title: Characterization of white spot syndrome virus envelope protein VP51A and its interaction with viral tegument protein VP26.
abstract: In this study, we characterize a novel white spot syndrome virus (WSSV) structural protein, VP51A (WSSV-TW open reading frame 294), identified from a previous mass spectrometry study. Temporal-transcription analysis showed that vp51A is expressed in the late stage of WSSV infection. Gene structure analysis showed that the transcription initiation site of vp51A was 135 bp upstream of the translation start codon. The poly(A) addition signal overlapped with the translation stop codon, TAA, and the poly(A) tail was 23 bp downstream of the TAA. Western blot analysis of viral protein fractions and immunoelectron microscopy both suggested that VP51A is a viral envelope protein. Western blotting of the total proteins extracted from WSSV virions detected a band that was close to the predicted 51-kDa mass, but the strongest signal was around 72 kDa. We concluded that this 72-kDa band was in fact the full-length VP51A protein. Membrane topology assays demonstrated that the VP51A 72-kDa protein is a type II transmembrane protein with a highly hydrophobic transmembrane domain on its N terminus and a C terminus that is exposed on the surface of the virion. Coimmunoprecipitation, colocalization, and yeast two-hybrid assays revealed that VP51A associated directly with VP26 and indirectly with VP28, with VP26 acting as a linker protein in the formation of a VP51A-VP26-VP28 complex.
authors.affiliation: Department of Molecular Biotechnology, Da-Yeh University, Changhua, Taiwan. yschang@mail.dyu.edu.tw
authors.forename: Yun-Shiang
authors.initials: YS
authors.lastname: Chang
authors.forename: Wang-Jing
authors.initials: WJ
authors.lastname: Liu
authors.forename: Tsung-Lu
authors.initials: TL
authors.lastname: Chou
authors.forename: Yuan-Ting
authors.initials: YT
authors.lastname: Lee
authors.forename: Tai-Lin
authors.initials: TL
authors.lastname: Lee
authors.forename: Wei-Tung
authors.initials: WT
authors.lastname: Huang
authors.forename: Guang-Hsiung
authors.initials: GH
authors.lastname: Kou
authors.forename: Chu-Fang
authors.initials: CF
authors.lastname: Lo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism*; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D008970:Molecular Weight; D033561:Penaeidae; D011485:Protein Binding; D014158:Transcription, Genetic / Q000235:genetics; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D014771:Virion / Q000378:metabolism; D046848:White spot syndrome virus 1 / Q000235:genetics / Q000378:metabolism*
chemical_list: D036022:Capsid Proteins; D014759:Viral Envelope Proteins