Rgt1p of Saccharomyces cerevisiae, a key regulator of glucose-induced genes, is both an activator and a repressor of transcription.

摘要: The RGT1 gene of Saccharomyces cerevisiae plays a central role in the glucose-induced expression hexose transporter (HXT) genes. Genetic evidence suggests that it encodes repressor HXT genes whose function is inhibited by glucose. Here, we report isolation and demonstrate bifunctional transcription factor. Rgt1p displays three different transcriptional modes response to glucose: (i) absence glucose, functions as repressor; (ii) high concentrations glucose cause activator; (iii) cells growing on low levels has neutral role, neither repressing nor activating transcription. Glucose alters through pathway includes two sensors, Snf3p Rgt2p, Grr1p. Snf3p, which appears be low-glucose sensor, required for inhibition high-glucose conversion into an activator Grr1p, component signaling pathway, both inactivation at Thus, signals generated sensors act Grr1p determine function.