Fig. 2
From: Evidence for a novel overlapping coding sequence in POLG initiated at a CUG start codon
Synonymous site conservation in the POLG coding region for the major vertebrate clades. Clades shown are a. mammals, b. amphibians, c. sauropsids, and d. teleost fish. In each subfigure, the top panel shows the position of 0-frame stop codons in each sequence in the alignment. The following panels show the positions of stop codons in the + 1 and + 2 frames. The blue dots represent stop codons and the grey regions represent alignment gaps. The bottom two panels show the synonymous site conservation analysis, with the brown line showing the ratio of the observed number of synonymous substitutions within a given window to the number expected under a null model of neutral evolution at synonymous sites, and the red line showing the corresponding p-value. The horizontal grey dashed line indicates a p = 0.05 threshold after an approximate correction for multiple testing (namely scaling by [sliding window size]/[POLG ORF length]). All subfigures use a 25-codon sliding window. The stop codon of ORF-Y in mammals is indicated with a black arrow