Which IP technique is used for RNA-protein interaction?
RNA Immunoprecipitation is specialized method for investigating RNA-protein interactions in physiological context. Cells are lysed in RNase-inhibited buffer or crosslinked with formaldehyde or UV to preserve ribonucleoprotein complexes. Lysate is immunoprecipitated with antibody against RNA-binding protein such as HuR, FMRP or Argonaute. Co-precipitated RNA is isolated, reverse transcribed and analyzed via RT-PCR or RNA sequencing. This strategy preserves association between protein and target mRNA, lncRNA or miRNA. Chromatin Immunoprecipitation targets DNA, Co-IP targets protein partners, thus RIP remains essential for post-transcriptional regulation studies.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.