Identification of Transcriptional Regulators That Bind to Long Noncoding RNAs by RNA Pull-Down and RNA Immunoprecipitation.

Long noncoding RNAs (lncRNAs) are RNA transcripts that are at least 200 nucleotides long and lack coding potential, and they have been demonstrated to be involved in a wide range of biological processes. Many lncRNAs, especially those enriched in nucleus, have been found to regulate gene expression at transcriptional level. Regulation of gene transcription by lncRNAs are mainly mediated by transcriptional regulators (TRs) which interact with lncRNAs. LncRNAs can either enhance or suppress TR's activity, which depends on different mechanism and cellular context. RNA pull-down assay followed by RNA immunoprecipitation is a powerful tool to identify and confirm the specific interaction between TRs and lncRNAs. In this chapter, we illustrate how to perform RNA pull-down and RNA immunoprecipitation to identify TRs that interact with lncRNAs using frozen liver tissues.