在SNX-BAR对应物Vps5和Vin1中的N端信号指导内体外复合体形成
Shawn P Shortill1,2, Mia S Frier1,2, Michael Davey2
1Department of Medical Genetics, University of British Columbia, Vancouver, BC VH6 3N1, Canada.
Molecular biology of the cell
|April 10, 2024
概括
排序nexin (SNX) 蛋白,Vin1和Vps5,使用独特的N-终端信号来组装不同的内体层. 这扩大了对酵母中VINE和逆转激素复合体形成的理解.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白相互作用 蛋白相互作用
背景情况:
- 内体外套对于细胞内贩运至关重要,利用膜结合子单元,如排序nexin (SNX) 蛋白.
- 像Saccharomyces cerevisiae Vin1和Vps5这样的SNX-BAR蛋白质,聚集成不同的内体外层复合体 (VINE和逆转蛋白).
- SNX-BAR 蛋白质的 BAR 域对于复杂的组装和膜结合至关重要,但非结构化的 N 终端域也在外层形成中发挥作用.
研究的目的:
- 在SNX-BAR对应物Vin1和Vps5中映射N终端信号,这些对应物在体内调节内体外层的组装和功能.
- 研究由Vin1和Vps5的N端介导的特定相互作用,分别形成VINE和逆转激素复合体.
- 探索使用乳酵母乳酸菌 (Kluyveromyces lactis) 在SNX-BAR外套组合中N端信号的进化含义.
主要方法:
- 在Saccharomyces cerevisiae SNX-BAR类似物Vin1和Vps5.5中的N端序列特征的体内分析.
- 绘制SNX-BAR N-终端和其他外层复杂子单元 (Vrl1,Vps29) 之间的蛋白质-蛋白质相互作用的映射.
- 从Kluyveromyces lactis中对Vps5进行比较分析,以推断祖先的N-终端信号机制.
主要成果:
- Vin1利用其N端的多基区域和相邻的疏水动机来结合Vrl1并组装VINE外层.
- Vps5的N端与复原体子单元Vps29在两个位置相互作用,包括一个保存的疏水口袋.
- 对Kluyveromyces lactis Vps5的分析表明,祖先酵母可能在VINE和逆转激素组合中使用了嵌套的N端信号.
结论:
- 除了BAR域合之外,特定的N端序列特征决定了Vps5家族SNX-BAR内体层的组装.
- 在Vin1和Vps5中,不同的N终端信号介导它们的招募到特定的外层复合体 (VINE和逆转子).
- 这些发现扩大了对内体外组装机制及其进化多样化的理解.
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