Hypoxia-induced downregulation of PGK1 crotonylation promotes tumorigenesis by coordinating glycolysis and the TCA cycle
Zihao Guo, Yang Zhang, Haoyue Wang, Liming Liao, Lingdi Ma, Yiliang Zhao, Ronghui Yang, Xuexue Li, Jing Niu, Qiaoyun Chu, Yanxia Fu, Binghui Li, Chuanzhen Yang
Abstract
Protein post-translational modifications (PTMs) are crucial for cancer cells to adapt to hypoxia; however, the functional significance of lysine crotonylation (Kcr) in hypoxia remains unclear. Herein we report a quantitative proteomics analysis of global crotonylome under normoxia and hypoxia, and demonstrate 128 Kcr site alterations across 101 proteins in MDA-MB231 cells. Specifically, we observe a significant decrease in K131cr, K156cr and K220cr of phosphoglycerate kinase 1 (PGK1) upon hypoxia. Enoyl-CoA hydratase 1 (ECHS1) is upregulated and interacts with PGK1, leading to the downregulation of PGK1 Kcr under hypoxia. Abolishment of PGK1 Kcr promotes glycolysis and suppresses mitochondrial pyruvate metabolism by activating pyruvate dehydrogenase kinase 1 (PDHK1). A low PGK1 K131cr level is correlated with malignancy and poor prognosis of breast cancer. Our findings show that PGK1 Kcr is a signal in coordinating glycolysis and the tricarboxylic acid (TCA) cycle and may serve as a diagnostic indicator for breast cancer. The functional relevance of lysine crotonylation in cancer remains to be further explored. Here, the authors show that hypoxia-induced downregulation of PGK1 lysine crotonylation promotes glycolysis and suppresses mitochondrial pyruvate metabolism, contributing to breast cancer progression.