对PKA-Cα的氧化修正不同地影响其基质选择
Jeannette Delva-Wiley1, Ese S Ekhator1, Laquaundra L Adams1
1Department of Biology, North Carolina A&T State University, Greensboro, NC 27411, USA.
Life (Basel, Switzerland)
|September 28, 2023
概括
循环AMP依赖蛋白激酶α (PKA-Cα) 的氧还原修饰改变了其基质特异性. 氧化对各种基质的PKA-Cα活性产生不同的影响,揭示了氧化还原和酸化信号之间的交叉声.
科学领域:
- 生物化学 生物化学
- 细胞信号传输 细胞信号传输
- 酶学 是一种酶学.
背景情况:
- 循环AMP依赖蛋白激酶 (PKA) 调节关键的细胞过程,并与糖尿病和神经退行等疾病有关.
- PKA (PKA-Cα) 催化子单元的α异型在位于活性部位的C199处经历氧化.
- PKA-Cα C199氧化对基质选择的功能影响在很大程度上是未知的.
研究的目的:
- 调查C199处PKA-Cα的氧化还原修饰如何影响其基质特异性.
- 探索氧化对PKA-Cα对各种基质的激酶活性的影响.
- 了解由PKA介导的氧化还原和酸化信号通路之间的相互作用.
主要方法:
- 生物化学测定包括转酸化和稳定状态动力学.
- 生物物理技术,如表面等离子体共振和光极化.
- 研究了二氧化物和H2O2诱导的氧化对PKA-Cα活性的影响.
主要成果:
- 对PKA-Cα的氧还原修饰会对其对不同基质的活性产生不同的影响.
- 通过二胺介导的氧化减少了PKA-Cα在Kemptide和CREBtide上的活性,但没有Crosstide.
- 依赖H2O2的氧化最初增加了基板上的PKA-Cα活性,其度取决于度的变化.
结论:
- 在C199处PKA-Cα的氧化改变了基质选择,突出了氧化还原和酸化信号之间的交叉声.
- 研究结果提供了关于PKA在整合氧化还原和酸化信号中的作用的见解.
- C199的保守性质表明,对AGC激酶家族成员在氧化还原依赖信号传递中具有更广泛的影响.
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