Abstract
Serine dehydratase (SDH), which is involved in gluconeogenesis, is induced in adult liver under diabetic conditions and by high protein diet. Its expression is inhibited in rapidly growing, immature liver such as fetal or regenerating liver. The molecular mechanisms of regulation of its expression in various conditions were investigated. Results indicated that in fetal rat liver, transcription of the SDH gene is repressed by a negative trans-acting factor(s), which may decrease or be inactivated during terminal differentiation of hepatocytes. On the oontnury, the decrease in its expression in regenerating liver seemed to be caused by decrease of positive trans-acting factors. The rat SDH gene contains glucocorticoid- and cAMP- responsive e|ements, but the mechanism of the synergistic effects of glucocorticoid and glucagon (cAMP) on enzyme induction is unknown.
