在细胞周期晚期所需的新酵母活性蛋白样基因
1Laboratoire de Biochimie, Centre National de la Recherche Scientifique, Strasbourg, France.
Nature
|January 9, 1992
概括
研究人员发现了ACT2,这是一种新型酵母基因,它编码了一种类似actin的蛋白质,对细胞生长至关重要. 这种蛋白质与47%的actin相同,在细胞骨重组中发挥作用,突出了真核生物中actin类蛋白质的保存功能.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 动氨酸是一种高度保守的细胞骨蛋白质,对真核细胞的功能如运动和分裂至关重要.
- 酵母菌Saccharomyces cerevisiae有一个必不可少的活性蛋白基因 (ACT1),对细胞组织和极化生长至关重要.
- 之前的研究集中在高度保守的actin蛋白,对不同的actin样分子的知识有限.
研究的目的:
- 为了描述新发现的酵母基因ACT2及其编码的蛋白质.
- 研究Act2蛋白的功能和结构特性.
- 探索真核生物中不同类型的行为蛋白的进化意义.
主要方法:
- 在Saccharomyces cerevisiae中鉴定和描述ACT2的基因.
- 蛋白质序列分析和与已知actin结构进行比较.
- 在已知的3D结构上,Act2的结构叠加.
- 对酵母菌植物生长的ACT2基因要求的评估.
主要成果:
- 发现ACT2,一种酵母分裂基因,编码391氨基酸蛋白 (Act2),与酵母actin相同47%.
- Act2蛋白在聚合和结合关键的循环中表现出显著的分歧,而核心域仍然保留.
- ACT2对于酵母细胞的植物生长至关重要.
- 其他真核生物中也存在类似actin类蛋白质的相关基因,这表明它们的功能保留了下来.
结论:
- 该Act2蛋白代表了第一个描述的高度分离的actin分子.
- 结构和生理学数据表明,Act2在细胞循环期间的细胞骨重组中起作用.
- 发现ACT2及其保存的同类突显了除了规范性actin之外的actin类蛋白质的重要性.
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