for National Geographic News
The fossilized leg of an 80-million-year-old duck-billed dinosaur has yielded the oldest known proteins preserved in soft tissue—including blood vessels and other connective tissue as well as perhaps blood cell proteins—a new study says.
The research was led by the team behind the controversial 2007 discovery of protein from similar soft tissues in 68-million-year-old Tyrannosaurus rex bones.
"It was not a one-hit wonder," said John Asara of Harvard Medical School, who led the protein-sequence analysis.
(See a prehistoric time line)
The proteins were recovered from a hadrosaur femur that had been encased in sandstone, which appears to prevent complete tissue degradation, Asara said.
Preliminary microscopic analysis revealed structures resembling blood vessels, cells, and collagen, he noted.
Those initial speculations were confirmed by applying antibodies to the tissue that are known to react with proteins. The tests suggested the presence of collagen and other proteins, including hemoglobin, the protein in red blood cells.
Dinosaur Blood Cells?
The hints of hemoglobin remain speculative and are not covered in the new, peer-reviewed study, which appears in today's issue of the journal Science.
Some scientists suspect the hemoglobin is a contaminant.
If it's not a contaminant, "it is much bigger news than [the confirmed discoveries of blood vessels and other connective tissues in] this paper," said Pavel Pevzner, a computational biologist at the University of California, San Diego, who was not involved in the new research.
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