Cornified Epithelial Teeth of Jawless Vertebrates Contain Proteins Similar to Keratin-Associated Proteins of Mammalian Skin Appendages

May 2025 in “ Journal of Developmental Biology ”

Attila Placido Sachslehner, David Parry, Leopold Eckhart

keratin-associated proteins KRTAP keratin-associated protein-like KRTAPL mass spectrometry-based proteomics cysteine tyrosine keratin proteomics

Studysummary This study reports that KRTAP-like proteins, which resemble keratin-associated proteins found in mammals, are also present in the cornified teeth of various lamprey species, suggesting these proteins may serve similar functions in skin appendages across different vertebrates despite independent evolutionary origins.

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The study examines the presence of keratin-associated protein-like (KRTAPL) proteins in the cornified epithelial teeth of jawless vertebrates, specifically lampreys, using mass spectrometry-based proteomics. These proteins share similarities with mammalian keratin-associated proteins (KRTAPs) found in hair and nails, such as high cysteine and tyrosine content, but differ in gene structure, having two exons instead of one. The research suggests that these proteins evolved through convergent evolution, indicating an evolutionary parallel in the development of structural proteins across different species. The study highlights the need for further research into the expression and function of KRTAPLs in lampreys.

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