English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Intracellular trafficking of the general amino acid permease, Gap1p, of Saccharomyces cerevisiae is regulated by amino acid abundance. When amino acids are scarce Gap1p is sorted to the plasma membrane, whereas when amino acids are abundant Gap1p is sorted from the trans-Golgi through the multivesicular endosome (MVE) and to the vacuole. Here we test the hypothesis that Gap1p itself is the sensor of amino acid abundance by examining the trafficking of Gap1p mutants with altered substrate specificity and transport activity. We show that trafficking of mutant Gap1p(A297V), which does not transport basic amino acids, is also not regulated by these amino acids. Furthermore, we have identified a catalytically inactive mutant that does not respond to complex amino acid mixtures and constitutively sorts Gap1p to the plasma membrane. Previously we showed that amino acids govern the propensity of Gap1p to recycle from the MVE to the plasma membrane. Here we propose that in the presence of substrate the steady-state conformation of Gap1p shifts to a state that is unable to be recycled from the MVE. These results indicate a parsimonious regulatory mechanism by which Gap1p senses its transport substrates to set an appropriate level of transporter activity at the cell surface.

Transport activity–dependent intracellular sorting of the yeast general amino acid permease