Evidence of preserved collagen in an Early Jurassic sauropodomorph dinosaur revealed by synchrotron FTIR microspectroscopy
Yao-Chang Lee, Cheng-Cheng Chiang, Pei-Yu Huang, Chao-Yu Chung, Timothy D. Huang, Chun-Chieh Wang, Ching-Iue Chen, Rong-Seng Chang, Cheng-Hao Liao & Robert R. Reisz
Nature Communications 8, Article number: 14220 (2017)
Received: 13 December 2015 Accepted: 09 December 2016 Published online:
31 January 2017
Figure 1: Rib fragment (CXPM Z4644) of Lufengosaurus.
Fossilized organic remains are important sources of information because they provide a unique form of biological and evolutionary information, and have the long-term potential for genomic explorations. Here we report evidence of protein preservation in a terrestrial vertebrate found inside the vascular canals of a rib of a 195-million-year-old sauropodomorph dinosaur, where blood vessels and nerves would normally have been present in the living organism. The in situ synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectra exhibit the characteristic infrared absorption bands for amide A and B, amide I, II and III of collagen. Aggregated haematite particles (α-Fe2O3) about 6∼8 μm in diameter are also identified inside the vascular canals using confocal Raman microscopy, where the organic remains were preserved. We propose that these particles likely had a crucial role in the preservation of the proteins, and may be remnants partially contributed from haemoglobin and other iron-rich proteins from the original blood.
We thank ChuanWei Yang of LuFeng County Dinosaur Museum and ShiMing Zhong of ChuXiong Prefecture Museum for their assistance in field work, and Cheng-Chi Chen for help with SR-FTIR experiments and the colleagues in the accelerator operation group at the NSRRC, Taiwan, for optimizing the stability of the infrared synchrotron radiation. Funding was provided by NSRRC, MOE 103G-903-2 through National Central University, MOST 105-2112-M-213-001 (Taiwan) and NSERC (Canada).
National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
Yao-Chang Lee, Cheng-Cheng Chiang, Pei-Yu Huang, Chun-Chieh Wang & Ching-Iue Chen
Department of Optics and Photonics, National Central University, Chung-Li 32001, Taiwan
Yao-Chang Lee, Timothy D. Huang, Rong-Seng Chang & Robert R. Reisz
Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan
Dinosaur Evolution Research Center of Jilin University, Changchun, Jilin 130012, China
Timothy D. Huang & Robert R. Reisz
College of Life Sciences, National Chung Hsing University, Taichung 400, Taiwan
Timothy D. Huang & Robert R. Reisz
Tosun Public Interests Foundation, Taipei 100, Taiwan
Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada L5L 1C6
Robert R. Reisz
Y.-C.L. wrote first draft of the paper, analysed spectral data of SR-FTIR and Raman scattering and constructed SR-FTIR spectral images. C.-C.C. made fossil ultrathin slides; C.-C.C. and R.-S.C. first found red-blood-cell-like particles within the Lufengosaurus rib and proposed their study. P.-Y.H. acquired FTIR spectral data and constructed FTIR images; C.-Y.C. collected the transient absorption images of haematite in the fossil; T.D.H. initiated the organic remains project, provided various fossil specimens and contributed to the manuscript. C.-C.W. helped to acquire three-dimensional tomographic images. C.-I.C. set optical alignment of endstation of IMS and acquired FTIR spectral images; C.-H.L. provided logistical and research support. R.R.R. proposed the study, contributed to manuscript and guided the project.
The authors declare no competing financial interests.
Correspondence to Yao-Chang Lee or Robert R. Reisz.