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bioRxiv · 10.1101/2020.04.24.059832

Complementary α-arrestin - Rsp5 ubiquitin ligase complexes control selective nutrient transporter endocytosis in response to amino acid availability

Ivashov, V.·Zimmer, J.·Schmidt, O.·Teis, D.
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Abstract

How cells adjust transport across their membranes is incompletely understood. Previously, we have shown that S.cerevisiae broadly re-configures the nutrient transporters at the plasma membrane in response to amino acid availability, through selective endocytosis of sugar- and amino acid transporters (AATs) (Muller et al., 2015). A genome-wide screen now revealed that Art2/Ecm21, a member of the -arrestin family of Rsp5 ubiquitin ligase adaptors, is required for the simultaneous endocytosis of four AATs and induced during starvation by the general amino acid control pathway. Art2 uses a basic patch to recognize C-terminal acidic sorting motifs in these AATs and instructs Rsp5 to ubiquitinate proximal lysine residues. In response to amino acid excess, Rsp5 instead uses TORC1-activated Art1 to detect N-terminal acidic sorting motifs within the same AATs, which initiates exclusive substrate-induced endocytosis of individual AATs. Thus, amino acid availability activates complementary -arrestin-Rsp5-complexes to control selective endocytosis for nutrient acquisition.

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Ivashov, V., Zimmer, J., Schmidt, O., Teis, D.. 2020-04-25. Complementary α-arrestin - Rsp5 ubiquitin ligase complexes control selective nutrient transporter endocytosis in response to amino acid availability. https://doi.org/10.1101/2020.04.24.059832

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