Growth hormone induction of hepatic serine protease inhibitor 2.1 transcription is mediated by a Stat5-related factor binding synergistically to two gamma-activated sites.
A growth hormone (GH)-inducible nuclear factor (GHINF) from rat liver has been purified to near homogeneity. On SDS-polyacrylamide gel electrophoresis and UV-cross-linking, a major band of mass approximately 93 kDa and a minor band of approximately 70 kDa are detected in the purified fraction. DNase I footprinting using purified GHINF yields a protected region of -149/-115 on the rat serine protease inhibitor 2.1 (Spi 2.1) promoter encompassed within the growth hormone response element (GHRE). Mutational analysis demonstrated that GHINF binds synergistically to two gamma-interferon-activated sites (GAS) within the GHRE, with the 3' element being the pivotal binding domain. Functional assays show that both GAS elements are necessary for full GH response. GHINF has no immunoreactivity with either a C-terminal Stat1 antibody or an N-terminal Stat3 antibody, while cross-reacting with a C-terminal Stat5 monoclonal antibody. GHINF will bind to two GAS elements from the Stat5 binding region of the beta-casein gene. These studies indicate that GHINF is a Stat5-related factor binding synergistically to two GAS elements to activate Spi 2.1 transcription.
Bergad
P L
PL
Department of Pediatrics, University of Minnesota, Minneapolis 55455, USA.
Shih
H M
HM
Towle
H C
HC
Schwarzenberg
S J
SJ
Berry
S A
SA
D000818:Animals; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000502:physiology*; D013006:Growth Hormone / Q000494:pharmacology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism; D008894:Milk Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D050794:STAT1 Transcription Factor; D050799:STAT5 Transcription Factor; D015842:Serine Proteinase Inhibitors / Q000235:genetics*; D015534:Trans-Activators / Q000502:physiology*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D008894:Milk Proteins; D009687:Nuclear Proteins; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D050799:STAT5 Transcription Factor; D015842:Serine Proteinase Inhibitors; C494081:Stat1 protein, rat; D015534:Trans-Activators; D007371:Interferon-gamma; D013006:Growth Hormone