Differential physiological roles of ESCRT complexes in Caenorhabditis elegans

Mol Cells. 2011 Jun;31(6):585-92. doi: 10.1007/s10059-011-1045-z. Epub 2011 Jun 10.

Abstract

Endosomal sorting complex required for transport (ESCRT) complexes are involved in endosomal trafficking to the lysosome, cytokinesis, and viral budding. Extensive genetic, biochemical, and structural studies on the ESCRT system have been carried out in yeast and mammalian systems. However, the question of how the ESCRT system functions at the whole organism level has not been fully explored. In C. elegans, we performed RNAi experiments to knock-down gene expression of components of the ESCRT system and profiled their effects on protein degradation and endocytosis of YP170, a yolk protein. Targeted RNAi knock-down of ESCRT-I (tsg-101 and vps-28) and ESCRT-III (vps-24, and vps-32.2) components interfered with protein degradation while knock-down of ESCRT-II (vps-25 and vps-36) and ESCRT-III (vps-20 and vps-24) components hampered endocytosis. In contrast, the knockdown of vps-37, another ESCRT-I component, showed no defect in either YP170 uptake or degradation. Depletion of at least one component from each complex - ESCRT-0 (hgrs-1), ESCRT-I (tsg-101, vps-28, and vps-37), ESCRT-II (vps-36), ESCRT-III (vps-24), and Vps4 (vps-4) - resulted in abnormal distribution of embryos in the uterus of worms, possibly due to abnormal ovulation, fertilization, and egglaying. These results suggest differential physiological roles of ESCRT-0, -I, -II, and -III complexes in the context of the whole organism, C. elegans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / embryology
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / physiology*
  • Egg Proteins / metabolism
  • Endocytosis
  • Endosomal Sorting Complexes Required for Transport / genetics
  • Endosomal Sorting Complexes Required for Transport / physiology*
  • Endosomes / metabolism
  • Lysosomes / metabolism
  • Protein Transport / genetics
  • RNA Interference

Substances

  • Caenorhabditis elegans Proteins
  • Egg Proteins
  • Endosomal Sorting Complexes Required for Transport