Kusum K. Singh

Starting from the birth of RNA molecules, many RNA-binding proteins (RBPs) associate with RNA to regulate its cytoplasmic fate. This assembly of RBPs on non-coding RNAs (ncRNAs) or mRNAs is called ribonucleoprotein particles (RNPs). The dynamic interaction between RBPs and RNA molecules decides mRNA biogenesis, pre-mRNA processing, export, localization, translation, and degradation—the deposition of RBPs on mRNAs couples transcription with post-transcriptional gene expression events. However, we do not have a comprehensive idea about the sequential assembly, composition, and roles of many RBPs. Thus, our goal is to understand the assembly and functions of various mRNP interactomes to decipher the molecular events at different stages of gene expression.
During the splicing of premature mRNA, the spliceosome deposits a multiprotein complex termed Exon-Juction Complex (EJC) onto the mRNAs. The core EJC subunits are eukaryotic translation initiation factor 4A3 (eIF4A3), Y14-MAGOH, and barentz (BTZ, CAS3, or MLN51). Many proteins transiently interact with the core EJC, and our focus of the study is the "Apoptosis and Splicing-Associated Protein (ASAP)" complex.
Components of both ASAP and EJC have been found to function in a wide range of activities on RNA metabolism, including splicing, translation, nonsense-mediated mRNA decay (NMD), and Apoptosis.