45 citations,
April 2009 in “Journal of anatomy” Cat claws stay sharp by shedding their outer layer through microcracks formed during activities.
April 2023 in “The journal of investigative dermatology/Journal of investigative dermatology” Deleting the Hoxc13 gene in frogs shows its crucial role in developing skin structures similar to hair.
36 citations,
November 2019 in “Molecular biology and evolution” Cysteine-rich keratins evolved independently in mammals, reptiles, and birds for hard skin structures like hair, claws, and feathers.
January 2018 in “Stem cell biology and regenerative medicine” The nucleus is key in controlling skin growth and repair by coordinating signals, gene regulators, and epigenetic changes.
72 citations,
December 2018 in “Journal of Experimental Zoology Part B Molecular and Developmental Evolution” Corneous beta-proteins evolved uniquely in reptiles and birds, forming scales, claws, beaks, and feathers.