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Re: Dinosaur Protein
And, why does DNA not hold up so well?<<<
Some good answers have already made it to the list about the molecular
reasons why DNA is suceptible to more rapid breakdown. As it's a
biology-related mailing list, I wanted to point out that there are
underlying evolutionary reasons for is. As many of you know DNA is not
simply run from front to back through the protein synthesis machinery.
Instead protein synthesis responds to a complex network of hormones and
other intercellular communication, intracellular changes in chemical
makeup, and environmental cues. DNA has to be able to be opened easily
(e.g. unwrapped from histones and the needed portion transcribed), and
this "flexibility" in conformation is synonymous with breaking down
Collagen, on the other hand, is the tough, non-elastic protein in
connective tissue, and has been selected to the opposite selective
pressures the previous several billion years. In order to retain its
shape and hold...whatever it's holding...in place, it needs to not
respond to chemical alterations, and hence has evolved to be relatively
So it really has to be this way, or else organisms as we understand
them would not work. We could even hypothesize that if future
paleontologists are ever working on a very different form of life (that
evolved separately from Earth), that we will again be far more likely
to recover connective tissue proteins, but much less likely to recover
intact whatever molcule is used to store the instruction set for
producing and maintainng an organism.
Wyoming Dinosaur Center
110 Carter Ranch Rd.
Thermopolis, WY 82443
(800) 455-3466 ext. 230
Cell: (307) 921-8333
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