Effect of PIP2 binding on the membrane docking geometry of PKC alpha C2 domain: an EPR site-directed spin-labeling and relaxation study.

ABSTRACT: Protein kinase C isoform alpha (PKCalpha) is a ubiquitous, conventional PKC enzyme that possesses a conserved C2 domain. Upon activation by cytoplasmic Ca (2+) ions, the C2 domain specifically binds to the plasma membrane inner leaflet where it recognizes the target lipids phosphatidylserine (PS) and phosphatidylinositol-4,5-bisphosphate (PIP 2). The membrane penetration depth and docking angle of the membrane-associated C2 domain is not well understood. The present study employs EPR site-directed spin labeling and relaxation methods to generate a medium-resolution model of the PKCalpha C2 domain docked to a membrane of lipid composition similar to the plasma membrane inner leaflet. The approach measures EPR depth parameters for 10 function-retaining spin labels coupled to the C2 domain, a

SUBMITTER: Landgraf KE 

PROVIDER: S-EPMC3633444 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature