ABSTRACT
In the yeast Saccharomyces cerevisiae, hydrostatic pressure at 25 MPa is known to be nonlethal but significantly impairs the uptake of tryptophan by the permease Tat2, thereby inhibiting the growth of strains that require tryptophan from the medium. Here, we found that the lack of the YPR153W gene, so far poorly characterized for its role in yeast, caused a serious adverse effect on the growth at 10–25 MPa in the strain that required tryptophan. Deletion for YPR153W resulted in an increased rate of pressure-induced degradation of Tat2, suggesting that Tat2 is destabilized in the YPR153W deletion mutant at 25 MPa. Overexpression of the TAT2 gene enabled the deletion mutant to grow at 25 MPa. These results suggest that Ypr153w is essential for the stability and proper transport function of Tat2 under pressure at 10–25 MPa.
ABBREVIATIONS: Trp+: the phenotype of tryptophan prototrophic strains that synthesize tryptophan de novo; Trp−: the phenotype of tryptophan auxotrophic strains that require tryptophan from the medium; YPR153W: an yeast poorly characterized gene; Ypr153w: a protein encoded by the YPR153W gene; ypr153wΔ: a deletion mutant for the YPR153W gene; Tat2: the high-affinity tryptophan permease; MCT10: a human aromatic amino acid transporter
Acknowledgements
We thank Satoshi Uemura, Takahiro Mochizuki and Yuri Kozaki for technical assistances, and Yoichi Noda and Akira Matsuura for useful discussions.
Disclosure statement
No potential conflict of interest was reported by the authors.