z-logo
open-access-imgOpen Access
A Chemical Genetic Screen for Modulators of Exocytic Transport Identifies Inhibitors of a Transport Mechanism Linked to GTR2 Function
Author(s) -
Lisha Zhang,
Min Huang,
Edina Harsay
Publication year - 2010
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.00184-09
Subject(s) - genetic screen , biology , microbiology and biotechnology , mutant , golgi apparatus , phenotype , small gtpase , transport protein , secretory pathway , saccharomyces cerevisiae , gene , genetics , signal transduction , endoplasmic reticulum
Membrane and protein traffic to the cell surface is mediated by partially redundant pathways that are difficult to perturb in ways that yield a strong phenotype. Such robustness is expected in a fine-tuned process, regulated by environmental cues, that is required for controlled cell surface growth and cell proliferation. Synthetic genetic interaction screens are especially valuable for investigating complex processes involving partially redundant pathways or mechanisms. In a previous study, we used a triple-synthetic-lethal yeast mutant screen to identify a novel component of the late exocytic transport machinery, Avl9. In a chemical-genetic version of the successful mutant screen, we have now identified small molecules that cause a rapid (within 15 min) accumulation of secretory cargo and abnormal Golgi compartment-like membranes at low concentration (<2 μM), indicating that the compounds likely target the exocytic transport machinery at the Golgi. We screened for genes that, when overexpressed, suppress the drug effects, and found that the Ras-like small GTPase, Gtr2, but not its homolog and binding partner, Gtr1, efficiently suppresses the toxic effects of the compounds. Furthermore, assays for suppression of the secretory defect caused by the compounds suggest that Gtr proteins can regulate a pathway that is perturbed by the compounds. Becauseavl9Δ andgtr mutants share some phenotypes, our results indicate that the small molecules identified by our chemical-genetic strategy are promising tools for understanding Avl9 function and the mechanisms that control late exocytic transport.

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here