Practical Considerations for Analyzing Antigene RNAs (agRNAs): RNA Immunoprecipitation of Argonaute

Target validation for small RNAs in cells can be a confusing task wrought with pitfalls and false leads. One technique for validating in vivo targets of small RNAs is immunoprecipitation of target RNAs using antibodies again the RNAi machinery. Antigene RNAs (agRNAs) regulate transcription in human cells using machinery from the RNAi regulatory pathway – namely argonaute proteins. Here we describe a technique for validating targets of agRNAs using RNA immunoprecipitation with antibodies against human argonaute proteins. This technique can be used to detect interactions of argonaute proteins in the cell nucleus with their targets, lowly expressed noncoding RNA transcripts.