title: Characterization of Oyster Voltage-Dependent Anion Channel 2 (VDAC2) Suggests Its Involvement in Apoptosis and Host Defense.
abstract: Genomic and transcriptomic studies have revealed a sophisticated and powerful apoptosis regulation network in oyster, highlighting its adaptation to sessile life in a highly stressful intertidal environment. However, the functional molecular basis of apoptosis remains largely unexplored in oysters. In this study, we focused on a representative apoptotic gene encoding voltage-dependent anion channel 2 (VDAC2), a porin that abounds at the mitochondrial outer membrane. This is the first report on the identification and characterization of a VDAC gene in the Pacific oyster, Crassostrea gigas (CgVDAC2). The full length of CgVDAC2 was 1,738 bp with an open reading frame of 843 bp that encoded a protein of 281 amino acids. A four-element eukaryotic porin signature motif, a conserved ATP binding motif, and a VKAKV-like sequence were identified in the predicted CgVDAC2. Expression pattern analysis in different tissues and developmental stages as well as upon infection by ostreid herpesvirus 1 revealed the energy supply-related and immunity-related expression of CgVDAC2. CgVDAC2 was co-localized with mitochondria when it was transiently transfected into HeLa cells. Overexpression of CgVDAC2 in HEK293T cells suppressed the UV irradiation-induced apoptosis by inhibiting the pro-apoptotic function of CgBak. RNA interference induced reduction in CgVDAC2 expression showed a promoted apoptosis level upon UV light irradiation in hemocytes. The yeast two-hybrid system and co-immunoprecipitation assay indicated a direct interaction between CgVDAC2 and the pro-apoptotic protein CgBak. This study revealed the function of VDAC2 in oyster and provided new insights into its involvement in apoptosis modulation and host defense in mollusks.
authors.affiliation: University of Chinese Academy of Sciences, Beijing, China.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.|National & Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Yingxiang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.|National & Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.|National & Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Qu
authors.affiliation: Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.|National & Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.|Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.|National & Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Guofan
authors.initials: G
authors.lastname: Zhang
mesh_terms: D000222:Adaptation, Physiological; D056704:Adaptive Immunity; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000528:radiation effects; D001483:Base Sequence; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D006367:HeLa Cells; D006434:Hemocytes / Q000528:radiation effects; D006564:Herpesviridae; D006801:Humans; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D009928:Organ Specificity; D010125:Ostreidae / Q000235:genetics / Q000276:immunology / Q000378:metabolism* / Q000821:virology; D025941:Protein Interaction Mapping; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014466:Ultraviolet Rays; D050996:Voltage-Dependent Anion Channel 2 / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000378:metabolism
chemical_list: D024101:Mitochondrial Proteins; D011993:Recombinant Fusion Proteins; D050996:Voltage-Dependent Anion Channel 2; D050998:bcl-2 Homologous Antagonist-Killer Protein