Post-transcriptional regulation of ura4+ gene expression by glucose in Schizosaccharomyces pombe.

Glucose-inducible gene expression is a fundamental cellular response for optimal cell growth, but identities of glucose-inducible genes and its regulatory mechanism remain largely elusive in Schizosaccharomyces pombe. Here we report that ura4+, encoding orotidine monophosphate decarboxylase (OMPdecase), shows glucose-inducible expression regulated at post-transcriptional level. The ura4+ mRNA level was rapidly decreased by approximately 50% within 20 min after glucose depletion and it was readily recovered upon glucose-readdition within 1 h. Glucose at above 2% similarly raised the transcript level of ura4+, while low concentration (0.1%) was not effective. Interestingly, control of mRNA turnover would be the main regulatory step of the glucose-dependent expression of ura4+. Moreover, stress-activated MAPK (SAPK) pathway was partially responsible for the glucose-regulated expression of ura4+ and rrg1+, another example of glucose-dependent mRNA stability control in S. pombe. These results suggest that the SAPK pathway might participate in the glucose-dependent regulation of ura4+ and rrg1+ mRNA stabilities.