title: Control of gene expression by growth hormone in liver: key role of a network of transcription factors.
abstract: Growth hormone (GH) controls gene expression in liver. Recent work suggests that this can result in part from the stimulation by GH of the synthesis of liver-specific transcription factors, one of which is HNF-6. The liver-specific factors HNF-4 and C/EBP alpha respectively stimulate and inhibit transcription of the hnf 6 gene. Upon GH stimulation, the affinity of HNF-4 for the hnf 6 promoter is increased and the binding of C/EBP alpha is decreased. GH therefore controls hnf 6 by a combination of stimulatory and derepressive mechanisms. On the other hand, HNF-6 stimulates transcription of the hnf 3beta and hnf 4 genes, the stimulation of hnf 4 resulting most likely from the GH-induced increase in HNF-6 concentration. We conclude that in liver GH is likely to control the synthesis of a whole set of proteins whose genes are regulated by a GH-sensitive network of transcription factors, which regulate each other by feed-back and autoregulatory loops.
authors.affiliation: Hormone and Metabolic Research Unit, University catholique de Louvain and Christian de Duve Institute of Cellular Pathology, Brussels, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Rastegar
authors.forename: F P
authors.initials: FP
authors.lastname: Lemaigre
authors.forename: G G
authors.initials: GG
authors.lastname: Rousseau
mesh_terms: D000818:Animals; D005786:Gene Expression Regulation / Q000502:physiology*; D013006:Growth Hormone / Q000502:physiology*; D006801:Humans; D008099:Liver / Q000502:physiology*
chemical_list: D013006:Growth Hormone