A flagellar A-kinase anchoring protein with two amphipathic helices forms a structural scaffold in the radial spoke complex. J Cell Biol 2012 Nov 12;199(4):639-51
Date
11/14/2012Pubmed ID
23148234Pubmed Central ID
PMC3494852DOI
10.1083/jcb.201111042Scopus ID
2-s2.0-84871946433 (requires institutional sign-in at Scopus site) 28 CitationsAbstract
A-kinase anchoring proteins (AKAPs) contain an amphipathic helix (AH) that binds the dimerization and docking (D/D) domain, RIIa, in cAMP-dependent protein kinase A (PKA). Many AKAPs were discovered solely based on the AH-RIIa interaction in vitro. An RIIa or a similar Dpy-30 domain is also present in numerous diverged molecules that are implicated in critical processes as diverse as flagellar beating, membrane trafficking, histone methylation, and stem cell differentiation, yet these molecules remain poorly characterized. Here we demonstrate that an AKAP, RSP3, forms a dimeric structural scaffold in the flagellar radial spoke complex, anchoring through two distinct AHs, the RIIa and Dpy-30 domains, in four non-PKA spoke proteins involved in the assembly and modulation of the complex. Interestingly, one AH can bind both RIIa and Dpy-30 domains in vitro. Thus, AHs and D/D domains constitute a versatile yet potentially promiscuous system for localizing various effector mechanisms. These results greatly expand the current concept about anchoring mechanisms and AKAPs.
Author List
Sivadas P, Dienes JM, St Maurice M, Meek WD, Yang PAuthors
Martin St. Maurice PhD Associate Professor in the Biology department at Marquette UniversityPinfen Yang PhD Associate professor in the Biological Sciences department at Marquette University
MESH terms used to index this publication - Major topics in bold
A Kinase Anchor ProteinsCells, Cultured
Chlamydomonas reinhardtii
Flagella
Hydrophobic and Hydrophilic Interactions
Models, Molecular
Mutagenesis
Plant Proteins
Protein Structure, Secondary
Protozoan Proteins
