Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways.
Grouper iridovirus (GIV) belongs to the genus Ranavirus of the family Iridoviridae; the genomes of such viruses contain an anti-apoptotic caspase recruitment domain (CARD) gene. The GIV-CARD gene encodes a protein of 91 amino acids with a molecular mass of 10,505 Daltons, and shows high similarity t...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2015-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4457926?pdf=render |
| _version_ | 1830515596716933120 |
|---|---|
| author | Chien-Wen Chen Ming-Shan Wu Yi-Jen Huang Pei-Wen Lin Chueh-Ju Shih Fu-Pang Lin Chi-Yao Chang |
| author_facet | Chien-Wen Chen Ming-Shan Wu Yi-Jen Huang Pei-Wen Lin Chueh-Ju Shih Fu-Pang Lin Chi-Yao Chang |
| author_sort | Chien-Wen Chen |
| collection | DOAJ |
| description | Grouper iridovirus (GIV) belongs to the genus Ranavirus of the family Iridoviridae; the genomes of such viruses contain an anti-apoptotic caspase recruitment domain (CARD) gene. The GIV-CARD gene encodes a protein of 91 amino acids with a molecular mass of 10,505 Daltons, and shows high similarity to other viral CARD genes and human ICEBERG. In this study, we used Northern blot to demonstrate that GIV-CARD transcription begins at 4 h post-infection; furthermore, we report that its transcription is completely inhibited by cycloheximide but not by aphidicolin, indicating that GIV-CARD is an early gene. GIV-CARD-EGFP and GIV-CARD-FLAG recombinant proteins were observed to translocate from the cytoplasm into the nucleus, but no obvious nuclear localization sequence was observed within GIV-CARD. RNA interference-mediated knockdown of GIV-CARD in GK cells infected with GIV inhibited expression of GIV-CARD and five other viral genes during the early stages of infection, and also reduced GIV infection ability. Immunostaining was performed to show that apoptosis was effectively inhibited in cells expressing GIV-CARD. HeLa cells irradiated with UV or treated with anti-Fas antibody will undergo apoptosis through the intrinsic and extrinsic pathways, respectively. However, over-expression of recombinant GIV-CARD protein in HeLa cells inhibited apoptosis induced by mitochondrial and death receptor signaling. Finally, we report that expression of GIV-CARD in HeLa cells significantly reduced the activities of caspase-8 and -9 following apoptosis triggered by anti-Fas antibody. Taken together, these results demonstrate that GIV-CARD inhibits apoptosis through both intrinsic and extrinsic pathways. |
| first_indexed | 2024-12-22T03:25:33Z |
| format | Article |
| id | doaj.art-84c199ea9af74851b4c218efff798fb6 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-22T03:25:33Z |
| publishDate | 2015-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-84c199ea9af74851b4c218efff798fb62022-12-21T18:40:36ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01106e012907110.1371/journal.pone.0129071Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways.Chien-Wen ChenMing-Shan WuYi-Jen HuangPei-Wen LinChueh-Ju ShihFu-Pang LinChi-Yao ChangGrouper iridovirus (GIV) belongs to the genus Ranavirus of the family Iridoviridae; the genomes of such viruses contain an anti-apoptotic caspase recruitment domain (CARD) gene. The GIV-CARD gene encodes a protein of 91 amino acids with a molecular mass of 10,505 Daltons, and shows high similarity to other viral CARD genes and human ICEBERG. In this study, we used Northern blot to demonstrate that GIV-CARD transcription begins at 4 h post-infection; furthermore, we report that its transcription is completely inhibited by cycloheximide but not by aphidicolin, indicating that GIV-CARD is an early gene. GIV-CARD-EGFP and GIV-CARD-FLAG recombinant proteins were observed to translocate from the cytoplasm into the nucleus, but no obvious nuclear localization sequence was observed within GIV-CARD. RNA interference-mediated knockdown of GIV-CARD in GK cells infected with GIV inhibited expression of GIV-CARD and five other viral genes during the early stages of infection, and also reduced GIV infection ability. Immunostaining was performed to show that apoptosis was effectively inhibited in cells expressing GIV-CARD. HeLa cells irradiated with UV or treated with anti-Fas antibody will undergo apoptosis through the intrinsic and extrinsic pathways, respectively. However, over-expression of recombinant GIV-CARD protein in HeLa cells inhibited apoptosis induced by mitochondrial and death receptor signaling. Finally, we report that expression of GIV-CARD in HeLa cells significantly reduced the activities of caspase-8 and -9 following apoptosis triggered by anti-Fas antibody. Taken together, these results demonstrate that GIV-CARD inhibits apoptosis through both intrinsic and extrinsic pathways.http://europepmc.org/articles/PMC4457926?pdf=render |
| spellingShingle | Chien-Wen Chen Ming-Shan Wu Yi-Jen Huang Pei-Wen Lin Chueh-Ju Shih Fu-Pang Lin Chi-Yao Chang Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. PLoS ONE |
| title | Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. |
| title_full | Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. |
| title_fullStr | Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. |
| title_full_unstemmed | Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. |
| title_short | Iridovirus CARD Protein Inhibits Apoptosis through Intrinsic and Extrinsic Pathways. |
| title_sort | iridovirus card protein inhibits apoptosis through intrinsic and extrinsic pathways |
| url | http://europepmc.org/articles/PMC4457926?pdf=render |
| work_keys_str_mv | AT chienwenchen iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT mingshanwu iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT yijenhuang iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT peiwenlin iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT chuehjushih iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT fupanglin iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways AT chiyaochang iridoviruscardproteininhibitsapoptosisthroughintrinsicandextrinsicpathways |