一个BBS蛋白质的核心复合体与GTPase Rab8合作,促进纤毛膜生物发生
Maxence V Nachury1, Alexander V Loktev, Qihong Zhang
1Genentech, Inc., South San Francisco, CA 94080, USA. nachury@gene.com
Cell
|June 19, 2007
概括
巴德特-比德尔综合征 (BBS) 综合体,称为BBSome,对于初级毛形成至关重要. 这个复合体中的缺陷会破坏囊泡运输,导致BBS症状.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 初级膜功能障碍是巴德特-比德尔综合征 (BBS) 发病的核心原因.
- BBS的症状包括肥胖,视网膜退化和病.
- 尽管已经确定了12个BBS基因,但BBS的分子基础仍然不清楚.
研究的目的:
- 为了阐明巴德特-比德尔综合征的分子基础.
- 为了确定BBS蛋白在纤维细胞生成中的功能.
主要方法:
- 一个由七个保存的BBS蛋白质 (BBSome) 组成的复合体的识别和表征.
- 在细胞质结构和初级眼中对BBSome的定位研究.
- 研究了 Rab8 GDP/GTP 交换因子在 BBSome 功能和纤维细胞生成中的作用.
- 利用斑马鱼模型来评估被破坏的纤毛生成的体内影响.
主要成果:
- 一个由七个蛋白质组成的复合体,BBSome,被确定并定位在中心卫星和膜上.
- BBSome对于纤维形成是必不可少的,但对于中心卫星功能不是.
- Rab8 GTPase与基底体的BBSome相互作用,对初级膜扩展至关重要.
- 抑制Rab8 (GTP) 生产阻断了纤毛发育,并在斑马鱼中诱导了BBS表型.
结论:
- 通过调解囊泡运输,BBSome在初级乳毛形成中发挥着关键作用.
- 由于BBS某些缺陷,功能障碍的囊泡运输到主,可能导致巴德特-比德尔综合征.
- 针对BBSome-Rab8通道为BBS提供了潜在的治疗途径.
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