Novel function of clathrin light chain in promoting endocytic vesicle formation

Mol Biol Cell. 2006 Oct;17(10):4343-52. doi: 10.1091/mbc.e06-07-0606. Epub 2006 Jul 26.

Abstract

Clathrin-mediated endocytosis is a major pathway for uptake of lipid and protein cargo at the plasma membrane. The lattices of clathrin-coated pits and vesicles are comprised of triskelions, each consisting of three oligomerized heavy chains (HC) bound by a light chain (LC). In addition to binding HC, LC interacts with members of the Hip1/R family of endocytic proteins, including the budding yeast homologue, Sla2p. Here, using in vivo analysis in yeast, we provide novel insight into the role of this interaction. We find that overexpression of LC partially restores endocytosis to cells lacking clathrin HC. This suppression is dependent on the Sla2p binding region of LC. Using live cell imaging techniques to visualize endocytic vesicle formation, we find that the N-terminal Sla2p binding region of LC promotes the progression of arrested Sla2p patches that form in the absence of HC. We propose that LC binding to Sla2p positively regulates Sla2p for efficient endocytic vesicle formation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Carrier Proteins / metabolism*
  • Clathrin Heavy Chains / genetics
  • Clathrin Light Chains / genetics
  • Clathrin Light Chains / physiology*
  • Clathrin-Coated Vesicles / physiology
  • Cytoskeletal Proteins
  • Models, Biological
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Saccharomyces cerevisiae Proteins / physiology*
  • Transport Vesicles / physiology*

Substances

  • Carrier Proteins
  • Clathrin Light Chains
  • Cytoskeletal Proteins
  • SLA2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Clathrin Heavy Chains