Post-Transcriptional Regulation of the Human Mu-Opioid Receptor (MOR) by Morphine-Induced RNA Binding Proteins hnRNP K and PCBP1.
Expression of the mu-opioid receptor (MOR) protein is controlled by extensive transcriptional and post-transcriptional processing. MOR gene expression has previously been shown to be altered by a post-transcriptional mechanism involving the MOR mRNA untranslated region (UTR). Here, we demonstrate for the first time the role of heterogeneous nuclear ribonucleic acids (hnRNA)-binding protein (hnRNP) K and poly(C)-binding protein 1 (PCBP1) as post-transcriptional inducers in MOR gene regulation. In the absence of morphine, a significant level of MOR mRNA is sustained in its resting state and partitions in the translationally inactive polysomal fraction. Morphine stimulation activates the downstream targets hnRNP K and PCPB1 and induces partitioning of the MOR mRNA to the translationally active fraction. Using reporter and ligand binding assays, as well as RNA EMSA, we reveal potential RNP binding sites located in the 5'-untranslated region of human MOR mRNA. In addition, we also found that morphine-induced RNPs could regulate MOR expression. Our results establish the role of hnRNP K and PCPB1 in the translational control of morphine-induced MOR expression in human neuroblastoma (NMB) cells as well as cells stably expressing MOR (NMB1). J. Cell. Physiol. 232: 576-584, 2017. © 2016 Wiley Periodicals, Inc.
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota.
Kyu Young
KY
Song
Subtropical Horticulture Research Institute, College of Applied Life Science, Jeju National University, Jeju, Jeju, Republic of Korea.
Hack Sun
HS
Choi
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota.
Ping-Yee
PY
Law
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota.
Li-Na
LN
Wei
Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota.
Horace H
HH
Loh
D020121:5' Untranslated Regions / Q000235:genetics; D000818:Animals; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation / Q000187:drug effects*; D034641:Heterogeneous-Nuclear Ribonucleoprotein K / Q000235:genetics* / Q000378:metabolism; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D011132:Polyribosomes / Q000187:drug effects / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins; D017450:Receptors, Opioid, mu / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects*; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
D020121:5' Untranslated Regions; D004268:DNA-Binding Proteins; D034641:Heterogeneous-Nuclear Ribonucleoprotein K; D034441:Heterogeneous-Nuclear Ribonucleoproteins; C485764:OPRM1 protein, human; C094604:PCBP1 protein, human; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D017450:Receptors, Opioid, mu; D009020:Morphine