Mouse anti-E1A monoclonal antibody for IP, WB, ICC. The early region (E1) of the adenovirus genome, responsible for transforming activity, is localized within the left most 11% of the viral genome and consists of two transcriptional units E1A and E1B. E1A is sufficient for partial transformation and immortalization of primary cells. E1A gene products are necessary for normal levels of transcription of the other early regions of the adenovirus genome during productive infection and are able to either activate or repress the transcription of specific cellular genes. E1A forms specific complexes with cellular proteins including p105 causing inhibition of the cell cycle inducing arresting function of p105.