RNA Immunoprecipitation Assay to Determine the Specificity of SRSF3 Binding to Nanog mRNA.

Mammalian cells express hundreds of RNA binding proteins (RBPs) that are essential regulators of RNA metabolism. RBP activity plays a central role in the control of gene expression programs and identification of RNA-protein interactions is critical for comprehensive understanding of gene regulation in cells. In recent years, various tools and techniques to identify these RNA-protein interactions have been developed. Among those, RNA immunoprecipitation is a precise and powerful assay that can be used to establish the physical interaction of an individual RBP with its target RNAs in vivo. Here, we describe a quantitative method for determining RNA-protein interactions using RNA immunoprecipitation (RNA-IP) assay in mouse embryonic stem cells carrying ectopically expressed mutant constructs. This protocol is reliable and easily adaptable to identify the interactions of endogenous or ectopically expressed RNAs and proteins.