Mary Schweitzer, PhD, professor of biology at North Carolina State University, will present her work on refining methods to extract and responsibly use dinosaur proteins at the American Association of Anatomists annual meeting during the Experimental Biology 2017 meeting, to be held April 22-26 in Chicago.
“When you think about it, it is the message of DNA — the proteins — that are actually the stuff on which natural selection works,” said Schweitzer. “The sequences of proteins can be used to generate ‘family trees’ of organisms, just like DNA. But modifications to proteins, which are not found in DNA and can’t be reliably predicted from DNA sequence alone, can tell us how a protein functioned, because the function of a protein is determined by its 3-D structure.”
For example, if you find a proline amino acid with an extra OH (oxygen + hydrogen) group attached, you can be almost certain you have collagen, the stuff that holds together skin and other connective tissues throughout the body. From the standpoint of function and evolutionary fitness, changes in DNA over time don’t really matter unless the protein changes; as a result, studying changes in proteins over time can yield richer information about evolution than studying DNA alone, Schweitzer explained.
Proteins also can yield clues about the age of a sample or about the environment in which an animal lived or was buried. Researchers are also keen to understand what makes some proteins break down while others persist for eons. Conveniently, Schweitzer and others have found that proteins (or at least some types of them) are more likely to remain stable over tens of millions of years than DNA is, making them low-hanging fruit for extracting new information from old bones.