The Journal of Cell Biology
Department of Biological Sciences
For virtually all cilia and eukaryotic flagella, the second messengers calcium and cyclic adenosine monophosphate are implicated in modulating dynein- driven microtubule sliding to regulate beating. Calmodulin (CaM) localizes to the axoneme and is a key calcium sensor involved in regulating motility. Using immunoprecipitation and mass spectrometry, we identify members of a CaM-containing complex that are involved in regulating dynein activity. This complex includes flagellar-associated protein 91 (FAP91), which shares considerable sequence similarity to AAT-1, a protein originally identified in testis as an A-kinase anchor protein (AKAP)- binding protein. FAP91 directly interacts with radial spoke protein 3 (an AKAP), which is located at the base of the spoke. In a microtubule sliding assay, the addition of antibodies generated against FAP91 to mutant axonemes with reduced dynein activity restores dynein activity to wild-type levels. These combined results indicate that the CaM- and spoke-associated complex mediates regulatory signals between the radial spokes and dynein arms.
Dymek EE, Smith EF. A conserved CaM- and radial spoke associated complex mediates regulation of flagellar dynein activity. J Cell Biol. 2007 Nov 5;179(3):515-26. doi: 10.1083/jcb.200703107. Epub 2007 Oct 29. PMID: 17967944; PMCID: PMC2064796.
Dartmouth Digital Commons Citation
Dymek, Erin E. and Smith, Elizabeth F., "A Conserved CaM- and Radial Spoke–Associated Complex Mediates Regulation of Flagellar Dynein Activity" (2007). Dartmouth Scholarship. 1440.