Reports in recent years of soft dinosaur tissue from fossil bones of a T. rex and a duck-billed hadrosaur elicited skepticism from the scientific community. But a new analysis of the bits of protein that survived supports claims of ancient origins.
The same kinds of collagen building blocks extracted from the dinosaur fossils are found in sheltered, physically protected areas of collagen fibers in rats and humans, researchers report online June 8 in PLoS ONE.
Collagen is best known for its role in stretchy connective tissue such as tendons, ligaments and skin, but it’s also the primary protein in bone. At large scales, collagen fibers look pretty much the same: a triple helix of tightly twisted cords that together are further twisted and packed into larger ropes. But in any one section of the molecule the building blocks are different. The amino acids strung together to make the protein aren’t the same in all parts of a collagen fiber, and those differences dictate various interactions between the molecule and its neighborhood, says study coauthor Joseph Orgel of the Illinois Institute of Technology in Chicago.