Science Advisor
Gold Member
- 2,853
- 12,702
Science News article here.
Keratins are structural proteins in skin, claws, nails, and hair (ectodermal derivatives embryologically speaking).
They have evolved through many gene duplications, deletions and partial deletions, and point mutations through vertebrate evolution.
Their evolution has been mapped by putting the various forms of living animals on a vertebrate phylogenetic (evolutionary) tree and then inferring their presence in now extinct ancestors.
We (people) have alpha-keratins while birds, crocodiles, and reptiles have mostly beta-keratins which are hard and stiff. They are used in beaks and claws, and feathers.
Bird feather keratin has lost certain amino acid sequences that let's the keratin become more flexible (good for feathers).
Researchers have now made antibodies to parts of the keratin protein that can distinguish between the different kinds of keratin protein. These antibodies were used on some very well preserved dinosaur fossils to identify the kind of keratin present in ancient bird/dinosaur feathers, confirming that they had some flexible beta-keratin 160 million years ago!
Just recently, the preservation of proteins in fossils that old was highly controversial.
Keratins are structural proteins in skin, claws, nails, and hair (ectodermal derivatives embryologically speaking).
They have evolved through many gene duplications, deletions and partial deletions, and point mutations through vertebrate evolution.
Their evolution has been mapped by putting the various forms of living animals on a vertebrate phylogenetic (evolutionary) tree and then inferring their presence in now extinct ancestors.
We (people) have alpha-keratins while birds, crocodiles, and reptiles have mostly beta-keratins which are hard and stiff. They are used in beaks and claws, and feathers.
Bird feather keratin has lost certain amino acid sequences that let's the keratin become more flexible (good for feathers).
Researchers have now made antibodies to parts of the keratin protein that can distinguish between the different kinds of keratin protein. These antibodies were used on some very well preserved dinosaur fossils to identify the kind of keratin present in ancient bird/dinosaur feathers, confirming that they had some flexible beta-keratin 160 million years ago!
Just recently, the preservation of proteins in fossils that old was highly controversial.