Project: Evolution of epidermal cornification proteins
Funded by Austrian Science Fund (FWF): P 28004 (2015/07/01-2019/12/31)
The cornified layer on the surface of the skin and skin appendages suchas hair, feathers, and claws are mechanically resistant protective structures at the interface of the body and the environment. Their protective properties depend on the cross-linking of proteins in epidermal keratinocytes during an evolutionarily conserved processcalled cornification. The formation of disulfide bonds between cysteine residues is an important mechanism of protein cross-linking which is most efficient if proteins contain high numbers of cysteine residues.Accordingly, cysteine-rich proteins are major constituents of humannails and hair.
The aim of this project was to characterize protein components of the cornified epidermis and skin appendages in phylogenetically diverse vertebrates (mammals, reptiles, birds, amphibians) and to investigatethe evolutionary genetics of cysteine-rich epidermal cornification proteins.
We identified genes that encode cysteine-rich keratins and epidermal differentiation complex (EDC) proteins of scales, feathers, and claws.Comparative genomics, molecular phylogenetics and gene expression analyses revealed a broad variety of evolutionary trajectories including diversifying evolution from a common ancestor, convergentevolution at the molecular level, and loss of particular genes duringthe adaptation to a new environment. All results were published underOpen Access in international peer-reviewed journals (cumulative impact factor >50).