Factors involved in the regulation of the Schizosaccharomyces pombe malic enzyme gene

Transcription of the Schizosaccharomyces pombe malic enzyme gene, mae2, is induced when cells are grown on high glucose concentrations or under nonaer ated conditions. Two cis-acting elements in the mae2 promoter, upstream act ivator sequences UAS1 and UAS2, are required for basal expression, whilst t hree negative-acting. upstream repressor sequences are involved in general derepression of mae2. Both the Pka1 and Sty1 signal transduction pathways a re involved in the induced expression of mae2 under fermentative conditions . Expression of mae2 seems to be regulated in response to the carbon source , lack of oxygen and osmotic stress conditions, probably to assist in maint aining the intracellular redox balance.