Abstract
We previously demonstrated that, in hepatocytes in primary culture, the role of insulin on induction of L-type pyruvate kinase (L-PK) gene expression was mainly to induce glucokinase synthesis, needed for glucose phosphorylation to glucose 6-phosphate. However, we show here that when hepatocytes have been isolated from rats starved for 72 h, glucose and constitutive glucokinase expression was not sufficient to fully stimulate the L-PR promoter, low insulin concentrations being still required. In addition, activation remains sensitive to cAMP inhibition, but cannot he reproduced in the absence of insulin by a competitive cAMP antagonist. We propose that both insulin and cAMP act on expression of the L-PK gene at, at least, two levels: positive and negative regulation of glucokinase gene expression, and more downstream levels.
Original language | English (US) |
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Pages (from-to) | 81-84 |
Number of pages | 4 |
Journal | FEBS Letters |
Volume | 417 |
Issue number | 1 |
DOIs | |
State | Published - Nov 3 1997 |
Externally published | Yes |
Keywords
- Cyclic AMP
- Glucose
- Insulin
- L-type pyruvate kinase
- Transcriptional control
ASJC Scopus subject areas
- Genetics
- Molecular Biology
- Biophysics
- Structural Biology
- Biochemistry
- Cell Biology