Identification of cellular proteins binding to the 3’UTR of Programmed Cell Death 4 mRNA

The aim of the project is to identify RNA-binding proteins (RBPs) that interact with the 3’ untranslated region (3’UTR) of the programmed cell death 4 (PDCD4) mRNA. PDCD4 is an inflammatory tumor suppressor gene. The translation of PDCD4 mRNA is regulated by multiple RBPs. The aim is to identify RBPs which are critical for regulating PDCD4 mRNA translation by binding to its 3’UTR. For this purpose, a biotinylated PDCD4 3’UTR RNA was incubated with cytoplasmic lysate from MCF7 human breast carcinoma cells and the RNA-protein complexes pulled down by streptavidin affinity chromatography. The proteins were then eluted and resolved by SDS-PAGE. One particular protein band, migrating close to 55 KDa marker was cut out and submitted for proteomic analysis by in gel digestion and mass spectrometry.