Unknown,Transcriptomics,Genomics,Proteomics

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Transcription profiling of wild type, GALT-deficient and GALT-deficient-revertant yeast grown on media with galactose or glucose

ABSTRACT: To better understand the pathophysiology of galactose-1-phosphate uridyltransferase (GALT) deficiency in humans, we studied the mechanisms by which a GALT-deficient yeast survived on galactose medium. Under normal conditions, GALT-deficient yeast cannot grow in medium that contains 0.2% galactose as the sole carbohydrate, a phenotype of Gal(-). We isolated revertants from a GALT-deficient yeast by direct selection for growth in galactose, a phenotype of Gal(+). Comparison of gene expression profiles among wild-type and revertant strains on galactose medium revealed that the revertant down-regulated genes encoding enzymes including galactokinase, galactose permease, and UDP-galactose-4-epimerase (the GAL regulon). By contrast, the revertant strain up-regulated the gene for UDP-glucose pyrophosphorylase, UGP1. There was reduced accumulation of galactose-1-phosphate in the galactose-grown revertant cells when compared to the GALT-deficient parent cells.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Maria Klapa

PROVIDER: E-MEXP-1420 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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