Fig. 1. Composition and regulation of the glycolytic pathway in higher animals. (A) Linear pathway of glycolytic enzymes showing substrate input and sites of ATP utilization and generation. (B) Induction of glycolytic enzyme mRNA levels by hypoxia. Skeletal myocytes were exposed to hypoxia and mRNA transcript levels were measured at the indicated time points by the nuclear run-on technique, described in Webster (1987). The figure is a composite of six glycolytic enzyme gene transcripts using cDNAs to the enzymes indicated by the asterisks in A.