Description
Background: PDCD4 (programmed cell death protein 4) was identified as a suppressor of neoplastic transformation (1). It interacts with eukaryotic initiation factors eIF4AI and eIF4AII (2). PDCD4 colocalizes with eIF4A in the cytoplasm and inhibits the activity of eIF4A as an ATP-dependent RNA helicase (2). PDCD4 inhibits cap-dependent translation (2). Upon stimulation by mitogens, PDCD4 is phosphorylated on Ser67 by S6K1 kinase and then degraded through the ubiquitin pathway leading to enhanced translation and cell growth (3)