Nucleosomes Are Well Positioned at Both Ends of Exons

Chromatin structure has an important role in gene regulation. Transcription elongation is closely coupled with the splicing in vivo in eukaryotes. In this paper, nucleosomes near splice sites are predicted for 13 specieses with curvature profile. The results indicate nucleosomes are well positioned at both ends of exons. Nucleosome at 5' end is more conserved than that at 3' end, which probably has a link with alternative splicing. The distance between nucleosome centre and splice site varies among specieses, suggesting an evolution selection. Our analysis reveals that nucleosomes positioned at both ends of exons positioning has a role not only in protecting splice sites, but also in the splicing by placing a barrier at exon ends. Moreover, it is revealed DNA sequence plays an important role in determining nucleosomes at boundary of exons.