结构功能分析显示,Arabidopsis thaliana HDA7 是一个不活跃的基因素脱乙酶
Ketul Saharan1,2, Somanath Baral1, Nausad Hossain Shaikh1
1Structural Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, 751023, India.
Current research in structural biology
|March 11, 2024
概括
阿拉比多普西斯HDA7,一种组分素脱乙酶,在结构上具有特征,并且由于其活性部位的突变,被发现具有催化不活性. 它的同类仅限于Brassicaceae家族.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 植物科学 植物科学
背景情况:
- 基因脱乙酶 (HDACs) 调节基因表达,对植物发育至关重要.
- 在植物中,Rpd3/Hda1家族的HDACs影响应激反应,种子,胚胎和花发育.
研究的目的:
- 为了描述Arabidopsis thaliana HDA7,一个I类Rpd3/Hda1家族的HDAC.
- 研究AtHDA7.7的结构和催化性能.
主要方法:
- 复合表达和净化AtHDA7基因素脱乙酶域.
- 微角X射线散射 (SAXS) 和分析超离心 (AUC) 用于溶液研究.
- 用于结构确定的X射线晶体学.
- 序列分析和体外活性测定.
主要成果:
- AtHDA7存在于溶液中的单体,并采用典型的α/β氨酶折叠.
- "XDXH"基因中的关键催化残留物 (Asp和His) 发生突变,防止Zn2+结合.
- 在实验室中,AtHDA7作为HDAC具有催化不活性.
- AtHDA7的同类只在布拉西卡家族中发现.
结论:
- AtHDA7是一种催化不活的HDAC,可能是由于进化突变.
- 由于AtHDA7同类的分布有限,这表明AtHDA7在Brassicaceae中扮演着特殊的角色.
- HDA7可能是通过基因组重复事件从HDA6进化而来的.
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