title: Ubiquitins of Bombyx mori nucleopolyhedrovirus and Helicoverpa armigera nucleopolyhedrovirus show distinct subcellular localization in infected cells.
abstract: Ubiquitin (UB) is a conserved protein that regulates a number of processes in eukaryotic cells. Nearly all lepidopteran baculoviruses encode UB homologs showing a partial sequence identity with human UB (Hu-UB). In this study, the sequence, predicted 3D-structure and subcellular localization of UB homologs encoded by two different nucleopolyhedroviruses of Bombyx mori (BmNPV) and Helicoverpa armigera (HaNPV) were compared. UBs of BmNPV and HaNPV (Bm-UB, Ha-UB, respectively) shared only 73% of sequence identity of the different aa in relation to Hu-UB being localized in non-conserved parts, namely in two heterogeneous regions of aa 15-32 and aa 53-60. Interestingly, Bm-UB and Ha-UB share the same seven lysines except for an additional Lys54 in Bm-UB. However, in spite of the sequence heterogeneity, Bm-UB and Ha-UB have a similar predicted 3D-structure. A difference in their subcellular localization during virus growth in insect cell lines was found in the late stage of formation of occlusion-derived virus (ODV). In particular Bm-UB was localized mainly and evenly in the nucleus, while Ha-UB on the nuclear membrane. These data suggest that (i) UBs, besides being engaged in various cellular processes, have a role in specific processes of virus growth, and (ii) Bm-UB and Ha-UB may show certain different activities associated with the virus growth.
authors.affiliation: Institute for Life Science, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu, P.R. China.
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Guo
authors.forename: Y M
authors.initials: YM
authors.lastname: Zhu
authors.forename: G H
authors.initials: GH
authors.lastname: Li
authors.forename: K P
authors.initials: KP
authors.lastname: Chen
authors.forename: C X
authors.initials: CX
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx; D006801:Humans; D008969:Molecular Sequence Data; D009036:Moths; D017924:Nucleopolyhedroviruses / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D016415:Sequence Alignment; D014452:Ubiquitins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D014452:Ubiquitins; D014764:Viral Proteins