Figure 6
From: Convergent evolution of cysteine-rich proteins in feathers and hair
Differences in exon-intron structures and gene loci argue against common ancestry of EDCRP and KRTAPs. The exon-intron structures of EDCRP and KRTAP genes as well as their locations in the EDC and in the type 1 keratin gene cluster, respectively, are depicted schematically. Grey shading marks the coding region within exons. The inferred gene composition of ancestral genomes is shown below the schematics of the modern genomes. It remains uncertain whether the ancestral gene of avian and lizard EDCRPs was already cysteine (C)-rich.