An AU-rich sequence in the 3'-UTR of plasminogen activator inhibitor type 2 (PAI-2) mRNA promotes PAI-2 mRNA decay and provides a binding site for nuclear HuR

Nucleic Acids Res. 1999 Apr 1;27(7):1664-73. doi: 10.1093/nar/27.7.1664.

Abstract

The plasminogen activator inhibitor type 2 (PAI-2) gene is regulated by transcriptional and post-transcriptional processes. We have previously shown that insertion of the 3'-untranslated region (3'-UTR) of PAI-2 mRNA into the 3'-UTR of a beta-globin reporter mRNA reduces constitutive beta-globin mRNA expression and that this requires, at least in part, an AU-rich motif. Here we have directly assessed the role of this motif in PAI-2 mRNA stability using both chimeric and non-chimeric reporter systems. We first show that the full-length PAI-2 mRNA is indeed unstable with a half-life of 1 h. Using the c-fos promoter-driven human growth hormone (HGH) mRNA as a reporter, we demonstrate that the 580 nt 3'-UTR of PAI-2 accelerates chimeric HGH mRNA decay in a process which is dependent on the intact AU-rich sequence. Furthermore, disruption of this motif within a constitutively expressed PAI-2 cDNA produces a 2.5- and 2. 7-fold increase in PAI-2 mRNA and protein levels in HT-1080 cells, respectively. RNA electrophoretic mobility shift and supershift assays indicate that this motif provides a specific binding site for cellular proteins that include nuclear HuR. Taken together, these data show that a correlation exists between the binding of HuR to the AU-rich motif in vitro and the destabilizing properties conferred by this sequence in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • 3T3 Cells
  • Animals
  • Antigens, Surface*
  • Base Sequence
  • Binding Sites
  • Cell Nucleus / metabolism
  • Cytoplasm / metabolism
  • DNA Primers
  • ELAV Proteins
  • ELAV-Like Protein 1
  • Humans
  • Mice
  • Mutagenesis, Site-Directed
  • Plasminogen Activator Inhibitor 2 / genetics*
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / metabolism*
  • Tumor Cells, Cultured

Substances

  • 3' Untranslated Regions
  • Antigens, Surface
  • DNA Primers
  • ELAV Proteins
  • ELAV-Like Protein 1
  • ELAVL1 protein, human
  • Plasminogen Activator Inhibitor 2
  • RNA, Messenger
  • RNA-Binding Proteins