Trehalose (Tre) and glycogen (Glg) are synthesized in response to unfavorable growth conditions from glycolytic intermediates in Saccharomyces cerevisiae. Transcription of the glycolytic genes is activated by the Gcr1p complex, the DNA binding transcription factor that directly associates with the CT-box sequences on the promoter region of the glycolytic genes. gcr1 mutant yeast cells cannot utilize glucose effectively. Glg and Tre levels in stationary-phase gcr1 mutant yeast cells were 20-50 % of those in the wild-type strain. Likewise, stress-induced accumulation of Tre and Glg in gcr1 mutant cells was significantly lower than in the wild type. In addition, both the synthesis and the degradation of Tre and Glg are very slow in the gcr1 mutant. It seems that Gcr1p function is essential for the coordinated regulation of glycolysis, Tre and Glg metabolism in S. cerevisiae.