通过p110γ螺旋域的构造变化介导的PI3Kγ的Allosteric激活或抑制
Noah J Harris1, Meredith L Jenkins1, Sung-Eun Nam2
1Department of Biochemistry and Microbiology, University of Victoria, Victoria, Canada.
eLife
|July 7, 2023
概括
新的研究揭示了氏酸3-激酶 (PI3Kγ) 的螺旋域在免疫信号传递中起着关键的调节作用. 这一发现为开发用于治疗干预的全抑制剂开辟了新的途径.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
背景情况:
- 酸3-激酶 (PI3Kγ) 是免疫细胞信号传递中的关键酶,在各种细胞表面受体的下游.
- PI3Kγ存在于两个不同的复合体 (p110γ-p101和p110γ-p84) 中,具有不同的激活机制.
研究的目的:
- 阐明p110γ螺旋域在PI3Kγ脂类激酶活性中的新型调节作用.
- 定义纳米体对全抑制的分子基础.
- 研究PKCβ酸化对PI3Kγ复合体活性的影响.
主要方法:
- 低温电子显微镜的使用方法
- -交换质谱法 (HDX-MS) 是一种质谱法.
- 生物化学测定 生物化学测定
主要成果:
- 在不同的PI3Kγ复合体中,确定了p110γ螺旋域的新型全osteric调节功能.
- 确定一种抑制性纳米体使螺旋域刚性化,降低ATP周转率,而不会影响膜招募或联合因子结合.
- 发现的PKCβ酸化通过诱导螺旋域的部分展开来选择性地激活p110γ-p84复合体,这是一个被纳米体抑制的过程.
结论:
- 在p110γ-p84和p110γ-p101复合体中,p110γ螺旋域表现出明显的全调节.
- 调节PI3Kγ活动可以通过酸化或全抑制来实现.
- 这些发现为开发用于治疗应用的新型PI3Kγ全抑制剂提供了基础.
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