Figure 1.

Comparison of ESP and PAR–CLIP technologies. Schematics of the workflow for ESP methodology (A) compared with PAR–CLIP (B), as performed by Hafner et al. (39), to illustrate one of the incentives for performing this study. Specifically, the timeline and handling required for both procedures is shown on clock faces, together with the relative amounts of starting cell lysate required, and the complexity of the PAR–CLIP protocol. Typically, RBPs are overexpressed for CLIP protocols. ∗ indicates the use of nucleoside substitution, which can induce a nucleolar stress response and result in cytotoxicity (81, 82). ESP, Exclusion-Based Sample Preparation; PAR–CLIP, photoactivatable ribonucleoside–enhanced crosslinking and immunoprecipitation; RNA-binding protein.