RESUMO
The scavenger receptor, Croquemort is a member of the CD36 superfamily comprising transmembrane proteins involved in the recognition of polyanionic ligands. Various researchers have proved that members of the CD36 superfamily are involved in immunity and developmental processes. In the present study, we report a cDNA encoding the kuruma shrimp, Marsupenaeus japonicus Croquemort scavenger receptor (MjSCRBQ) obtained from a cDNA library of lymphoid organ by RACE amplification. The full-length cDNA of 2098 bp consists an open reading frame of 1596 nucleotides that translates into a 532-amino acid putative protein, with a 5' untranslated region of 323 bp and 3' UTR of 153 bp. The MjSCRBQ is constitutively expressed in gills, heart, hemolymph, hepatopancreas, intestine, lymphoid organ, muscle, nerve, and stomach and at high levels in the brain. Expression analysis in lymphoid organs of shrimp infected with white spot syndrome virus (WSSV) revealed high levels of MjSCRBQ 72 and 120 h post-infection. The MjSCRBQ contains putative functional domains including transmembrane domains and a CD36 domain. Multiple alignments of MjSCRBQ amino acid sequences showed significant identity with Drosophila melanogaster SCRBQ (31%), Salmo salar SCRBQ (29%), Homo sapiens SCRBQ (28%) and Rattus norvegicus SCRBQ (30%). In a phylogenetic analysis, MjSCRBQ was identified in the invertebrate scavenger receptor cluster. This is the first report in crustaceans of the identification and characterization of a Croquemort scavenging receptor.
Assuntos
Perfilação da Expressão Gênica , Penaeidae/genética , Receptores Depuradores Classe B/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Brânquias/metabolismo , Hemolinfa/metabolismo , Hepatopâncreas/metabolismo , Interações Hospedeiro-Patógeno , Tecido Linfoide/metabolismo , Tecido Linfoide/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptores Depuradores Classe B/classificação , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Vírus da Síndrome da Mancha Branca 1/fisiologiaRESUMO
Nitric oxide (NO) signaling is involved in many physiological processes in vertebrates and invertebrates. In crustaceans, nitric oxide synthase (NOS) plays a significant role in the regulation of the nervous system and in innate immunity. Here, we describe the entire cDNA sequence (4616 bp) of the kuruma shrimp Marsupenaeus japonicus NOS (Mj NOS) generated using the reverse transcriptase-polymerase chain reaction (RT-PCR) and 5'- and 3'- rapid amplification PCRs of cDNA ends from brain and gill mRNAs. The open reading frame of Mj NOS encoded a protein of 1187 amino acids with an estimated mass of 134 kDa, and had an 82.3% sequence homology with the NOS gene of the land crab Gecarcinus lateralis. Highly conserved amino acid sequences in heme and tetrahydrobiopterin were observed in the oxygenase domain. FMN, FAD and NADPH were found in the reductase domain. Mj NOS mRNA was constitutively expressed in the brain, gill, intestine, thoracic ganglion and testis of the kuruma shrimp. When Vibrio penaeicida was injected into the kuruma shrimp, Mj NOS was expressed in the brain, gill, heart, lymphoid organ, intestine and thoracic ganglion. Mj NOS expression in the gill reached its peak 12 h and decreased to its normal level 24 h after V. penaeicida injection.
Assuntos
Regulação Enzimológica da Expressão Gênica , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/imunologia , Penaeidae/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Perfilação da Expressão Gênica , Imunidade Inata , Modelos Moleculares , Dados de Sequência Molecular , Óxido Nítrico Sintase/química , Penaeidae/classificação , Penaeidae/imunologia , Penaeidae/metabolismo , Penaeidae/microbiologia , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Vibrio/fisiologiaRESUMO
A tumor necrosis factor (TNF) gene has been isolated and characterized in kuruma shrimp, Marsupenaeus japonicus, providing the first conclusive evidence for the existence of the TNF ligand in shrimp. The kuruma shrimp TNF (MjTNF) cDNA was composed of 1868 bp with a 262 bp 5'-untranslated region (UTR) and a 220 bp 3'-UTR, which was translated into a protein of 462 amino acid residues that included a predicted transmembrane domain of 23 amino acid residues (Trp20-Val42) and the TNF family signature (Pro321-Leu448). Homology analysis of MjTNF showed 30.7% and 26.7% identities with fruit fly (Drosophila melanogaster) Eiger and human (Homo sapiens) ectodysplasin A, respectively. The MjTNF gene was constitutively expressed in unstimulated organs of shrimp such as the muscle, stomach, brain and gill. In lymphoid organ cells, an enhanced expression of the MjTNF gene was observed following stimulation with peptidoglycan and polycytidylic acid. A high expression level of MjTNF was observed in vivo 2 h and 4 h after stimulation with lipopolysaccharide and Vibrio penaeicida, respectively. These observations suggest that MjTNF plays a role in the innate immune defense in kuruma shrimp. The discovery of shrimp TNF will allow a more complete and concrete understanding of shrimp inflammatory responses.