利用人類蛋白質體晶片探討ATP合成酶之交互作用蛋白

Abstract

ATP synthase is essential for almost all organisms because ATP is the common “energy currency” of cells. It is a multimeric protein complex including beta subunit (ATP5B) that catalyzes the synthesis of ATP from ADP and phosphate. Although ATP synthase was initially thought to be located exclusively in the mitochondrial inner membrane, its presence has now been described on the outside of the plasma membrane of both normal cells (e.g. endothelial cells, hepatocytes and adipocytes) and tumor cells. We are interested to understand whether ATP5B interacts with different proteins and performs different functions. Here, we perform a human proteome microarray to reveal the novel interacting proteins with ATP5B and identified 16 proteins which interact strongly with ATP5B. The identified ATP5B interacting proteins are functionally enriched in mitogen activated protein kinase 12 (MAPK12) dependent pathways. Our previous results showed that ATP5B was overexpressed on the plasma membrane with the potential as a cell proliferation regulator in both breast and lung cancers. Hence we further combined ATP synthase inhibitor, citrovirodin, and MAPK12 inhibitor, and found this combination leads to addictive inhibition on lung cancer cell proliferation. Taken together, these findings suggest that these interacting proteins of ATP5B as a cell proliferation signal linking to MAPK12 in response to a variety of extracellular stimuli.