基,活性PKM2抑制IP3受体,可能需要GRP75作为额外的相互作用伙伴
Fernanda O Lemos1, Ian de Ridder1, Larry Wagner2
1Laboratory of Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, KU Leuven, Herestraat 49, Campus Gasthuisberg O&N1 - B802, 3000 Leuven, Belgium.
Biochimica et biophysica acta. Molecular cell research
|July 22, 2024
概括
酸激酶M2 (PKM2) 四聚体形成通过与伊诺西1,4,5-三酸盐受体 (IP3R) 相互作用来抑制信号. 这种相互作用是由GRP75调节的,形成了一个调节细胞水平的复合体.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 酸盐激酶M2 (PKM2) 是一个关键的糖解酶.
- PKM2与内醇1,4,5-三酸盐受体 (IP3R) 相互作用,抑制细胞质升高.
- PKM2存在于多种寡合体形式 (单体,二聚体,四聚体),具有不同的催化活性.
研究的目的:
- 研究PKM2与IP3Rs相互作用的基础分子机制.
- 确定PKM2的寡合状态和催化活性在IP3R调节中的作用.
- 确定PKM2-IP3R信号通路中的潜在中间因素.
主要方法:
- 用TEPP-46进行细胞治疗以稳定PKM2四度体.
- PKM2淘汰和突变细胞系分析.
- 在体外结合测试用纯化的蛋白质和.
- 在核上的补丁电生理学.
- 免疫沉试验. 免疫沉试验.
主要成果:
- TEPP-46治疗增强了PKM2活性,并抑制了IP3R介导的信号.
- 活跃的四重基PKM2突变体抑制了IP3R介导的释放,与不活跃的突变体不同.
- 实验室和电生理学测试显示没有直接的PKM2-IP3R相互作用.
- 免疫沉显示GRP75是与PKM2和IP3Rs复合的一部分.
- 一个特定的干扰了PKM2:IP3R,PKM2:GRP75和GRP75:IP3R的相互作用.
结论:
- 具有催化活性,四度基PKM2抑制IP3R介导的信号传递.
- 相互作用不是直接的,而是通过涉及GRP75.5的多蛋白质复合体进行介导.
- 这种含有GRP75的复合物对PKM2细胞的调节至关重要.
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