CytLEK1 is a regulator of plasma membrane recycling through its interaction with SNAP-25

Mol Biol Cell. 2006 Jul;17(7):3176-86. doi: 10.1091/mbc.e05-12-1127. Epub 2006 May 3.

Abstract

SNAP-25 is a component of the SNARE complex that is involved in membrane docking and fusion. Using a yeast two-hybrid screen, we identify a novel interaction between SNAP-25 and cytoplasmic Lek1 (cytLEK1), a protein previously demonstrated to associate with the microtubule network. The binding domains within each protein were defined by yeast two-hybrid, coimmunoprecipitation, and colocalization studies. Confocal analyses reveal a high degree of colocalization between the proteins. In addition, the endogenous proteins can be isolated as a complex by immunoprecipitation. Further analyses demonstrate that cytLEK1 and SNAP-25 colocalize and coprecipitate with Rab11a, myosin Vb, VAMP2, and syntaxin 4, components of the plasma membrane recycling pathway. Overexpression of the SNAP-25-binding domain of cytLEK1, and depletion of endogenous Lek1 alters transferrin trafficking, consistent with a function in vesicle recycling. Taken together, our studies indicate that cytLEK1 is a link between recycling vesicles and the microtubule network through its association with SNAP-25. This interaction may play a key role in the regulation of the recycling endosome pathway.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Membrane / chemistry
  • Cell Membrane / metabolism*
  • Cells, Cultured
  • Chromosomal Proteins, Non-Histone / analysis
  • Chromosomal Proteins, Non-Histone / metabolism*
  • Endosomes / chemistry
  • Endosomes / metabolism
  • Mice
  • Microfilament Proteins
  • Microtubules / metabolism
  • Protein Interaction Mapping
  • Protein Structure, Tertiary
  • Protein Transport
  • Sequence Deletion
  • Synaptosomal-Associated Protein 25 / analysis
  • Synaptosomal-Associated Protein 25 / metabolism*
  • Transferrin / metabolism
  • Two-Hybrid System Techniques

Substances

  • Chromosomal Proteins, Non-Histone
  • Microfilament Proteins
  • Synaptosomal-Associated Protein 25
  • Transferrin
  • centromere protein F