Positive and negative elements modulate the promoter of the human liver-specific alpha2-HS-glycoprotein gene.
The human alpha2-HS-glycoprotein (AHSG) and the 63-kDa rat phosphoprotein (pp63) are homologous plasma proteins that belong to the fetuin family. AHSG and pp63 are involved in important functions such as inhibition of insulin receptor tyrosine kinase activity, inhibition of protease activities, and regulation of calcium metabolism and osteogenesis. Studies of the AHSG proximal promoter performed in vitro in rat and human cells indicate that several NF-1 and C/EBP binding sites exert a positive effect on its transcriptional activity. However, until now, no distal elements have been examined in this gene, in either species. We report that the human AHSG gene promoter acts in a liver-specific manner and is further controlled by three distal, 5'-flanking elements. The negative elements III and I are, respectively, located 5' and 3' of the positive element II. All three elements require the natural context of the human AHSG gene to fully exert their negative or positive effect. Element I harbours a single binding site for NF-1. This nuclear factor thus appears to be able to up- or downregulate the AHSG gene depending on the site it binds to. Elements I, II and possibly III are absent in the rodent Ahsg gene encoding pp63.
Banine
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F
INSERM Unit-519, Faculté de Médecine-Pharmacie, Institut Fédératif de Recherches Multidisciplinaires sur les Peptides, Rouen, France.
Gangneux
C
C
Mercier
L
L
Le Cam
A
A
Salier
J P
JP
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D001798:Blood Proteins / Q000235:genetics*; D016466:CHO Cells; D006224:Cricetinae; D015342:DNA Probes / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D008099:Liver / Q000166:cytology; D051839:NFI Transcription Factors; D009928:Organ Specificity; D011401:Promoter Regions, Genetic / Q000235:genetics*; D051381:Rats; D012097:Repressor Proteins / Q000378:metabolism*; D020218:Response Elements / Q000235:genetics; D017384:Sequence Deletion / Q000235:genetics; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D014407:Tumor Cells, Cultured; D060749:alpha-2-HS-Glycoprotein
C556354:AHSG protein, human; C071388:Ahsg protein, rat; D001798:Blood Proteins; D015342:DNA Probes; D004268:DNA-Binding Proteins; D006023:Glycoproteins; D051839:NFI Transcription Factors; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D060749:alpha-2-HS-Glycoprotein; C080333:transcription factor nuclear factor 1