Transgenic mice demonstrate novel promoter regions for tissue-specific expression of the urokinase receptor gene

Am J Pathol. 2003 Aug;163(2):453-64. doi: 10.1016/S0002-9440(10)63675-9.

Abstract

The urokinase-type plasminogen activator receptor (u-PAR) contributes to cell migration and proteolysis in normal and cancerous tissues. Currently, there are no reports on the regulatory regions directing tissue-specific expression. Consequently, we undertook a study to identify novel promoter regions required for expression of this gene in transgenic mice bearing a LacZ reporter regulated by varying amounts (0.4, 1.5, and 8.5 kb) of upstream sequence. The 0.4-kb u-PAR upstream sequence directed weak and strong LacZ expression in the placenta and epididymis, respectively, both of which are tissues that express endogenous u-PAR. Conversely, transgene expression in the apical cells of the colon positive for endogenous u-PAR protein required 1.5 kb of upstream sequence for optimal expression. Furthermore, chromatin accessibility assays coupled with real-time polymerase chain reaction suggested a putative regulatory region spanning -1295/-1192 driving u-PAR expression in colonic cells. Interestingly, placental transgene expression was augmented with the 8.5-kb upstream fragment compared with the shorter 1.5-kb fragment indicating contributing element(s) between -1.5 and -8.5 kb. Thus, while 0.4 kb of upstream sequence directs u-PAR expression in the epididymis, sequences located between -0.4 and -1.5 kb and between -1.5 and -8.5 kb are required for optimal tissue-specific expression in the colon and the placenta, respectively.

Publication types

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

MeSH terms

  • Animals
  • Chromatin / metabolism
  • Colon / cytology
  • Colon / metabolism
  • Epididymis / cytology
  • Epididymis / metabolism
  • Female
  • Gene Expression Regulation*
  • Genes, Reporter
  • Male
  • Mice
  • Mice, Transgenic
  • Placenta / cytology
  • Placenta / metabolism
  • Plasminogen Activators / genetics*
  • Plasminogen Activators / metabolism
  • Promoter Regions, Genetic*
  • Receptors, Cell Surface / genetics*
  • Receptors, Cell Surface / metabolism
  • Receptors, Urokinase Plasminogen Activator
  • Tissue Distribution

Substances

  • Chromatin
  • Plaur protein, mouse
  • Receptors, Cell Surface
  • Receptors, Urokinase Plasminogen Activator
  • Plasminogen Activators