title: Molecular cloning, characterization and expression analysis of (B-cell lymphoma-2 associated X protein) Bax in the orange-spotted grouper (Epinephelus coioides) after the Vibrio alginolyticus challenge.
abstract: Bax is a pro-apoptotic member of Bcl-2 like superfamily, playing an important role in regulating the apoptosis. In this study, the full-length Bax (EcBax) was obtained, containing a 5'UTR of 64 bp, an ORF of 579 bp and a 3'UTR of 1021 bp. The EcBax gene encoded a polypeptide of 192 amino acids with an estimated molecular mass of 21.55 KDa and a predicted isoelectric point (pI) of 6.75. The deduced amino acid sequence analysis showed that EcBax comprised the conserved residues and the characteristic domains known to the critical function of Bax. qRT-PCR analysis revealed that EcBax mRNA was broadly expressed in all of the examined tissues, while the highest expression level was observed in blood, followed by the expression in liver, gill, spleen, kidney, heart, muscle and intestine. A sharp increase of EcBax expression was observed in the vibrio challenge group by comparing with those in the control. Subcellular localization analysis revealed that EcBax was predominantly localized in the cytoplasm. EcBax exerted a regulatory role in modulating the mitochondrial membrane potential, promoting the cytochrome c release, and then activating the downstream caspase signaling. Moreover, the overexpression of EcBax can decrease the cell viability and antagonize NF-kB, AP-1, Stat3 promoter activity in Hela cells. These results indicate that EcBax containing the conserved domain of pro-apoptotic member of Bcl-2 family may disrupt the mammalian signaling and play a regulative role in the apoptotic process.
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Sheng-Wei
authors.initials: SW
authors.lastname: Luo
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China. Electronic address: wangwn@scnu.edu.cn.
authors.forename: Wei-Na
authors.initials: WN
authors.lastname: Wang
authors.affiliation: Division of Immunology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.
authors.forename: Zuo-Ming
authors.initials: ZM
authors.lastname: Sun
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Fu-Xing
authors.initials: FX
authors.lastname: Xie
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Jing-Rong
authors.initials: JR
authors.lastname: Kong
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Chang-Hong
authors.initials: CH
authors.lastname: Cheng
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D001483:Base Sequence; D002470:Cell Survival; D003001:Cloning, Molecular; D017124:Conserved Sequence; D005393:Fish Diseases / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D006367:HeLa Cells; D006801:Humans; D007113:Immunity, Innate; D008070:Lipopolysaccharides / Q000494:pharmacology; D008099:Liver / Q000276:immunology / Q000378:metabolism; D009928:Organ Specificity; D010473:Perciformes / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D010802:Phylogeny; D021381:Protein Transport; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D014735:Vibrio Infections / Q000276:immunology / Q000378:metabolism / Q000382:microbiology / Q000662:veterinary*; D044149:Vibrio alginolyticus / Q000276:immunology*; D051028:bcl-2-Associated X Protein / Q000235:genetics* / Q000378:metabolism
chemical_list: D029941:Fish Proteins; D008070:Lipopolysaccharides; D051028:bcl-2-Associated X Protein
keywords: Bax; Epinephelus coioides; Gene expression; Vibrio alginolyticus