The flagellar motility of Chlamydomonas pf25 mutant lacking an AKAP-binding protein is overtly sensitive to medium conditions. Mol Biol Cell 2006 Jan;17(1):227-38
Date
11/04/2005Pubmed ID
16267272Pubmed Central ID
PMC1345661DOI
10.1091/mbc.e05-07-0630Scopus ID
2-s2.0-30044437241 (requires institutional sign-in at Scopus site) 26 CitationsAbstract
Radial spokes are a conserved axonemal structural complex postulated to regulate the motility of 9 + 2 cilia and flagella via a network of phosphoenzymes and regulatory proteins. Consistently, a Chlamydomonas radial spoke protein, RSP3, has been identified by RII overlays as an A-kinase anchoring protein (AKAP) that localizes the cAMP-dependent protein kinase (PKA) holoenzyme by binding to the RIIa domain of PKA RII subunit. However, the highly conserved docking domain of PKA is also found in the N termini of several AKAP-binding proteins unrelated to PKA as well as a 24-kDa novel spoke protein, RSP11. Here, we report that RSP11 binds to RSP3 directly in vitro and colocalizes with RSP3 toward the spoke base near outer doublets and dynein motors in axonemes. Importantly, RSP11 mutant pf25 displays a spectrum of motility, from paralysis with flaccid or twitching flagella as other spoke mutants to wildtype-like swimming. The wide range of motility changes reversibly depending on the condition of liquid media without replacing defective proteins. We postulate that radial spokes use the RIIa/AKAP module to regulate ciliary and flagellar beating; absence of the spoke RIIa protein exposes a medium-sensitive regulatory mechanism that is not obvious in wild-type Chlamydomonas.
Author List
Yang C, Yang PAuthor
Pinfen Yang PhD Associate professor in the Biological Sciences department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
Adaptor Proteins, Signal TransducingAmino Acid Sequence
Animal Migration
Animals
Base Sequence
Chlamydomonas reinhardtii
Conserved Sequence
Culture Media
Cyclic AMP-Dependent Protein Kinases
Electrophoresis, Gel, Two-Dimensional
Flagella
Molecular Sequence Data
Mutation
Plant Proteins
Protein Binding
Protozoan Proteins
Sequence Alignment
Sequence Homology, Amino Acid
