Adenovirus proteins that regulate susceptibility to TNF also regulate the activity of PLA2

Expression of the adenovirus E1A protein induces susceptibility to TNF. To counteract this effect, the adenovirus encodes a number of gene products that preserve host cell resistance to TNF. The E1B-19K protein, the E3 14.7 K protein, and the E3 10.4/14.5 K dimer each function in different cell types to provide resistance to TNF. Expression of E1A also results in the activation of PLA₂ and the release of arachidonic acid from the dying cell. The E3 14.7 K protein can prevent the activation of PLA₂, suggesting that in addition to providing host cell resistance to TNF, this protein also functions in an anti-inflammatory manner.