Molecular characterization of a novel transcription factor that controls stromelysin expression

Mol Cell Biol. 1995 Jun;15(6):3164-70. doi: 10.1128/MCB.15.6.3164.

Abstract

Stromelysins, which are the metalloproteinases with the widest substrate specificities, play a critical role in tumor invasion and metastasis. We have previously reported an element (SPRE) of the stromelysin promoter located between nucleotides -1221 and -1203 that is necessary and sufficient for the control of stromelysin gene expression by mitogenic activation, which induces a nuclear activity that binds to this sequence. Using a concatenated probe with several copies of this element to screen a lambda gt11 cDNA expression library from mouse Swiss 3T3 fibroblasts, we report here the molecular cloning of a cDNA coding for a novel protein (SPBP) of 937 amino acids that binds to this element and has several features of a transcription factor, such as a putative leucine zipper region, a nuclear localization signal, and a basic domain with homology to the DNA-binding domains of Fos and Jun. Evidence that SPBP is at least a critical component of the mitogen-induced SPRE nuclear binding activity is presented here. Furthermore, the transfection of an expression plasmid for SPBP transactivates reporter chloramphenicol acetyltransferase plasmids containing either the full-length stromelysin promoter or a single copy of the SPRE cloned upstream of the herpes simplex virus thymidine kinase minimal promoter. Therefore, the results presented here identify a novel transcription factor critically involved in the control of stromelysin expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary
  • Gene Expression Regulation, Enzymologic
  • Matrix Metalloproteinase 3
  • Metalloendopeptidases / biosynthesis*
  • Metalloendopeptidases / genetics
  • Mice
  • Molecular Sequence Data
  • Transcription Factors / chemistry
  • Transcription Factors / genetics*
  • Transcription Factors / isolation & purification

Substances

  • DNA, Complementary
  • Transcription Factors
  • Metalloendopeptidases
  • Matrix Metalloproteinase 3

Associated data

  • GENBANK/U20282