Analyses of Soft Tissue from Tyrannosaurus rex Suggest the Presence of Protein. 2007. Science 316: 277 - 280
Abstract: We present evidence from multiple analyses of Tyrannosaurus rex (MOR 1125) fibrous cortical and medullary tissues remaining after demineralization that support the preservation of collagen I, the main organic component of bone, in low concentrations in these tissues. We propose a possible chemical pathway that may contribute to this preservation. The presence of endogenous protein in dinosaur bone may validate hypotheses about evolutionary relationships, rates and patterns of molecular change and degradation, and chemical stability of molecules over time.Read one of the press releases, and:
Protein Sequences from Mastodon and Tyrannosaurus Rex Revealed by Mass Spectrometry. 207. J. M. Asara, et al. Science 316: 280-285.
Abstract: Fossilized bones from extinct taxa harbor the potential for obtaining protein or DNA sequences that could reveal evolutionary links to extant species. We used mass spectrometry to obtain protein sequences from bones of a 160,000- to 600,000-year-old extinct mastodon (Mammut americanum) and a 68-million-year-old dinosaur (Tyrannosaurus rex). The presence of T. rex sequences indicates that their peptide bonds were remarkably stable. Mass spectrometry can thus be used to determine unique sequences from ancient organisms from peptide fragmentation patterns, a valuable tool to study the evolution and adaptation of ancient taxa from which genomic sequences are unlikely to be obtained.