Fossils of Extinct Giant Beaver Open New Doors in the Study of Ancient Proteins

A new study involving a fossil of an extinct species of giant beaver dug up 170 years ago in central New York has provided some new insights in the field of paleoproteomics, the study of ancient proteins.

Previously, researchers studying ancient proteins rely on fossils that were dug up for that purpose. However, the new study, published in the journal Proceedings of the Royal Society B, used a giant beaver skull that was collected in 1845 and has been housed at the New York State Museum.

"In paleoproteomics we've generally looked at specimens collected recently and carefully stored in climate-controlled conditions. In this case, we're looking at a specimen that sat on a shelf collecting dust for most of its life," explained Timothy Cleland, a postdoctoral researcher formerly at Rensselaer Polytechnic Institute and now at the University of Texas-Austin, in a statement.

For the study, researchers extracted proteins from the skull of the giant beaver belonging to the species Castoroides ohioensis. Using mass spectrometry analysis, the researchers search for proteins, chains of amino acids assembled from instructions encoded in DNA that perform a wide variety of functions in living organisms.

The researchers then detected many samples of collagen 1 in the protein they extracted. Collagen 1 is the most common protein in bone. The researchers also found post-translational modifications, chemical changes on the surface of the protein that are not defined by DNA.

The discovery of post-transitional modifications is very significant because has little precedent in the emerging field of paleoproteomics.

According to Cleland, studying the post-translational modifications of certain proteins can provide further understanding on how organisms manipulate that protein so it can function better.

"Now imagine if we were able to build up a database of post-translational modification to ancient organisms, we could begin to make inferences about evolutionary changes, or use them in protein engineering to look at how function in the ancient protein compares to that same protein in living animals." Cleland said in a press release.