What are RBPs?

RNA-binding proteins (RBPs) play a key role in post-transcriptional regulation of gene expression by binding to RNA along various points and at various times. In the model of mRNA metabolism, this interaction occurs concurrently or immediately after transcription as different sets of RBPs bind to the introns and exons of pre-mRNA, through splicing, polyadenylation, mRNA stabilization, nuclear transport, subcellular localization and translation. Since these proteins have the potential to affect the manner and rate of protein synthesis, it is crucial to have a reliable method for identifying and characterizing these RBP/RNA interactions.

What's RIP?

RNA-binding protein immunoprecipitation (RIP) is the RNA analog of the more well-known ChIP application (chromatin immunoprecipitation). RIP can be used to identify specific RNA molecules (of many types) associated with specific nuclear or cytoplasmic binding proteins. These experiments involve immunoprecipitation of endogenously formed complexes of RNA-binding proteins and co-isolation of any RNA species associated with that RNA-binding protein. Purification of these RNA species allows interrogation and identification of mRNAs (and potentially non-coding RNAs associated with them) and can be directly measured using down stream applications including quantitative reverse transcription polymerase chain reaction (qRT-PCR), microarray analysis (RIP-chip) and "deep-sequencing" or 2nd-generation sequencing based platforms (RIP-Seq).

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