Integrated control of transporter endocytosis and recycling by the arrestin-related protein Rod1 and the ubiquitin ligase Rsp5

Elife. 2014 Nov 7;3:e03307. doi: 10.7554/eLife.03307.

Abstract

After endocytosis, membrane proteins can recycle to the cell membrane or be degraded in lysosomes. Cargo ubiquitylation favors their lysosomal targeting and can be regulated by external signals, but the mechanism is ill-defined. Here, we studied the post-endocytic trafficking of Jen1, a yeast monocarboxylate transporter, using microfluidics-assisted live-cell imaging. We show that the ubiquitin ligase Rsp5 and the glucose-regulated arrestin-related trafficking adaptors (ART) protein Rod1, involved in the glucose-induced internalization of Jen1, are also required for the post-endocytic sorting of Jen1 to the yeast lysosome. This new step takes place at the trans-Golgi network (TGN), where Rod1 localizes dynamically upon triggering endocytosis. Indeed, transporter trafficking to the TGN after internalization is required for their degradation. Glucose removal promotes Rod1 relocalization to the cytosol and Jen1 deubiquitylation, allowing transporter recycling when the signal is only transient. Therefore, nutrient availability regulates transporter fate through the localization of the ART/Rsp5 ubiquitylation complex at the TGN.

Keywords: S. cerevisiae; arrestin-related proteins; cell biology; endocytosis; glucose signaling; transporter; ubiquitin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arrestin / metabolism*
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism
  • Cytosol / drug effects
  • Cytosol / metabolism
  • Endocytosis* / drug effects
  • Endosomal Sorting Complexes Required for Transport / metabolism*
  • Glucose / pharmacology
  • Green Fluorescent Proteins
  • Membrane Proteins / metabolism*
  • Models, Biological
  • Saccharomyces cerevisiae / cytology*
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Secretory Pathway / drug effects
  • Ubiquitin / metabolism*
  • Ubiquitin-Protein Ligase Complexes / metabolism*
  • Ubiquitination / drug effects
  • Vacuoles / drug effects
  • Vacuoles / metabolism
  • trans-Golgi Network / drug effects
  • trans-Golgi Network / metabolism

Substances

  • Arrestin
  • Endosomal Sorting Complexes Required for Transport
  • Membrane Proteins
  • ROD1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Ubiquitin
  • Green Fluorescent Proteins
  • Ubiquitin-Protein Ligase Complexes
  • RSP5 protein, S cerevisiae
  • Glucose

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.