Article

Cloning, expression and subcellular distribution of a Rana grylio virus late gene encoding ERV1 homologue.

State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan, China.
Molecular Biology Reports (impact factor: 2.93). 10/2008; 36(7):1651-9. DOI:10.1007/s11033-008-9365-6 pp.1651-9
Source: PubMed

ABSTRACT An essential for respiration and viability (ERV1) homologue, 88R, was cloned and characterized from Rana grylio virus (RGV). Database searches found its homologues in all sequenced iridoviruses, and sequence alignment revealed a highly conserved motif shared by all ERV1 family proteins: Cys-X-X-Cys. RT-PCR and western blot analysis revealed that 88R begins to transcribe and translate at 6 h postinfection (p.i.) and remains detectable at 48 h p.i. during RGV infection course. Furthermore, using drug inhibition analysis by a de novo protein synthesis inhibitor and a viral DNA replication inhibitor, RGV 88R was classified as a late (L) viral gene during the in vitro infection. 88R-EGFP fusion protein was observed in both the cytoplasm and nucleus of pEGFP-N3-88R transfected EPC cells. Although result of immunofluorescence is similar, 88R protein was not detected in viromatrix. Moreover, function of RGV 88R on virus replication were evaluated by RNAi assay. Nevertheless, effect of knockdown of RGV 88R expression on virus replication was not detected in cultured fish cell lines. Collectively, current data indicate that RGV 88R was a late gene of iridovirus encoding protein that distributed both the cytoplasm and nucleus.

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Keywords

6 h postinfection
 
88R-EGFP fusion protein
 
cultured fish cell lines
 
current data
 
Database searches
 
de novo protein synthesis inhibitor
 
ERV1 family proteins
 
essential
 
iridovirus encoding protein
 
pEGFP-N3-88R transfected EPC cells
 
Rana grylio virus
 
RGV
 
RGV 88R expression
 
RGV infection course
 
RNAi assay
 
sequence alignment
 
sequenced iridoviruses
 
viral DNA replication inhibitor
 
virus replication
 
western blot analysis
 

Fei Ke