Protein sequences bound to mineral surfaces persist into deep time

作者：Beatrice Demarchi, Shaun Hall, Teresa Roncal‐Herrero, Colin L. Freeman, Jos Woolley, Molly K. Crisp, Julie C. Wilson, Anna K. Fotakis, Román Fischer, Benedikt M. Kessler, Rosa Jersie-Christensen, Jesper Velgaard Olsen, James Haile, Jessica E. Thomas, Curtis W. Marean, John E. Parkington, Samantha Presslee, Julia A. Lee‐Thorp, Peter W. Ditchfield, Jacqueline F. Hamilton, Martyn William Ward, Chunting Michelle Wang, Marvin Shaw, Terry Harrison, Manuel Domínguez‐Rodrigo, R. D. E. MacPhee, Amandus Kwekason, Michaela Ecker, Liora Kolska Horwitz, Michael Chazan, Roland Kröger, Jane E. THOMAS‐OATES, John H. Harding, Enrico Cappellini, Kirsty E. H. Penkman, Matthew J. Collins · 发表于：eLife · 年份：2016 · DOI：10.7554/elife.17092 · 被引用次数：285 · 研究领域：Evolution and Paleontology Studies、Paleontology and Evolutionary Biology、Pleistocene-Era Hominins and Archaeology

Proteins persist longer in the fossil record than DNA, but the longevity, survival mechanisms and substrates remain contested. Here, we demonstrate the role of mineral binding in preserving the protein sequence in ostrich (Struthionidae) eggshell, including from the palaeontological sites of Laetoli (3.8 Ma) and Olduvai Gorge (1.3 Ma) in Tanzania. By tracking protein diagenesis back in time we find consistent patterns of preservation, demonstrating authenticity of the surviving sequences. Molecular dynamics simulations of struthiocalcin-1 and -2, the dominant proteins within the eggshell, reveal that distinct domains bind to the mineral surface. It is the domain with the strongest calculated binding energy to the calcite surface that is selectively preserved. Thermal age calculations demonstrate that the Laetoli and Olduvai peptides are 50 times older than any previously authenticated sequence (equivalent to ~16 Ma at a constant 10°C).