Project description:This project aims to identify novel RNA binding proteins in the nematode, Caenorhabditis elegans. Since interactions between RNAs and proteins may be transient, these animals were crosslinked with UV light at 254 nm which promotes the covalent link between proteins and RNAs. After this, polyadenylated mRNAs were purified via oligo(dT) coupled to magentic beads under stringent conditions. Finally, samples were subjected to mass spectrometry analysis. To rule out the possibility of RNA-independent binding we also analysed other samples: i) samples digested with RNase one; ii) samples where we performed competition assays with polyadenylic acid
Project description:The Argonautes (AGOs) are widely expressed, evolutionarily conserved RNA binding proteins that play an important role in gene expression regulation. The AGOs bind to small regulatory noncoding RNAs such as micro RNAs (miRNAs), short interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs) etc. The small regulatory noncoding RNAs serve the function of guiding the AGOs to the right target RNAs by complementary base pairing. Additionally, the AGOs interact with GW182 (TNRC6A/-B/-C) proteins and together with small RNAs, they form an effector ribonucleo protein complex named, RNA Induced Silencing Complex (RISC) that regulates several aspects of transcriptional and post-transcriptional gene expression. ALG-1 (Argonaute Like Gene) and ALG-2 are the AGO proteins in C. elegans that are required for miRNA mediated gene expression regulation. Our efforts towards the characterization of the protein complexes comprised of ALG-1 led to the identification of DPF-3, a conserved protease belonging to clinically relevant Di Peptidyl Peptidase IV family, as the novel interacting partner of ALG-1. We have further explored the role of DPF-3 in AGO regulation.