Response to Comment on “Protein Sequences from Mastodon and Tyrannosaurus rex Revealed by Mass Spectrometry”
نویسندگان
چکیده
We sequenced six endogenous collagen peptides from Tyrannosaurus rex bone fragments using mass spectrometry. Five sequences match birds, but only two match amphibians, supporting dinosaur-bird relationships. Buckley et al. reinterpret and misinterpret our data and question sequence authenticity, but they used a suboptimal phylogenetic algorithm to analyze only a subset of reported sequences and they suggest analyses that are less sensitive and less specific than mass spectrometry. We disagree and use data to explain.
منابع مشابه
Protein sequences from mastodon and Tyrannosaurus rex revealed by mass spectrometry.
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 ...
متن کاملComment on "Protein sequences from mastodon and Tyrannosaurus rex revealed by mass spectrometry".
We used authentication tests developed for ancient DNA to evaluate claims by Asara et al. (Reports, 13 April 2007, p. 280) of collagen peptide sequences recovered from mastodon and Tyrannosaurus rex fossils. Although the mastodon samples pass these tests, absence of amino acid composition data, lack of evidence for peptide deamidation, and association of alpha1(I) collagen sequences with amphib...
متن کاملMolecular phylogenetics of mastodon and Tyrannosaurus rex.
We report a molecular phylogeny for a nonavian dinosaur, extending our knowledge of trait evolution within nonavian dinosaurs into the macromolecular level of biological organization. Fragments of collagen alpha1(I) and alpha2(I) proteins extracted from fossil bones of Tyrannosaurus rex and Mammut americanum (mastodon) were analyzed with a variety of phylogenetic methods. Despite missing sequen...
متن کاملAnalyses of soft tissue from Tyrannosaurus rex suggest the presence of protein.
We performed multiple analyses of Tyrannosaurus rex (specimen MOR 1125) fibrous cortical and medullary tissues remaining after demineralization. The results indicate that collagen I, the main organic component of bone, has been preserved in low concentrations in these tissues. The findings were independently confirmed by mass spectrometry. We propose a possible chemical pathway that may contrib...
متن کاملCannibalism in Tyrannosaurus rex
BACKGROUND Tyrannosaurus rex was one of the largest terrestrial carnivores of all time, and consequently its ecology and diet have been the focus of much discussion. However, there is little direct evidence of diet or feeding habits in this species. METHODOLOGY/PRINCIPAL FINDINGS Examination of museum collections has revealed four specimens of Tyrannosaurus rex that bear tooth marks made by l...
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