ROS-induced cytosolic release of PGAM5 accelerates cancer progression via MST3-YAP axis

Aberrant mtROS release in response to mitochondrial stress are considered to be a major novel feature of neoplastic transformation. However, the molecular mechanisms by which mtROS contribute to CRC development have not been fully elucidated. In this study, we showed that upon sensing the mtROS signal, the mitochondrially localized phosphatase PGAM5 undergoes cleavage in the mitochondrial transmembrane domain, and then the Cleaved PGAM5 is released into the cytoplasm. Subsequently, Cleaved PGAM5 binds to the kinase MST3 in the cytoplasm to promote MST3 dephosphorylation, resulting in a decrease in MST3 activity. Importantly, MST3 inactivation failed to regulate YAP phosphorylation, leading to YAP translocation into the nucleus, consequently promoting CRC proliferation and metastasis. Collectively, our findings identified the PGAM5-MST3-YAP axis as an important molecular mechanism through which mtROS promotes CRC development. To investigate the function of MST3 in CRC regulation, we generated MST3 intestinal epithelial knockout mice and treated them with AOM&DSS.We then performed gene expression profiling using mRNA-seq data from the intestinal epithelium of littermate mice.