Department of Microbiology, School of Medical Laboratory, Tianjin Medical University, Tianjin 300203, China.
Department of Clinical Laboratory, Tianjin Children's Hospital/Tianjin University Children's Hospital, Tianjin 300134, China.
Int J Biol Sci. 2024 Jan 1;20(2):516-536. doi: 10.7150/ijbs.84399. eCollection 2024.
A key player in mitochondrial respiration, p32, often referred to as C1QBP, is mostly found in the mitochondrial matrix. Previously, we showed that p32 interacts with DLAT in the mitochondria. Here, we found that p32 expression was reduced in ccRCC and suppressed progression and metastasis in ccRCC animal models. We observed that increasing p32 expression led to an increase in oxidative phosphorylation by interacting with DLAT, thus, regulating the activation of the pyruvate dehydrogenase complex (PDHc). Mechanistically, reduced p32 expression, in concert with DLAT, suppresses PDHc activity and the TCA cycle. Furthermore, our research discovered that p32 has a direct binding affinity for copper, facilitating the copper-induced oligomerization of lipo-DLAT specifically in ccRCC cells. This finding reveals an innovative function of the p32/DLAT/copper complex in regulating glycometabolism and the TCA cycle in ccRCC. Importantly, our research provides important new understandings of the underlying molecular processes causing the abnormal mitochondrial metabolism linked to this cancer.
p32 是线粒体呼吸的关键因子,也被称为 C1QBP,主要存在于线粒体基质中。此前,我们发现 p32 与线粒体中的 DLAT 相互作用。在这里,我们发现 p32 在 ccRCC 中表达降低,并在 ccRCC 动物模型中抑制进展和转移。我们观察到增加 p32 表达与 DLAT 相互作用会增加氧化磷酸化,从而调节丙酮酸脱氢酶复合物(PDHc)的激活。从机制上讲,p32 表达降低与 DLAT 一起抑制 PDHc 活性和 TCA 循环。此外,我们的研究发现 p32 与铜具有直接的结合亲和力,促进铜诱导的 lipo-DLAT 寡聚化,特别是在 ccRCC 细胞中。这一发现揭示了 p32/DLAT/铜复合物在调节 ccRCC 中的糖代谢和 TCA 循环中的创新功能。重要的是,我们的研究提供了对导致这种癌症相关异常线粒体代谢的潜在分子过程的重要新认识。