Calmodulin dissociation regulates Myo5 recruitment and function at endocytic sites.

Published

Journal Article

Myosins-I are conserved proteins that bear an N-terminal motor head followed by a Tail Homology 1 (TH1) lipid-binding domain. Some myosins-I have an additional C-terminal extension (C(ext)) that promotes Arp2/3 complex-dependent actin polymerization. The head and the tail are separated by a neck that binds calmodulin or calmodulin-related light chains. Myosins-I are known to participate in actin-dependent membrane remodelling. However, the molecular mechanisms controlling their recruitment and their biochemical activities in vivo are far from being understood. In this study, we provided evidence suggesting the existence of an inhibitory interaction between the TH1 domain of the yeast myosin-I Myo5 and its C(ext). The TH1 domain prevented binding of the Myo5 C(ext) to the yeast WIP homologue Vrp1, Myo5 C(ext)-induced actin polymerization and recruitment of the Myo5 C(ext) to endocytic sites. Our data also indicated that calmodulin dissociation from Myo5 weakened the interaction between the neck and TH1 domains and the C(ext). Concomitantly, calmodulin dissociation triggered Myo5 binding to Vrp1, extended the myosin-I lifespan at endocytic sites and activated Myo5-induced actin polymerization.

Full Text

Duke Authors

Cited Authors

  • Grötsch, H; Giblin, JP; Idrissi, F-Z; Fernández-Golbano, I-M; Collette, JR; Newpher, TM; Robles, V; Lemmon, SK; Geli, M-I

Published Date

  • September 2010

Published In

Volume / Issue

  • 29 / 17

Start / End Page

  • 2899 - 2914

PubMed ID

  • 20647997

Pubmed Central ID

  • 20647997

Electronic International Standard Serial Number (EISSN)

  • 1460-2075

International Standard Serial Number (ISSN)

  • 0261-4189

Digital Object Identifier (DOI)

  • 10.1038/emboj.2010.159

Language

  • eng