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Updated: Jun 4, 2025

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A Fluorescence-based Assay of Phospholipid Scramblase Activity
Published on: September 20, 2016
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TMEM63/OSCA家族的膜结构响应性脂质杂乱酶活性
Yugo Miyata1, Megumi Nishimura1, Aya Nagata1
1Department of Medical Chemistry, Medical Research Laboratory, Institute of Integrated Research, Institute of Science Tokyo, Japan.
FEBS letters
|December 23, 2024
概括
脊椎动物TMEM63B的ortologs作为膜结构响应的scramblases,破坏了等离子膜的脂不对称性. 这种scramblase活性在物种之间保持,并与致病变异相关.
科学领域:
- 细胞生物学 细胞生物学
- 膜生物学 膜生物学
- 生物化学 生物化学
背景情况:
- 脂在等离子膜 (PM) 中分布不对称.
- 斯克兰布莱斯是破坏这种不对称性的蛋白质,通过混合脂.
- 鼠标Tmem63b最近被确定为一种膜结构响应的scramblase,属于TMEM63/OSCA离子通道家族.
研究的目的:
- 为了研究TMEM63/OSCA家族内斯克兰布拉斯活性的保存.
- 为了确定从脊椎动物中获得的TMEM63B Orthologs是否表现出scramblase活性.
- 分析人类TMEM63B变异对杂酶活性的功能影响.
主要方法:
- 在缺少Tmem63b的小鼠亲B细胞中表达人类TMEM63对应物,TMEM63B正义物和植物OSCA1.1.
- 在等离子体膜上的scramblase活性的功能性评估.
- 对十种先前确定的致病性人类TMEM63B变种的分析.
主要成果:
- 脊椎动物TMEM63B的 ортолог证明了在血膜上的杂酶活性.
- 在十种致病性人类TMEM63B变体中,有九种表现出构成性杂乱酶活性.
- 在脊椎动物TMEM63B的ortologs中,PM的scramblase活性是保留的.
结论:
- TMEM63b的膜结构响应性杂酶活性在脊椎动物的TMEM63B正位体中得到保留.
- 致病性TMEM63B变体经常表现出构成性混杂酶活性,突出了受调节的脂不对称的重要性.
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