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在ERK2的D-招募部位内,依赖过氧化的氧化会改变其基质选择
Anthony E Postiglione1,2, Laquaundra L Adams1, Ese S Ekhator1
1Department of Biology, North Carolina A&T State University, Greensboro, NC 27411, USA.
iScience
|September 25, 2023
概括
通过过氧化氧化细胞外信号调节激酶1和2 (ERK1/2) 的氧化改变了基质相互作用. 这种氧化还原修饰影响ERK1/2
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 转毒生物学 转毒生物学
背景情况:
- 细胞外信号调节激酶1和2 (ERK1/2) 是关键的信号蛋白,与许多疾病有关.
- ERK1/2活性是通过酸化调节的,但最近的发现表明氧化还原变化也起作用.
- 信号生成的过氧化已被确定为一种可以改变ERK1/2.2的氧化剂.
研究的目的:
- 调查ERK2被过氧化氧化如何影响其与模型基质的相互作用.
- 阐明氧化还原修饰影响ERK2基质选择性的机制.
- 探索ERK1/2氧化对细胞环境中酶活性的功能后果.
主要方法:
- 生物化学测试以评估酶活性和基质结合.
- 计算建模用于预测和理解氧化后的结构变化.
- 位点定向的突变发生,以确定参与氧化和基质相互作用的关键残留物.
- 基于细胞的测试使用HeLa细胞来检查体内ERK1/2活性.
主要成果:
- 在 ERK2 的 D-招募位点上,ERK2 经过在氨酸 159 (C159) 中的硫化.
- 在C159的氧化不同调节ERK2对各种基质的亲和力,在某些基质下降,在其他基质上增加.
- 过氧化物依赖氧化提供了改变ERK2-基质相互作用的机制.
- 氧化ERK1/2在HeLa细胞中表现出对核糖体S6激酶A1 (RSK1) 的增强酸化.
结论:
- ERK1/2的氧化还原修饰,特别是C159的硫化,直接影响其与基质的相互作用.
- 氧化会以基质依赖的方式改变ERK2的基质结合亲和力.
- 这些发现揭示了氧化还原和酸化信号通路之间在酶-基质选择水平上的交叉通道机制.
- 这项研究为了解氧化还原状态如何影响酶信号特异性提供了基础.
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