Signal sequences in intron equivalents
The 5' and 3' ends of each intron are
marked with GU and AG dinucleotide sequences;
a short tract of poly-pyrimidines (C or T)
also occurs near the 3' end ahead of the AG singal.
[Note: exons and introns occur
in the DNA sequence as expressed and intervening
sequences: hnRNA products transcribed off the DNA
template strand include exon and intron equivlaents.
Figure © 2012 TA Brown, Introduction
to Genetics (1st ed.); additional
text © 2014 by Steven M. Carr