Genome-wide screening for genes involved in the regulation of di-/tripeptide transport in Saccharomyces cerevisiae.
Houjian cai, Jeffrey Becker
Department of Microbiology, University of Tennessee, M407 WLS building, Knoxville, TN, 37916, USA
PTR2 encodes the transport protein Ptr2p which mediates the uptake of di-/tripeptides across the cytoplasmic membrane into the yeast Saccharomyces cerevisiae. To identify genes involved in PTR2 regulation, we performed a systematic functional screen using a haploid non-essential single gene deletion mutant library. Over 4800 deletion mutants were examined in growth assays using the dipeptide His-Leu to meet the auxotrophic requirement for leucine. 107 genes either up-regulating or down-regulating dipeptide transport were identified and confirmed. According to the gene annotation in the Yeast Proteome Database, these 107 genes represent at least eight functional categories. Twenty-eight genes are involved in the gene transcriptional regulation. Five genes are involved in the translational regulation. Nineteen genes are related to the membrane protein trafficking, translocation and internalization. Sixteen genes are related to yeast metabolism. Two genes are an ABC transporter located on the vacuole membrane and a transmembrane protein related to the uptake of leucine at low temperatures. Two genes are related to proteinase or peptidase. Thirteen genes are of unknown function, and twenty-two are others. The data provide a comprehensive picture of the molecular components required for regulating the dipeptide transport system. Further characterization of these genes will provide new insights into mechanisms regulating the expression of the di-/tripeptide membrane transporter.
Return to YGM 2004 Home at SGD