title: An opioid growth factor receptor (OGFR) for [Met5]-enkephalin in Chlamys farreri.
abstract: Opioid growth factor receptor (OGFR) is a receptor for [Met(5)]-enkephalin and plays important roles in the regulation of cell growth and embryonic development. In the present study, a cDNA of 2381 bp for the scallop Chlamys farreri OGFR (designated as CfOGFR) was identified by rapid amplification of cDNA ends (RACE) approach and expression sequence tag (EST) analysis. The complete cDNA sequence of CfOGFR contained an open reading frame (ORF) of 1200 bp, which encoded a protein of 399 amino acids. The amino acid sequence of CfOGFR shared 33-64% similarity with other OGFRs. There was a low complexity domain and a conserved OGFR_N domain at the N-terminal of CfOGFR. The mRNA transcripts of CfOGFR were constitutively expressed in the tested tissues with the highest expression level in hepatopancreas. During the early embryonic development, the mRNA transcripts of CfOGFR could be detected in different development stages, where the expression level presented a downward trend as a whole. The stimulations of LPS, Glu and poly (I:C) significantly induced the expression of CfOGFR mRNA in hemocytes (P < 0.05), while PGN stimulation exerted no influence. Co-IP and western blot results revealed that the CfOGFR in hemocytes displayed high affinity and specificity to [Met(5)]-enkephalin. Exogenous [Met(5)]-enkephalin was observed to inhibit the proliferation of HEK293T cells transfected with pcDNA3.1(+)-CfOGFR in a time and dosage dependent manner. These results collectively indicated that CfOGFR, as a homolog of OGFRs in C. farreri, played an important role in cells proliferation, and might be involved in the immune response of scallops.
authors: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Rd., Qingdao 266071, China.
authors: Ying
authors: Y
authors: Guo
authors: Lingling
authors: L
authors: Wang
authors: Zhi
authors: Z
authors: Zhou
authors: Mengqiang
authors: M
authors: Wang
authors: Rui
authors: R
authors: Liu
authors: Leilei
authors: L
authors: Wang
authors: Qiufen
authors: Q
authors: Jiang
authors: Linsheng
authors: L
authors: Song
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D049109:Cell Proliferation; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006434:Hemocytes / Q000276:immunology / Q000378:metabolism; D007113:Immunity, Innate; D008969:Molecular Sequence Data; D009928:Organ Specificity; D049897:Pectinidae / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D010802:Phylogeny; D011070:Poly I-C / Q000008:administration & dosage; D016133:Polymerase Chain Reaction; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011957:Receptors, Opioid / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D016415:Sequence Alignment; D047071:beta-Glucans / Q000008:administration & dosage
chemical_list: D018076:DNA, Complementary; D011135:Polysaccharides, Bacterial; D012333:RNA, Messenger; D011957:Receptors, Opioid; D047071:beta-Glucans; C033593:methionine-enkephalin receptor; D011070:Poly I-C