Sequence of the 5′-flanking region of the rat 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase gene: Regulation by glucocorticoids

Dexamethasone addition to cultured hepatocytes caused a 90-fold increase in mRNA for 6-phosphofructo 2-kinase/fructose-2, 6-bisphosphatase. Glucocorticoid administration in vivo also increased the enzyme's mRNA in skeletal muscle by 3-4-fold. The sequence of the 5′-flanking region of the enzyme's gene revealed at least one consensus glucocorticoid response element. The amino acid sequence derived from a partial cDNA clone for the rat skeletal muscle bifunctional enzyme was identical to that of the liver isozyme except for an undetermined amount of N-terminal sequence. It is concluded that the rat muscle and liver isozymes, which are postulated to be identical except for the N-terminal region, are both regulated by glucocorticoids.