Adenovirus early region 1A

Adenovirus early region 1A (E1a or E1A) is a gene expressed during adenovirus replication to produce a variety of (E1A) proteins. Adenovirus early region 1A (E1a or E1A) is a gene expressed during adenovirus replication to produce a variety of (E1A) proteins. It has been considered an oncogene. It can behave as a tumour suppressor gene. Adenovirus early region 1A (E1A) encodes two major proteins in Ad5 that are able to cause many different effects in mammalian cells. After viral infection, they stimulate expression of other viral genes and can either enhance or repress expression of cellular genes. The addition of E1A DNA into cells may cause adverse biological effects, such as increasing p53 expression, causing DNA synthesis and cell cycle progression in quiescent cells, and inhibiting differentiation.