The study by König et al. (2011) used individual-nucleotide resolution UV-cross-linking and immunoprecipitation (iCLIP) to investigate the role of heterogeneous nuclear ribonucleoprotein C (hnRNP C) in splicing regulation. iCLIP revealed that hnRNP C binds to uridine tracts with a defined long-range spacing, consistent with the organization of hnRNP particles. The analysis showed that hnRNP particles assemble on both introns and exons but are generally excluded from splice sites. By integrating transcriptome-wide iCLIP data and alternative splicing profiles into an 'RNA map', the researchers determined how the positioning of hnRNP particles affects the inclusion of alternative exons. The high-resolution iCLIP data provided insights into the mechanism of splicing regulation, highlighting the dual role of hnRNP particles in maintaining splicing fidelity by incorporating introns and exons while leaving splice sites accessible to the splicing machinery. The study also demonstrated that hnRNP C binding patterns could predict exon silencing, further supporting the model of position-dependent splicing regulation by hnRNP particles.The study by König et al. (2011) used individual-nucleotide resolution UV-cross-linking and immunoprecipitation (iCLIP) to investigate the role of heterogeneous nuclear ribonucleoprotein C (hnRNP C) in splicing regulation. iCLIP revealed that hnRNP C binds to uridine tracts with a defined long-range spacing, consistent with the organization of hnRNP particles. The analysis showed that hnRNP particles assemble on both introns and exons but are generally excluded from splice sites. By integrating transcriptome-wide iCLIP data and alternative splicing profiles into an 'RNA map', the researchers determined how the positioning of hnRNP particles affects the inclusion of alternative exons. The high-resolution iCLIP data provided insights into the mechanism of splicing regulation, highlighting the dual role of hnRNP particles in maintaining splicing fidelity by incorporating introns and exons while leaving splice sites accessible to the splicing machinery. The study also demonstrated that hnRNP C binding patterns could predict exon silencing, further supporting the model of position-dependent splicing regulation by hnRNP particles.