Poster abstracts
Poster number 127 submitted by Vikas Kaushik
Deciphering the principles of RNA binding specificity of multi-domained proteins using non-canonical amino acids
Vikas Kaushik (Biochemistry and Molecular Biology, Saint Louis University, School of Medicine), Rahul Chadda (Biochemistry and Molecular Biology, Saint Louis University, School of Medicine), Abhinav Vayyeti, Sonia Patel (Biochemistry and Molecular Biology, Saint Louis University, School of Medicine), Richard Cooley (Biochemistry and Biophysics, Oregon State University), Ryan Mehl (Biochemistry and Biophysics, Oregon State University), Edwin Antony (Biochemistry and Molecular Biology, Saint Louis University, School of Medicine)
Abstract:
RNA binding proteins (RBPs) regulate the life cycle of RNA by recognizing the correct substrate and appropriately directing their nuclear export, translation/degradation, and intracellular localization of target transcripts. Here, we focus on the family of multi-domained onco-fetal RNA binding Insulin-like Growth Factor 2 mRNA-Binding Proteins (IGF2BP or IMP). IMP1, IMP2, and IMP3 are the three orthologous members in this family and are structurally composed of six RNA binding domains (RBDs): four KH and two RRM domains. While structurally homologous, they recognize several hundred individual transcripts and define their cellular fates. Yet, how they impart functional specificity is poorly understood. We propose that individual RBDs are differentially regulated and positioned to drive specific outcomes. To test this hypothesis, we use non-canonical amino acid (ncAA) tools to probe the dynamics of individual RBDs while keeping the full-length protein intact. Here, results from positioning a site-specific fluorophore within a single RBD and site-specific phospho-Ser in IMP1 and IMP3 will be presented.
Keywords: IGF2BP, RBDs, ncAA