其他胞质因子存在的情况下在进入核之前显示出核孔结合活性，我们称其为核孔靶向复合物。它由嗜核蛋白和分子量分别为54、56、66和90kDa的四种蛋白质组成。在我们的重建实验中，具有54和90kDa蛋白质的复合物能够将亲核体靶向到核孔。

项目成果

Nako lmamoto: "A karyophilic protein forms a stable complex with cutoplasmic components prior to nuclear pore binding." J.Biol.Chem.(in press).

Nako Imamoto：“亲核蛋白在核孔结合之前与胞浆成分形成稳定的复合物。”

Naoko Imamoto: "A karyophilic protein forms a stable complex with cytoplasmic components prior to nuclear pore binding." J.Biol.Chem.(in press).

Naoko Imamoto：“亲核蛋白在核孔结合之前与细胞质成分形成稳定的复合物。”

Taro Tachibana: "Loss of RCC1 leads to suppression of nuclear protein import in living cells" J.Biol.Chem.269. 24542-24545 (1994)

Taro Tachibana：“RCC1 的缺失会导致活细胞中核蛋白输入的抑制”J.Biol.Chem.269。

Taro Tachibana: "Loss of RCC1 leads to suppression of nuclear protein import in living cells." J.Biol.Chem.Vol.269. 24542-24545 (1994)

Taro Tachibana：“RCC1 的缺失会导致活细胞中核蛋白输入的抑制。”

Yumiko Okuno: "70-KDa heat-shock cognate protein colocalizes with karyophilic proteins into the nucleus during their transport in vitro." Experimental Cell Research. 206. 134-142 (1993)

Yumiko Okuno：“70-KDa 热休克同源蛋白在体外运输过程中与亲核蛋白共定位到细胞核中。”