Zyxin directly binds to chromosomal DNA and is linked with mitochondrial integrity and apoptosis.

Abstract

Human zyxin is a key component of the focal adhesion complex, playing a role in mediating cell-cell adhesion and cytoskeletal dynamics. Moreover, zyxin shuttles between the cytoplasm and the nucleus, where it contributes to regulating gene expression. Although identified over 30 years ago, zyxin's nuclear functions, particularly in relation to cancer, remain largely unexplored. In this study, we profiled zyxin binding to chromosomal DNA using metastatic prostate carcinoma PC3M cells as a model. Our ChIP-Seq results revealed that zyxin binds to chromosomal DNA, with mitochondrial pseudogenes as the primary targets. Furthermore, we demonstrated that the LIM domains of zyxin are sufficient for DNA binding and that zyxin knockdown leads to transcriptional changes in mitochondrial pseudogenes. Additionally, zyxin knockdown impacted several other genes associated with mitochondrial integrity and apoptosis, resulting in disturbances in MTCO2P2 RNA localization, mitochondrial membrane potential, increased reactive oxygen species, alterations in the cell cycle, and progression towards apoptosis. Overall, our work shows that zyxin directly interacts with nuclear DNA and regulates the transcription of mitochondrial pseudogenes, emphasizing its role in modulating mitochondrial function.