Inducible transcriptional activity of bcn-1 element from laminin gamma1-chain gene promoter in renal and nonrenal cells

Am J Physiol. 1998 Oct;275(4):F518-26. doi: 10.1152/ajprenal.1998.275.4.F518.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Binding Sites
  • COS Cells
  • Cell Nucleus / metabolism
  • Cloning, Molecular
  • Conserved Sequence
  • DNA-Binding Proteins / metabolism*
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism
  • Humans
  • Jurkat Cells
  • Kidney Glomerulus / drug effects
  • Kidney Glomerulus / metabolism*
  • Laminin / biosynthesis
  • Laminin / genetics*
  • Nuclear Proteins / metabolism*
  • Promoter Regions, Genetic*
  • RNA, Messenger / metabolism
  • Rats
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transcription, Genetic*
  • Transfection

Substances

  • DNA-Binding Proteins
  • Laminin
  • Nuclear Proteins
  • RNA, Messenger
  • laminin gamma 1
  • Tetradecanoylphorbol Acetate