核蛋白RanBP2具有SUMO1 E3结合酶活性
Andrea Pichler1, Andreas Gast, Jacob S Seeler
1Max-Planck Institute for Biochemistry, Am Klopferspitz 18a, 82152 Martinsried, Germany.
Cell
|January 17, 2002
概括
核蛋白RanBP2/Nup358表现出类似SUMO1 E3的活性,通过与Ubc9酶相互作用来增强SUMOylation. 这一发现将蛋白质修饰与NPC的核进口联系起来.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 通过SUMOylation的翻译后修饰调节关键蛋白质功能,包括相互作用,局部化和稳定性.
- SUMOylation途径涉及E1酶 (Aos1/Uba2) 和E2酶 (Ubc9),PIAS蛋白被确定为E3类因子.
- 核孔综合体 (NPC) 对于调节核与细胞质之间的运输至关重要.
研究的目的:
- 为了研究核蛋白RanBP2/Nup358.8.的潜在的SUMO E3类活性.
- 描述负责RanBP2/Nup358的SUMO E3类活动的机制和特定域.
- 确定RanBP2/Nup358介导的SUMOylation与核进口有关的功能影响.
主要方法:
- 生物化学测试以评估SUMO1转移增强.
- 蛋白相互作用研究以确定RanBP2/Nup358和Ubc9.9之间的相互作用.
- 在RanBP2/Nup358.8内绘制SUMO E3类活动域的映射.
- 在NPC进行SUMOylation活动的局部化研究.
主要成果:
- RanBP2/Nup358显示出SUMO1 E3类活性,独立于PIAS蛋白和RING指纹图案.
- 兰BP2/Nup358直接与E2酶Ubc9.9相互作用
- 这种类似E3的活性位于RanBP2/Nup358.8的特定33kDa域内.
- 由RanBP2/Nup358介导的SUMOylation活性局部化到NPC的细胞质纤维.
结论:
- 兰BP2/Nup358作为一种新的SUMO1 E3样联酶.
- 这项研究确定了由核介导的SUMOylation与核进口过程之间的直接联系.
- 这些发现表明,蛋白质的修饰和运输是NPC的协调活动.
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