Archives of Virology

, Volume 154, Issue 9, pp 1409–1416 | Cite as

Characterization of Singapore grouper iridovirus (SGIV) ORF086R, a putative homolog of ICP18 involved in cell growth control and virus replication

  • Liqun Xia
  • Jianhao Cao
  • Xiaohong Huang
  • Qiwei QinEmail author
Original Article


Singapore grouper iridovirus (SGIV), as a causative agent of serious systemic disease, causes significant economic losses in grouper aquaculture. In this study, a novel ICP18 homolog encoded by SGIV ORF086R was identified and characterized. Strikingly, ICP18 homologs can be found in all ranaviruses, but not in other sequenced large DNA viruses. SGIV ICP18 is an immediate-early gene and begins to be transcribed as early as 2 h post-infection (p.i.). Western blotting indicated that SGIV ICP18 is translated as early as 6 h p.i. and is a viral non-envelope protein. Subcellular localization analysis revealed that the SGIV ICP18 displays a finely punctate cytoplasmic pattern. Furthermore, overexpression of SGIV ICP18 can promote the growth of grouper embryonic cells (GP) and contribute to SGIV replication. These results should offer important insights into the pathogenesis of ranaviruses.


Cell Growth Control ICP18 Protein Punctate Fluorescence ICP18 Gene Ambystoma Tigrinum Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by grants from the National Basic Research Program of China (973) (2006CB101802), the National High Technology Development Program of China (863) (2006AA09Z445, 2006AA09Z411), National Natural Science Foundation of China (30700616, 30725027) and Chinese Academy of Sciences (KZCX2-YW-BR-08). We thank Professor Zaohe Wu and Jichang Jian, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, for providing facilities to perform the work of gene cloning, plasmid construction and antibody preparation.


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Liqun Xia
    • 1
  • Jianhao Cao
    • 1
  • Xiaohong Huang
    • 2
  • Qiwei Qin
    • 2
    Email author
  1. 1.State Key Laboratory of Biocontrol, School of Life ScienceSun Yat-sen UniversityGuangzhouChina
  2. 2.Laboratory of Marine Biology, South China Sea Institute of OceanologyThe Chinese Academy of SciencesGuangzhouChina

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