Differential splicing of transcripts encoding the orphanin FQ/nociceptin precursor.
Orphanin FQ or nociceptin (OFQ/N), the heptadecapeptide agonist for the NOP receptor, is derived by proteolytic processing from a precursor protein, preproOFQ/N. Previous studies have reported alternative splicing between exons 3 and 4 of the mouse OFQ/N transcript, which, upon translation, would yield precursor proteins with different C-termini. Using RT-PCR, we identified similar alternative splicing of preproOFQ/N transcripts in humans and rats. In addition, we identified two novel human preproOFQ/N splice variants from which exon 2 has been excised and which also undergo alternative splicing between exons 3 and 4. Exon 2 contains the translational start site for preproOFQ/N and encodes the signal peptide sequence. In vitro translation of cRNAs lacking exon 2 yields shorter translation products which arise from an alternative initiator methionine located within exon 3. The resulting proteins would lack a signal peptide sequence, which would likely alter their cellular trafficking and processing.
Arjomand
J
J
Neuroscience Interdepartmental Program, UCLA, Los Angeles, CA 90024-1759, USA.
Evans
C J
CJ
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002540:Cerebral Cortex / Q000737:chemistry; D005091:Exons; D015870:Gene Expression; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D018847:Opioid Peptides / Q000737:chemistry / Q000235:genetics*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013737:Testis / Q000737:chemistry; D014018:Tissue Distribution; D000097629:Nociceptin
D018847:Opioid Peptides; D012333:RNA, Messenger; D000097629:Nociceptin