Arg kinase-binding protein 2 (ArgBP2) interaction with ?-actinin and actin stress fibers inhibits cell migration.

ABSTRACT: Cell migration requires dynamic remodeling of the actomyosin network. We report here that an adapter protein, ArgBP2, is a component of ?-actinin containing stress fibers and inhibits migration. ArgBP2 is undetectable in many commonly studied cancer-derived cell lines. COS-7 and HeLa cells express ArgBP2 (by Western analysis), but expression was detectable only in approximately half the cells by immunofluorescence. Short term clonal analysis demonstrated 0.2-0.3% of cells switch ArgBP2 expression (on or off) per cell division. ArgBP2 can have a fundamental impact on the actomyosin network: ArgBP2 positive COS-7 cells, for example, are clearly distinguishable by their denser actomyosin (stress fiber) network. ArgBP2? binding to ?-actinin appears to underlie its ability to localize to stress fibers and decrease cell migration. We map a small ?-actinin binding region in ArgBP2 (residues 192-228) that is essential for these effects. Protein kinase A phosphorylation of ArgBP2? at neighboring Ser-259 and consequent 14-3-3 binding blocks its interaction with ?-actinin. ArgBP2 is known to be down-regulated in some aggressively metastatic cancers. Our work provides a biochemical explanation for the anti-migratory effect of ArgBP2.

SUBMITTER: Anekal PV 

PROVIDER: S-EPMC4303664 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature