Diffusion-ordered spectroscopy and saturation transfer difference NMR spectroscopy studies of selective interactions between ELAV protein fragments and an mRNA target

The crucial role of post-transcriptional processes in the control of gene expression opened a new route to translate basic mechanisms into clinical medicine. In this contest, ELAV proteins represent a family of well-characterized proteins that bind mRNA. Interestingly, preliminary data bode well that the ELAV-mediated mRNA stabilization is a mechanism relevant to Alzheimer Disease. Herein we analyzed four peptides, belonging to RNA Recognition Motif of ELAVs, in presence of a mRNA fragment from Tumor Necrosis Factor α, by NMR techniques with the final aim to get insight into the interaction mechanism. Saturation Transfer Difference and Diffusion Order NMR experiments showed that appropriate mixtures of peptides (and not each peptide individually) bind effectively to the biological target. DOSY technique was applied here for the first time to study mRNA:peptides complexes. For each peptide the 3D structure was also determined by NOE analysis supported by molecular dynamics simulations