Figure 1. iCLIP generates fragments that result from either termination or read-through of the RT at the crosslinking site.

Scheme of the iCLIP method (modified from ref. 6). The RNA fragment is covalently bound to the RNA-binding protein (RBP) after ultraviolet irradiation. After immunoprecipitation, the RBP is partially digested by proteinase K and, following RNA linker ligation, the RNA fragment is reverse transcribed. The RT either terminates or reads through at the crosslinking site (red bar) and thus iCLIP libraries can contain both truncated and full-length fragments. Following self-circularization, the complementary DNA is linearized, PCR amplified and deep-sequenced.