Protein kinase a-dependent phosphorylation of Rap1 regulates its membrane localization and cell migration

Abstract

Background: The small G protein Rap1 is phosphorylated within its carboxyl terminus by the cAMP-dependent protein kinase PKA. Results: This phosphorylation removes Rap1 from the plasma membrane to limit Rap1 signaling. Conclusion: Rap1 phosphorylation switches Rap1 off the membrane and terminates its activation. Significance: Carboxyl-terminal phosphorylation may be common among small G proteins to regulate GTP/GDP cycling and downstream signaling. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.