Regulation of hormonal induction of chick liver cytosol-specific phosphoenolpyruvate carboxykinase.
Administration of glucagon, epinephrine, or dibutyryl cAMP to chicks induced cytosol-specific phosphoenolpyruvate carboxykinase in liver. In vitro translation assay with poly(A)+RNA indicated that this induction was due to the increase in phosphoenolpyruvate carboxykinase-coding mRNA synthesis which resulted from an increased level of hepatic cAMP. Either hydrocortisone or alpha-adrenergic agonist was ineffective for the induction by itself, but showed a significant effect when administered together with one of the inducing agents given above. In particular, hydrocortisone enhanced the synthesis of phosphoenolpyruvate carboxykinase-specific mRNA without changing the profile of the time courses of the induction and of hepatic cAMP level. Those observations suggest that the fundamental machinery required for induction of cytosol-specific phosphoenolpyruvate carboxykinase in liver is shared in common between rat and chick, and that the absence of appreciable induction of cytosol-specific hepatic phosphoenolpyruvate carboxykinase in starved chicks is due to neither lack nor impairment of the hormone-mediated induction mechanism, but is due to the difference in usage of the genetic information between the two animal species.
Sato
A
A
Department of Biochemistry, Fukushima Medical College.
Suzuki
T
T
Kochi
H
H
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002645:Chickens; D003513:Cycloheximide / Q000494:pharmacology; D003600:Cytosol / Q000201:enzymology; D004790:Enzyme Induction / Q000187:drug effects; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D005934:Glucagon / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology*; D006854:Hydrocortisone / Q000494:pharmacology; D008930:Mitochondria, Liver / Q000187:drug effects / Q000201:enzymology*; D010729:Phosphoenolpyruvate Carboxykinase (GTP) / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism
D006728:Hormones; D012333:RNA, Messenger; D003994:Bucladesine; D005934:Glucagon; D003513:Cycloheximide; D010729:Phosphoenolpyruvate Carboxykinase (GTP); D006854:Hydrocortisone; D004837:Epinephrine