Phosphorylation of poly(rC) binding protein 1 (PCBP1) contributes to stabilization of mu opioid receptor (MOR) mRNA via interaction with AU-rich element RNA-binding protein 1 (AUF1) and poly A binding protein (PABP)

Cheol Kyu Hwang, Yadav Wagley, Ping Yee Law, Li Na Wei, Horace H. Loh

Research output: Contribution to journalArticle

4 Scopus citations


Gene regulation at the post-transcriptional level is frequently based on cis- and trans-acting factors on target mRNAs. We found a C-rich element (CRE) in mu-opioid receptor (MOR) 3′-untranslated region (UTR) to which poly (rC) binding protein 1 (PCBP1) binds, resulting in MOR mRNA stabilization. RNA immunoprecipitation and RNA EMSA revealed the formation of PCBP1-RNA complexes at the element. Knockdown of PCBP1 decreased MOR mRNA half-life and protein expression. Stimulation by forskolin increased cytoplasmic localization of PCBP1 and PCBP1/MOR 3′-UTR interactions via increased serine phosphorylation that was blocked by protein kinase A (PKA) or (phosphatidyl inositol-3) PI3-kinase inhibitors. The forskolin treatment also enhanced serine- and tyrosine-phosphorylation of AU-rich element binding protein (AUF1), concurrent with its increased binding to the CRE, and led to an increased interaction of poly A binding protein (PABP) with the CRE and poly(A) sites. AUF1 phosphorylation also led to an increased interaction with PCBP1. These findings suggest that a single co-regulator, PCBP1, plays a crucial role in stabilizing MOR mRNA, and is induced by PKA signaling by conforming to AUF1 and PABP.

Original languageEnglish (US)
Pages (from-to)113-130
Number of pages18
StatePublished - Jan 20 2017



  • 3′-Untranslated region
  • Mu opioid receptor
  • Protein kinase A signaling
  • RNA binding protein
  • RNA stability

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