Programmed Cell Death Protein 4 (PDCD4)

PDCD4 encodes a protein localized to the nucleus in proliferating cells. Expression of this gene is modulated by cytokines in natural killer and T cells. The gene product is thought to play a role in apoptosis but the specific role has not yet been determined. Two transcripts encoding different isoforms have been identified.The deduced 458-amino acid protein has a calculated molecular mass of 50.6 kD. PDCD4 is an acidic protein with characteristics of a nuclear nonhistone protein. It contains 2 overlapping GxGxxG nucleotide-binding motifs, which are characteristic of protein kinases, but it does not have a kinase catalytic domain. PDCD4 also has several putative serine and threonine phosphorylation sites. Northern blot analysis detected transcripts of about 2.7 and 3.8 kb in HeLa cell total RNA.