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).
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.
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
Cheol Kyu
CK
Hwang
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA. Electronic address: ywagley@umn.edu.
Yadav
Y
Wagley
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
Ping-Yee
PY
Law
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
Li-Na
LN
Wei
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
Horace H
HH
Loh
D020413:3' Untranslated Regions; D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D005576:Colforsin / Q000494:pharmacology; D004268:DNA-Binding Proteins; D055785:Gene Knockdown Techniques; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D / Q000378:metabolism*; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D010766:Phosphorylation; D039102:Poly(A)-Binding Proteins / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D020871:RNA Stability; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D016601:RNA-Binding Proteins; D017450:Receptors, Opioid, mu / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
D020413:3' Untranslated Regions; D004268:DNA-Binding Proteins; C000630986:HNRNPD protein, human; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D034441:Heterogeneous-Nuclear Ribonucleoproteins; C485764:OPRM1 protein, human; C094604:PCBP1 protein, human; D039102:Poly(A)-Binding Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D017450:Receptors, Opioid, mu; D005576:Colforsin
3′-Untranslated region; Mu opioid receptor; Protein kinase A signaling; RNA binding protein; RNA stability