Programmed cell death protein 4

Programmed cell death protein 4 (PDCD4) is a translation inhibitor that suppresses cap-dependent translation initiation by interfering with the eIF4A1–eIF4G interaction and blocking eIF4A helicase activity (UniProt: Q53EL6). Beyond its role in translation regulation, PDCD4 modulates c-Jun kinase activation, downregulates MAP4K1 expression to inhibit invasion-related signaling, and functions as a tumor suppressor by preventing transformation.

PDCD4 is widely expressed across tissues and participates in apoptotic pathways. The UniProt record lists no primary disease associations for this protein.

In Alzheimer's Disease, PDCD4 is upregulated in post-mortem AD brain tissue relative to age-matched controls (Chaparral AD proteomics), with a mean log2 fold-change of 0.679 across one subcellular fraction in TMT-labeled proteomics analysis. This elevation may reflect altered translational control and stress responses in AD pathology, though the functional significance of PDCD4 upregulation in neurodegeneration remains to be established.