Research
| Title： | Andrias davidianus ranavirus 1R encoding a delayed-early protein promotes cell proliferation by driving cell cycle progression into S phase |
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| First author： | Yu, N-T; Ke, F.; Zhang, Q-Y |
| Journal： | ACTA VIROLOGICA |
| Years： | 2020 |
| DOI： | 10.4149/av_2020_102 |
| Abstract： | Andrias davidianus ranavirus 1R (ADRV-1R), a core gene of the family Iridoviridae, is predicted to encode a viral transcription factor (vTF) since the protein contains a virus late transcription factor-3 like (VLTF3 like) domain. However, its characteristics and function are still unclear. In this study, the transcription and expression of ADRV-1R were investigated in Chinese giant salamander thymus cells (GSTCs). ADRV-1R transcription starts 6 hours post-infection (hpi), while the protein expression starts 8 hpi. Drug inhibition assay showed that the transcripts are inhibited by cycloheximide (CHX), a de novo protein synthesis inhibitor, indicating that ADRV-1R is a viral delayed-early (DE) gene. Subcellular localization showed that ADRV-1R is distributed in the cell nucleus and cytoplasm. The effect of ADRV-1R overexpression on cell proliferation and virus titer was analyzed. ADRV-1R overexpression significantly promoted the cell proliferation starting at day 2. Flow cytometry analysis further indicated that the protein promotes the GSTC cell cycle progression from GI phase into S phase (Gl/S transition). Moreover, ADRV-1R overexperession significantly increased ADRV titer in GSTCs. The virus titer was 6.3-6.9-fold higher at 36 hpi and further after than the control GSTC lines. These data showed that ADRV-1R is a delayed-early protein promoting cell proliferation and virus titers. |
