title: AMP-Activated Protein Kinase Regulates the Cell Surface Proteome and Integrin Membrane Traffic.
abstract: The cell surface proteome controls numerous cellular functions including cell migration and adhesion, intercellular communication and nutrient uptake. Cell surface proteins are controlled by acute changes in protein abundance at the plasma membrane through regulation of endocytosis and recycling (endomembrane traffic). Many cellular signals regulate endomembrane traffic, including metabolic signaling; however, the extent to which the cell surface proteome is controlled by acute regulation of endomembrane traffic under various conditions remains incompletely understood. AMP-activated protein kinase (AMPK) is a key metabolic sensor that is activated upon reduced cellular energy availability. AMPK activation alters the endomembrane traffic of a few specific proteins, as part of an adaptive response to increase energy intake and reduce energy expenditure. How increased AMPK activity during energy stress may globally regulate the cell surface proteome is not well understood. To study how AMPK may regulate the cell surface proteome, we used cell-impermeable biotinylation to selectively purify cell surface proteins under various conditions. Using ESI-MS/MS, we found that acute (90 min) treatment with the AMPK activator A-769662 elicits broad control of the cell surface abundance of diverse proteins. In particular, A-769662 treatment depleted from the cell surface proteins with functions in cell migration and adhesion. To complement our mass spectrometry results, we used other methods to show that A-769662 treatment results in impaired cell migration. Further, A-769662 treatment reduced the cell surface abundance of β1-integrin, a key cell migration protein, and AMPK gene silencing prevented this effect. While the control of the cell surface abundance of various proteins by A-769662 treatment was broad, it was also selective, as this treatment did not change the cell surface abundance of the transferrin receptor. Hence, the cell surface proteome is subject to acute regulation by treatment with A-769662, at least some of which is mediated by the metabolic sensor AMPK.
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Eden
authors.initials: E
authors.lastname: Ross
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Rehman
authors.initials: R
authors.lastname: Ata
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Thanusi
authors.initials: T
authors.lastname: Thavarajah
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Sergei
authors.initials: S
authors.lastname: Medvedev
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Peter
authors.initials: P
authors.lastname: Bowden
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: John G
authors.initials: JG
authors.lastname: Marshall
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
authors.forename: Costin N
authors.initials: CN
authors.lastname: Antonescu
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D019921:Biotinylation; D001713:Biphenyl Compounds; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D002465:Cell Movement / Q000187:drug effects; D005786:Gene Expression Regulation; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D013058:Mass Spectrometry; D021381:Protein Transport / Q000187:drug effects; D020543:Proteome / Q000187:drug effects / Q000378:metabolism*; D011753:Pyrones / Q000494:pharmacology*; D013876:Thiophenes / Q000494:pharmacology*
chemical_list: D001713:Biphenyl Compounds; D016023:Integrins; D020543:Proteome; D011753:Pyrones; D013876:Thiophenes; D055372:AMP-Activated Protein Kinases; C512408:4-hydroxy-3-(4-(2-hydroxyphenyl)phenyl)-6-oxo-7H-thieno(2,3-b)pyridine-5-carbonitrile