A peak for exons | Nature Reviews Genetics

Access through your institution Buy or subscribe Three research teams, working independently, used publicly available high-resolution maps of nucleosome density generated from

high-throughput sequencing data to compare nucleosome positioning to exon and intron structure. Schwartz _et al_. looked at genome-wide nucleosome occupancy data from human T cells,

_Caenorhabditis elegans_ and _Drosophila melanogaster_, and Tilgner _et al_. and Andersson _et al_. used the human and _C. elegans_ data sets. All three papers show that, across species,

exons have significantly higher nucleosome occupancy than introns. The researchers then investigated whether this pattern was determined by the underlying DNA sequence. Exons are known to

have a higher GC content than introns, but they found that GC content _per se_ does not cause higher nucleosome occupancy. Instead, Tilgner _et al_. suggest that the higher GC content of

exons might be the result of selection to maintain nucleosome positioning sequences, which have an above average GC content. Schwartz and colleagues found that pentamers that disfavour

nucleosome binding are depleted within exons but are enriched within the intronic regions that flank exons, including at regions that were previously detected as intronic splicing enhancers.

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calculated during checkout ADDITIONAL ACCESS OPTIONS: * Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support REFERENCES ORIGINAL RESEARCH PAPERS *

Tilgner, H. et al. Nucleosome positioning as a determinant of exon recognition. _Nature Struct. Mol. Biol._ 16, 996–1001 (2009) Article  CAS  Google Scholar  * Schwartz, S. et al. Chromatin

organization marks exon–intron structure. _Nature Struct. Mol. Biol._ 16, 990–995 (2009) Article  CAS  Google Scholar  * Andersson, R. et al. Nucleosomes are well positioned in exons and

carry characteristic histone modifications. _Genome Res._ 17 Aug 2009 (doi:10.1101/gr.092353.109) Article  CAS  PubMed  PubMed Central  Google Scholar  FURTHER READING * Jiang, C. &

Pugh, B. F. Nucleosome positioning and gene regulation: advances through genomics. _Nature Rev. Genet._ 10, 161–172 (2009) Article  CAS  PubMed  Google Scholar  Download references Authors *

Mary Muers View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Muers,

M. A peak for exons. _Nat Rev Genet_ 10, 664–665 (2009). https://doi.org/10.1038/nrg2669 Download citation * Published: 08 September 2009 * Issue Date: October 2009 * DOI:

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