Sequence logos showing the nucleotide bias around the donor site of 5'UTR, CDS and 3'UTR introns. The x-axis refers to bases from the beginning of the intron, letter heights reflect the nucleotide bias at each position. Only 5 nucleotides of exon and 25 nucleotides of intron sequence at the donor site were included in the sequence logo as deviation of the nucleotide usage from background levels is not apparent outside these regions.
Chung et al. BMC Genomics 2006 7:120 doi:10.1186/1471-2164-7-120