Glucose should not be considered uniquely as a cellular fuel but also as a signaling molecule involved in the regulation of genes encoding glycolytic and lipogenic enzymes and, as such, in storage of triglycerides. Transcriptional effects of glucose on glycolytic and lipogenic enzymes involve a specific transcription factor, ChREBP, whose characteristics and mechanism of activation are described. Finally, the possible implication of ChREBP in the physiopathology of obesity and type 2 diabetes are discussed.