Inducible transcriptional activity of bcn-1 element from laminin gamma1-chain gene promoter in renal and nonrenal cells.
Laminin is a major component of the extracellular matrix whose expression is regulated by growth factors. The laminin gamma1-chain promoter contains a newly identified transcriptional element denoted bcn-1 that is both active and inducible in mesangial cells. In this study, we explored activation of the bcn-1 element in other renal and nonrenal cells. Treatment of rat glomerular epithelial cells (GEC) with phorbol 12-myristate 13-acetate (PMA) increased activity of the bcn-1 transcriptional element, within the context of the native laminin gamma1-chain promoter or when cloned upstream of a heterologous promoter. Treatment of GEC with PMA induced nuclear DNA-binding activity, BCN-1, which was recognized by the bcn-1 motif in a gel shift assay. These results provide evidence that the bcn-1 motif and its cognate BCN-1 factor(s) may regulate transcription of the laminin gamma1-chain in GEC. The bcn-1 element and its cognate BCN-1 DNA-binding activity were also inducible in monkey kidney COS-7 and in human T cell Jurkat lines. SDS-PAGE of in situ ultraviolet cross-linked nucleoproteins from GEC, COS, and Jurkat cells revealed one major 110-115 kDa adduct in all three cell lines. These results demonstrate that the bcn-1 element is active in renal and nonrenal cells from different mammalian species where the same protein contributes to the inducible BCN-1 DNA-binding activity.
Suzuki
H
H
Department of Medicine, University of Washington, Seattle, Washington 98195, USA.
Denisenko
O N
ON
Suzuki
Y
Y
Schullery
D S
DS
Bomsztyk
K
K
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D019556:COS Cells; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D019169:Jurkat Cells; D007678:Kidney Glomerulus / Q000187:drug effects / Q000378:metabolism*; D007797:Laminin / Q000096:biosynthesis / Q000235:genetics*; D009687:Nuclear Proteins / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic; D014162:Transfection
D004268:DNA-Binding Proteins; D007797:Laminin; D009687:Nuclear Proteins; D012333:RNA, Messenger; C089141:laminin gamma 1; D013755:Tetradecanoylphorbol Acetate