A haploid genetic screen identifies the major facilitator domain containing 2A (MFSD2A) transporter as a key mediator in the response to tunicamycin.

Proc Natl Acad Sci U S A
Authors
Keywords
Abstract

Tunicamycin (TM) inhibits eukaryotic asparagine-linked glycosylation, protein palmitoylation, ganglioside production, proteoglycan synthesis, 3-hydroxy-3-methylglutaryl coenzyme-A reductase activity, and cell wall biosynthesis in bacteria. Treatment of cells with TM elicits endoplasmic reticulum stress and activates the unfolded protein response. Although widely used in laboratory settings for many years, it is unknown how TM enters cells. Here, we identify in an unbiased genetic screen a transporter of the major facilitator superfamily, major facilitator domain containing 2A (MFSD2A), as a critical mediator of TM toxicity. Cells without MFSD2A are TM-resistant, whereas MFSD2A-overexpressing cells are hypersensitive. Hypersensitivity is associated with increased cellular TM uptake concomitant with an enhanced endoplasmic reticulum stress response. Furthermore, MFSD2A mutant analysis reveals an important function of the C terminus for correct intracellular localization and protein stability, and it identifies transmembrane helical amino acid residues essential for mediating TM sensitivity. Overall, our data uncover a critical role for MFSD2A by acting as a putative TM transporter at the plasma membrane.

Year of Publication
2011
Journal
Proc Natl Acad Sci U S A
Volume
108
Issue
29
Pages
11756-65
Date Published
2011 Jul 19
ISSN
1091-6490
URL
DOI
10.1073/pnas.1018098108
PubMed ID
21677192
PubMed Central ID
PMC3141996
Links
Grant list
R01 CA103866 / CA / NCI NIH HHS / United States
R21 HG004938 / HG / NHGRI NIH HHS / United States
CA103866 / CA / NCI NIH HHS / United States
Howard Hughes Medical Institute / United States
CA129105 / CA / NCI NIH HHS / United States
R01 CA129105 / CA / NCI NIH HHS / United States
R21 HG004938-01 / HG / NHGRI NIH HHS / United States