Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University , Chengdu, People's Republic of China .
DNA Cell Biol. 2014 Apr;33(4):259-70. doi: 10.1089/dna.2013.2235. Epub 2014 Feb 12.
We here report the cloning, tissue expression, and functional analyses of the two pig vasoactive intestinal polypeptide (VIP) receptors (pVPAC1-R and pVPAC2-R). The cloned full-length pVPAC1-R and pVPAC2-R share high structural similarity with their mammalian counterparts. Functional assay revealed that the full-length pVPAC1-R and pVPAC2-R-expressed Chinese hamster ovary (CHO) cells could be activated by pVIP and pPACAP38 potently, indicating that pVPAC1-R and pVPAC2-R are capable of binding VIP and pituitary adenylate cyclase-activating polypeptide (PACAP). In addition to the identification of the transcripts encoding the two full-length receptors, multiple splice transcript variants were isolated. Comparison with the pig genome database revealed that pVPAC1-R and pVPAC2-R share a unique gene structure with 14 exons different from other vertebrates. Reverse transcription and polymerase chain reaction (RT-PCR) assays further showed that the transcript encoding the full-length pVPAC2-R is widely expressed in all adult tissues whereas the splice variants of pVPAC1-R are predominantly expressed in all tissues instead of the transcript encoding the full-length receptor, hinting that pVPAC2-R may play more important roles than pVPAC1-R in mediating VIP and PACAP actions. Our present findings help to elucidate the important role of VIP and PACAP and promote to rethink of their species-specific physiological roles including their actions in regulation of phenotypic traits in pigs.
我们在此报告克隆、组织表达及功能分析两种猪血管活性肠肽（VIP）受体（pVPAC1-R 和 pVPAC2-R）。克隆全长的 pVPAC1-R 和 pVPAC2-R 与它们的哺乳动物对应物具有高度的结构相似性。功能分析显示，全长 pVPAC1-R 和 pVPAC2-R 表达的中国仓鼠卵巢（CHO）细胞可被 pVIP 和 pPACAP38 强烈激活，表明 pVPAC1-R 和 pVPAC2-R 能够结合 VIP 和垂体腺苷酸环化酶激活肽（PACAP）。除了鉴定出编码两种全长受体的转录本外，还分离出了多个剪接转录变体。与猪基因组数据库的比较表明，pVPAC1-R 和 pVPAC2-R 具有独特的基因结构，有 14 个外显子与其他脊椎动物不同。逆转录和聚合酶链反应（RT-PCR）检测进一步表明，全长 pVPAC2-R 的转录本广泛表达于所有成年组织，而 pVPAC1-R 的剪接变体主要表达于所有组织而不是全长受体的转录本，这表明 pVPAC2-R 可能在介导 VIP 和 PACAP 作用方面比 pVPAC1-R 发挥更重要的作用。我们目前的发现有助于阐明 VIP 和 PACAP 的重要作用，并促使重新思考它们在调节猪的表型特征方面的种特异性生理作用，包括它们的作用。
