The regulation of the cell surface proteome by amp-activated protein kinase

The cell-surface proteome controls numerous cellular functions and is dynamically controlled by endocytosis and recycling under different cellular conditions. Energy stress is a state in which a cell must engage adaptive responses to ensure survival, including remodelling of the cell-surface proteome. AMP-activated protein kinase (AMPK) is an important metabolic regulator in the cell. Recent studies suggest AMPK activation may alter the endocytosis of a few specific proteins. How increased AMPK activity globally regulates the cell surface proteome is not known. I have developed a method to isolate the cell surface proteome from cultured cells. Coupling this method to quantitative mass spectrometry has allowed systematic identification of changes in the cell-surface proteome upon metabolic regulation. I found that activation of AMPK results in robust changes in the cell surface proteome, including cell adhesion and migration proteins. I confirmed that AMPK activation elicits a decrease in the cell surface abundance of the adhesion and migration protein β1-integrin, and that this is correlated with altered function of the endocytosis protein Dab2. Thus, my research furthers our understanding of how AMPK regulates the cell surface proteome and the specific mechanism by which AMPK regulates cellular adhesion and migration.