E1 protein
70-kDa ATP-dependent helicase that binds specifically
to the origin to initiate replication of the virus.
Essential for viral DNA replication initiation
stage and the
regulation of early transcription.
E2 protein
A polypeptide of 350-500 amino acids in length.
Often referred to as E2-TA or E2 transactivator.
Transcription factor essential for
viral DNA replication. Binds E1 to
facilitate the replication initiation of
the viral DNA and ultimately the viral genome's
encapsidation.
E4 protein
Interacts with cytoskeletal proteins,
facilitates viral assembly. Expressed at
productive infection stage.
Oncogenes
E5 protein
Some transforming activity,
up-regulate growth factor receptors.
E6 protein
Oncogene. Directs p53 (tumor suppressor protein)
ubiquitin-mediated degradation. Together with E7
involved in malignant transformation and
eventual immortalization
of keratinocytes.
E7 proteinMeSH
ONCOGENE PROTEINS from papillomavirus that deregulate the CELL CYCLE
of infected cells and lead to NEOPLASTIC CELL TRANSFORMATION.
Papillomavirus E7 proteins have been shown to interact with
various regulators of the cell cycle including RETINOBLASTOMA
PROTEIN and certain cyclin-dependent kinase inhibitors.
Year introduced: 2006.
