Regulation of endosomal clathrin and retromer-mediated endosome to Golgi retrograde transport by the J-domain protein RME-8

EMBO J. 2009 Nov 4;28(21):3290-302. doi: 10.1038/emboj.2009.272. Epub 2009 Sep 17.

Abstract

After endocytosis, most cargo enters the pleiomorphic early endosomes in which sorting occurs. As endosomes mature, transmembrane cargo can be sequestered into inwardly budding vesicles for degradation, or can exit the endosome in membrane tubules for recycling to the plasma membrane, the recycling endosome, or the Golgi apparatus. Endosome to Golgi transport requires the retromer complex. Without retromer, recycling cargo such as the MIG-14/Wntless protein aberrantly enters the degradative pathway and is depleted from the Golgi. Endosome-associated clathrin also affects the recycling of retrograde cargo and has been shown to function in the formation of endosomal subdomains. Here, we find that the Caemorhabditis elegans endosomal J-domain protein RME-8 associates with the retromer component SNX-1. Loss of SNX-1, RME-8, or the clathrin chaperone Hsc70/HSP-1 leads to over-accumulation of endosomal clathrin, reduced clathrin dynamics, and missorting of MIG-14 to the lysosome. Our results indicate a mechanism, whereby retromer can regulate endosomal clathrin dynamics through RME-8 and Hsc70, promoting the sorting of recycling cargo into the retrograde pathway.

Publication types

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

MeSH terms

  • Animals
  • Caenorhabditis elegans / cytology*
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / analysis
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Carrier Proteins / analysis
  • Carrier Proteins / metabolism
  • Cell Line
  • Cell Polarity
  • Clathrin / metabolism*
  • Endosomes / metabolism*
  • Golgi Apparatus / genetics
  • HSC70 Heat-Shock Proteins / metabolism
  • Intracellular Signaling Peptides and Proteins
  • Lysosomes / metabolism
  • Mutation
  • Neurons / cytology
  • Sorting Nexins
  • Vesicular Transport Proteins / analysis
  • Vesicular Transport Proteins / genetics
  • Vesicular Transport Proteins / metabolism*

Substances

  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • Clathrin
  • HSC70 Heat-Shock Proteins
  • Intracellular Signaling Peptides and Proteins
  • Mig-14 protein, C elegans
  • RME-8 protein, C elegans
  • SNX-1 protein, C elegans
  • Sorting Nexins
  • Vesicular Transport Proteins