Faculty Collaboration Database

The DPY-30 domain and its flanking sequence mediate the assembly and modulation of flagellar radial spoke complexes. Mol Cell Biol 2012 Oct;32(19):4012-24

Date

08/02/2012

Pubmed ID

22851692

Pubmed Central ID

PMC3457544

DOI

10.1128/MCB.06602-11

Scopus ID

2-s2.0-84868709371 (requires institutional sign-in at Scopus site)   15 Citations

Abstract

RIIa is known as the dimerization and docking (D/D) domain of the cyclic AMP (cAMP)-dependent protein kinase. However, numerous molecules, including radial spoke protein 2 (RSP2) in Chlamydomonas flagella, also contain an RIIa or a similar DPY-30 domain. To elucidate new roles of D/D domain-containing proteins, we investigated a panel of RSP2 mutants. An RSP2 mutant had paralyzed flagella defective in RSP2 and multiple subunits near the spokehead. New transgenic strains lacking only the DPY-30 domain in RSP2 were also paralyzed. In contrast, motility was restored in strains that lacked only RSP2's calmodulin-binding C-terminal region. These cells swam normally in dim light but could not maintain typical swimming trajectories under bright illumination. In both deletion transgenic strains, the subunits near the spokehead were restored, but their firm attachment to the spokestalk required the DPY-30 domain. We postulate that the DPY-30-helix dimer is a conserved two-prong linker, required for normal motility, organizing duplicated subunits in the radial spoke stalk and formation of a symmetrical spokehead. Further, the dispensable calmodulin-binding region appears to fine-tune the spokehead for regulation of "steering" motility in the green algae. Thus, in general, D/D domains may function to localize molecular modules for both the assembly and modulation of macromolecular complexes.

Author List

Gopal R, Foster KW, Yang P

Author

Pinfen Yang PhD Associate professor in the Biological Sciences department at Marquette University

MESH terms used to index this publication - Major topics in bold

Amino Acid Sequence
Animals
Cell Movement
Chlamydomonas
Cyclic AMP-Dependent Protein Kinases
Flagella
Humans
Models, Molecular
Molecular Sequence Data
Plant Proteins
Protein Structure, Secondary
Protein Structure, Tertiary
Sequence Alignment