Volume 13, Issue 24, Pages 2170-2174 (December 2003) Evidence of Splice Signal Migration from Exon to Intron during Intron Evolution  Alexander V. Sverdlov, Igor B. Rogozin, Vladimir N. Babenko, Eugene V. Koonin  Current Biology  Volume 13, Issue 24, Pages 2170-2174 (December 2003) DOI: 10.1016/j.cub.2003.12.003

Figure 1 Information Content in the Regions Surrounding Splice Sites of Old and New Introns (A) All analyzed introns pooled together. (B) Introns separated by phases. (C) Difference in information content between old and new introns of different phases. The break between the sequences surrounding the donor and acceptor splice eliminates most of the intron sequence. Vertical axis, information content in bits. Current Biology 2003 13, 2170-2174DOI: (10.1016/j.cub.2003.12.003)

Figure 2 The Nucleotide Composition (Sequence LOGOs) of the Positions Adjacent to Splice Sites in Old and New Introns Vertical axis, information content in bits. Current Biology 2003 13, 2170-2174DOI: (10.1016/j.cub.2003.12.003)