AU-rich elements in the 3′-UTR regulate the stability of the 141 amino acid isoform of parathyroid hormone-related protein mRNA

Abstract

We demonstrated previously that parathyroid hormone-related protein (PTHrP) 1-141 mRNA is the least stable of three isoforms and is the only isoform that is stabilized by TGF-β. In order to understand how PTHrP mRNA is stabilized by TGF-β, we first sought to elucidate the mechanism(s) that are responsible for the instability of PTHrP isoform 1-141 mRNA. The 3′-UTR of isoform 1-141 contains four AU-rich elements (AREs), which are known to mediate mRNA degradation. We utilized a luciferase reporter system to test whether these four AREs are responsible for the short half-life of PTHrP 1-141 mRNA. Our results demonstrated that ARE elements in the 3′-UTR of PTHrP 1-141 mRNA play a significant role in regulation of the stability of the mRNA. It is known that AREs mediate their effects on mRNA stability through a number of ARE-binding proteins that recruit the exosome, a complex of exonucleases that degrades the mRNA. We identified tristetraproline (TTP) as an RNA-binding protein that may be involved in ARE-mediated degradation of PTHrP 1-141 mRNA.

Non-coding functions of alternative pre-mRNA splicing in development

“…For instance, the choice between three A3Es in mRNA of human parathyroid hormone-related protein (PTHrP) involved in bone development gives rise to 139, 173 or 141 amino acid (aa)-long protein species [64] . Of the three mRNA isoforms, the one encoding the 141 aa-long protein is the least stable due to the presence of AREs in its 3′UTR.…”