E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity
<p>E2F-1 is the major cellular target of pRB and is regulated by pRB during cell proliferation. Interaction between pRB and E2F-1 is dependent on the phosphorylation status of pRB. Despite the fact that E2F-1 and pRB have antagonistic activities when they are overexpressed, the role of the E2F...
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| Format: | Article |
| Language: | English |
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Ivyspring International Publisher
2010-01-01
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| Series: | International Journal of Biological Sciences |
| Online Access: | http://www.biolsci.org/v06p0382.htm |
| _version_ | 1818339844441505792 |
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| author | Fikret Sahin, Todd L. Sladek |
| author_facet | Fikret Sahin, Todd L. Sladek |
| author_sort | Fikret Sahin, Todd L. Sladek |
| collection | DOAJ |
| description | <p>E2F-1 is the major cellular target of pRB and is regulated by pRB during cell proliferation. Interaction between pRB and E2F-1 is dependent on the phosphorylation status of pRB. Despite the fact that E2F-1 and pRB have antagonistic activities when they are overexpressed, the role of the E2F-1-pRB interaction in cell growth largely remains unknown. Ideally, it would be better to study the properties of a pRB mutant that fails to bind to E2F, but retains all other activities. To date, no pRB mutation has been characterized in sufficient detail to show that it specifically eliminates E2F binding but leaves other interactions intact. An alternative approach to this issue is to ask whether mutations that change E2F proteins binding affinity to pRB are sufficient to change cell growth in aspect of cell cycle and tumor formation. Therefore, we used the E2F-1 mutants including E2F-1/S332-7A, E2F-1/S375A, E2F-1/S403A, E2F-1/Y411A and E2F-1/L132Q that have different binding affinities for pRB to better understand the roles of the E2F-1 phosphorylation and E2F-1-pRB interaction in the cell cycle, as well as in transformation and gene expression. Data presented in this study suggests that <i>in vivo</i> phosphorylation at amino acids 332-337, 375 and 403 is important for the E2F-1 and pRB interaction <i>in vivo</i>. However, although E2F-1 mutants 332-7, 375 and 403 showed similar binding affinity to pRB, they showed different characteristics in transformation efficiency, G<sub>0</sub> accumulation, and target gene experiments.</p> |
| first_indexed | 2024-12-13T15:33:28Z |
| format | Article |
| id | doaj.art-265d4393f9ba4668a1c58b4fd0fdcf7a |
| institution | Directory Open Access Journal |
| issn | 1449-2288 |
| language | English |
| last_indexed | 2024-12-13T15:33:28Z |
| publishDate | 2010-01-01 |
| publisher | Ivyspring International Publisher |
| record_format | Article |
| series | International Journal of Biological Sciences |
| spelling | doaj.art-265d4393f9ba4668a1c58b4fd0fdcf7a2022-12-21T23:40:05ZengIvyspring International PublisherInternational Journal of Biological Sciences1449-22882010-01-0164382395E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activityFikret Sahin, Todd L. Sladek<p>E2F-1 is the major cellular target of pRB and is regulated by pRB during cell proliferation. Interaction between pRB and E2F-1 is dependent on the phosphorylation status of pRB. Despite the fact that E2F-1 and pRB have antagonistic activities when they are overexpressed, the role of the E2F-1-pRB interaction in cell growth largely remains unknown. Ideally, it would be better to study the properties of a pRB mutant that fails to bind to E2F, but retains all other activities. To date, no pRB mutation has been characterized in sufficient detail to show that it specifically eliminates E2F binding but leaves other interactions intact. An alternative approach to this issue is to ask whether mutations that change E2F proteins binding affinity to pRB are sufficient to change cell growth in aspect of cell cycle and tumor formation. Therefore, we used the E2F-1 mutants including E2F-1/S332-7A, E2F-1/S375A, E2F-1/S403A, E2F-1/Y411A and E2F-1/L132Q that have different binding affinities for pRB to better understand the roles of the E2F-1 phosphorylation and E2F-1-pRB interaction in the cell cycle, as well as in transformation and gene expression. Data presented in this study suggests that <i>in vivo</i> phosphorylation at amino acids 332-337, 375 and 403 is important for the E2F-1 and pRB interaction <i>in vivo</i>. However, although E2F-1 mutants 332-7, 375 and 403 showed similar binding affinity to pRB, they showed different characteristics in transformation efficiency, G<sub>0</sub> accumulation, and target gene experiments.</p>http://www.biolsci.org/v06p0382.htm |
| spellingShingle | Fikret Sahin, Todd L. Sladek E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity International Journal of Biological Sciences |
| title | E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity |
| title_full | E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity |
| title_fullStr | E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity |
| title_full_unstemmed | E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity |
| title_short | E2F-1 binding affinity for pRb is not the only determinant of the E2F-1 activity |
| title_sort | e2f 1 binding affinity for prb is not the only determinant of the e2f 1 activity |
| url | http://www.biolsci.org/v06p0382.htm |
| work_keys_str_mv | AT fikretsahintoddlsladek e2f1bindingaffinityforprbisnottheonlydeterminantofthee2f1activity |