Distribution of dinucleotide exclusion zones

Copyright information:Taken from "A class of human exons with predicted distant branch points revealed by analysis of AG dinucleotide exclusion zones"Genome Biology 2006;7(1):R1-R1.Published online 13 Jan 2006PMCID:PMC1431707.Copyright © 2006 Gooding et al.; licensee BioMed Central Ltd. Shown is the distribution of dinucleotide exclusion zones (mod-EZ) upstream of 49,876 human exons (having excluded cases in which the intron was less that 350 nucleotides). Y-axis: log [number of exons]. X-axis: log [size of mod-EZ]. Data are normalized to give a probability density function, which gives the probability that an exon chosen at random will have an exclusion zone of a given size; the area under each curve is 1. Blue lines: first exclusion zone (mod-EZ), measured from -25 (relative to the 3' splice site) to the first upstream occurrence of the particular dinucleotide (see Materials and methods). Red lines: second exclusion zone (mod-EZ), measured from -25 relative to the end of the mod-EZ. AG shows the largest variance between mod-EZand mod-EZ. Data was sorted into bins of logarithmically increasing widths rendered discrete (bin width 10 at ~100; bin width 100 at ~1,000), with final bin counts divided by bin width and by the total number of exons, followed by application of a three-point averaging filter to produce the given plots. See Materials and methods for full details.