Abstract
The evolutionary relationships of extinct species are ascertained primarily through the analysis of morphological characters. Character inter-dependencies can have a substantial effect on evolutionary interpretations, but the developmental underpinnings of character inter-dependence remain obscure because experiments frequently do not provide detailed resolution of morphological characters. Here we show experimentally and computationally how gradual modification of development differentially affects characters in the mouse dentition. We found that intermediate phenotypes could be produced by gradually adding ectodysplasin A (EDA) protein in culture to tooth explants carrying a null mutation in the tooth-patterning gene Eda. By identifying development-based character inter-dependencies, we show how to predict morphological patterns of teeth among mammalian species. Finally, in vivo inhibition of sonic hedgehog signalling in Eda null teeth enabled us to reproduce characters deep in the rodent ancestry. Taken together, evolutionarily informative transitions can be experimentally reproduced, thereby providing development-based expectations for character-state transitions used in evolutionary studies.
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References
Luo, Z. X., Cifelli, R. L. & Kielan-Jaworowska, Z. Dual origin of tribosphenic mammals. Nature 409, 53–57 (2001)
Meng, J. & Wyss, A. R. The morphology of Tribosphenomys (Rodentiaformes, Mammalia): Phylogenetic implications for basal Glires. J. Mamm. Evol. 8, 1–71 (2001)
Asher, R. J. et al. Stem lagomorpha and the antiquity of Glires. Science 307, 1091–1094 (2005)
O'Leary, M. A. et al. The placental mammal ancestor and the post-K-Pg radiation of placentals. Science 339, 662–667 (2013)
Kluge, A. G. & Farris, J. S. Quantitative phyletics and the evolution of anurans. Syst. Zool. 18, 1–32 (1969)
Felsenstein, J. Maximum-likelihood and minimum-steps methods for estimating evolutionary trees from data on discrete characters. Syst. Zool. 22, 240–249 (1973)
Doyle, J. J. Trees within trees: genes and species, molecules and morphology. Syst. Biol. 46, 537–553 (1997)
O’Keefe, F. R. & Wagner, P. J. Inferring and testing hypotheses of cladistic character dependence by using character compatibility. Syst. Biol. 50, 657–675 (2001)
Wake, D. B. Phylogenetic implications of ontogenetic data. Geobios 22 (supp. 2). 369–378 (1989)
Kangas, A. T., Evans, A. R., Thesleff, I. & Jernvall, J. Nonindependence of mammalian dental characters. Nature 432, 211–214 (2004)
Luo, Z.-X. Transformation and diversification in early mammal evolution. Nature 450, 1011–1019 (2007)
Polly, P. D. Developmental dynamics and G-matrices: can morphometric spaces be used to model evolution and development? Evol. Biol. 35, 83–96 (2008)
Rice, S. H. Theoretical approaches to the evolution of development and genetic architecture. Ann. NY Acad. Sci. 1133, 67–86 (2008)
Salazar-Ciudad, I. & Marin-Riera, M. Adaptive dynamics under development-based genotype-phenotype maps. Nature 497, 361–364 (2013)
Grüneberg, H. Genes and genotypes affecting the teeth of the mouse. J. Embryol. Exp. Morphol. 14, 137–159 (1965)
Harfe, B. D. et al. Evidence for an expansion-based temporal Shh gradient in specifying vertebrate digit identities. Cell 118, 517–528 (2004)
Jernvall, J., Keränen, S. V. E. & Thesleff, I. Evolutionary modification of development in mammalian teeth: quantifying gene expression patterns and topography. Proc. Natl Acad. Sci. USA 97, 14444–14448 (2000)
Gaide, O. & Schneider, P. Permanent correction of an inherited ectodermal dysplasia with recombinant EDA. Nature Med. 9, 614–618 (2003)
Harjunmaa, E. et al. On the difficulty of increasing dental complexity. Nature 483, 324–327 (2012)
Arthur, W. Evolution: a Developmental Approach (Wiley-Blackwell, 2011)
Salazar-Ciudad, I. & Jernvall, J. A computational model of teeth and the developmental origins of morphological variation. Nature 464, 583–586 (2010)
Butler, P. M. Early trends in the evolution of tribosphenic molars. Biol. Rev. Camb. Philos. Soc. 65, 529–552 (1990)
Osborn, J. W. & Crompton, A. W. The evolution of mammalian from reptilian dentitions. Breviora 399, 1–18 (1973)
Wessels, W. Miocene rodent evolution and migration: Muroidea from Pakistan, Turkey and North Africa. Geol. Ultraiectina 307, 1–290 (2009)
López Antoñanzas, R. First Potwarmus from the Miocene of Saudi Arabia and the early phylogeny of murines (Rodentia: Muroidea). Zool. J. Linn. Soc. 156, 664–679 (2009)
Van Valkenburgh, B. Major patterns in the history of carnivorous mammals. Annu. Rev. Earth Planet. Sci. 27, 463–493 (1999)
Evans, A. R., Wilson, G. P., Fortelius, M. & Jernvall, J. High-level similarity of dentitions in carnivorans and rodents. Nature 445, 78–81 (2007)
Santana, S. E., Strait, S. & Dumont, E. R. The better to eat you with: functional correlates of tooth structure in bats. Funct. Ecol. 25, 839–847 (2011)
Luo, Z. X., Ji, Q. & Yuan, C. X. Convergent dental adaptations in pseudo-tribosphenic and tribosphenic mammals. Nature 450, 93–97 (2007)
Kavanagh, K. D., Evans, A. R. & Jernvall, J. Predicting evolutionary patterns of mammalian teeth from development. Nature 449, 427–432 (2007)
Jacob, F. Evolution and tinkering. Science 196, 1161–1166 (1977)
Cho, S.-W. et al. Interactions between Shh, Sostdc1 and Wnt signaling and a new feedback loop for spatial patterning of the teeth. Development 138, 1807–1816 (2011)
Gomes Rodrigues, H. G. et al. Roles of dental development and adaptation in rodent evolution. Nat. Commun. 4, 2504 (2013)
Van Valen, L. An analysis of developmental fields. Dev. Biol. 23, 456–477 (1970)
Goswami, A. & Polly, P. D. in Carnivoran Evolution: New Views on Phylogeny, Form, and Function (eds Goswami, A. & Friscia, A. ) 141–164 (Cambridge Univ. Press, 2010)
Bhullar, B.-A. et al. Birds have paedomorphic dinosaur skulls. Nature 487, 223–226 (2012)
Närhi, K. & Thesleff, I. Explant culture of embryonic craniofacial tissues: analyzing effects of signaling molecules on gene expression. Methods Mol. Biol. 666, 253–267 (2010)
Mauldin, E. A., Gaide, O., Schneider, P. & Casal, M. L. Neonatal treatment with recombinant ectodysplasin prevents respiratory disease in dogs with X-linked ectodermal dysplasia. Am. J. Med. Genet. 149A, 2045–2049 (2009)
Wilson, G. P. et al. Adaptive radiation of multituberculate mammals before the extinction of dinosaurs. Nature 483, 457–460 (2012)
Hammer, Ø., Harper, D. A. T. & Ryan, P. D. PAST: paleontological statistics software package for education and data analysis. Pal. Electron. 4, http://palaeo-electronica.org/2001_1/past/issue1_01.htm (2001)
Fliniaux, I., Mikkola, M. L., Lefebvre, S. & Thesleff, I. Identification of dkk4 as a target of Eda-A1/Edar pathway reveals an unexpected role of ectodysplasin as inhibitor of Wnt signalling in ectodermal placodes. Dev. Biol. 320, 60–71 (2008)
Yauch, R. L. et al. A paracrine requirement for hedgehog signalling in cancer. Nature 455, 406–410 (2008)
Schindelin, J. et al. Fiji: an open-source platform for biological-image analysis. Nature Methods 9, 676–682 (2012)
Acknowledgements
We thank M. Fortelius, J. Eronen, I. Thesleff, P. Munne for discussions; S. Alto, M. Mäkinen, R. Santalahti, R. Savolainen, and M. Christensen for technical assistance; P. Schneider for the Fc-EDA-A1-protein; F. de Sauvage for HhAntag compound; Hou Yemao for tomography; and the Finnish Museum of Natural History (Helsinki, Finland), Museum of Natural History (Stockholm, Sweden), and Museum für Naturkunde (Berlin, Germany) for specimen loans. This work was supported by the Academy of Finland to J.J., M.M., I.S.-C., R01-DE021420 (NIH/NIDCR) and an NIH Director’s New Innovator Award DP2-OD007191 to O.D.K., an Australian Research Council Future Fellowship to A.R.E, and the Major Basic Research Projects (2012CB821904) of MST to Z.-Q.Z. Data are presented in the Supplementary and Extended Data Tables, available in the MorphoBrowser database (http://morphobrowser.biocenter.helsinki.fi/) and from the authors, and models can be accessed at (http://www.biocenter.helsinki.fi/bi/evodevo/toothmaker.html).
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E.H., J.J. and O.D.K. designed the project and wrote the initial manuscript. E.H. and E.R. performed culturing experiments and K.S. mouse experiments. E.H., E.R., A.K. and J.J. performed measurements and prepared images. I.J.C., A.R.E. and J.J. analysed evolutionary data. I.S.-C. constructed the computational model and T.H. the ToothMaker. M.L.M., Z.-Q.Z. provided materials, observations and scientific interpretations. O.D.K. and J.J. coordinated the study. All authors discussed the results and provided input on the manuscript.
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Extended data figures and tables
Extended Data Figure 1 Primary enamel knot size predicts cusp number.
Size of the primary enamel knot (day 2) and cusp number (day 7) for Eda null, Eda null + 10 ng ml−1 EDA, Eda null + 50 ng ml−1 EDA, and wild-type teeth. Reduced major axis regression for square root of µm2 are 0.0533 x −0.791, r2 = 0.613, P < 0.0001, n = 46. Enamel knot size does not increase substantially with higher EDA concentrations.
Extended Data Figure 2 The ToothMaker modelling interface and morphodynamic model of tooth development.
The model parameters can be changed manually or scanned automatically (Options-menu). For descriptions of parameters, see Methods. The figures illustrate the growth factor concentration (secreted from the enamel knots) showing the future cusp areas. Initial activator concentration (Ina) is not used in the model. The model can be downloaded at (http://www.biocenter.helsinki.fi/bi/evodevo/toothmaker.html).
Extended Data Figure 3 Scanning parameter space to produce gradual changes.
a, Parameters producing variation in cusp number were scanned at 10 percent intervals up to 90 percent change from the wild-type (WT) mouse. Growth factor domains, produced by enamel knots, were used to tabulate cusps numbers (threshold = 0.04). b, Simulated teeth show the minimum number of cusps that can be produced by changing each parameter. Only parameter Act produced single-cusped morphology. Plus and minus signs after each parameter denote to the direction of parameter change that produced a decrease in cusp number. Act = activator auto-activation, Da = activator diffusion, Int = inhibitor production threshold, Inh = Activator inhibition by inhibitor, Di = inhibitor diffusion, Set = growth factor production threshold, Sec = growth factor secretion rate, Ds = growth factor diffusion, Dff = differentiation rate, Egr = epithelial proliferation rate, Mgr = mesenchymal proliferation rate. All simulations were run for a fixed number of iterations (14,000).
Extended Data Figure 4 Simulating EDA effects.
a, Simulated shapes produced by changing the activator parameter (Act) from 0.1 to 1.6 at 0.1 interval. b, The size of inhibitor domain (at arbitrary threshold 0.85) at iteration 1,000 and corresponding cusp number at iteration 14,000 approximates the relationship between primary enamel knot size and cusp number in real teeth.
Extended Data Figure 5 Simulating reduction of inhibition in Eda null teeth.
Reducing activator inhibition by inhibitor (Inh) or diffusion of inhibitor (Di) results in formation of multiple cusps in simulated Eda null molar. The effects are variable depending on the parameter values, and the lability of the system appears to be corroborated in the in vitro experiments.
Extended Data Figure 6 Rescuing cusps in Eda null teeth by inhibiting SHH.
Eda null teeth cultured with SHH antagonist show variable morphologies with tightly packed cusps (arrowheads). In addition, in roughly half of the cases (n = 4 of 11 teeth) portions of the first molar appear to form from the fusion with the developing second molar (two bottom rows). Scale bar, 500 µm.
Extended Data Figure 7 In vivo inhibition of SHH in Eda null embryos causes the formation of separate cusps without crests.
Obliquely anterior views and tomography sections (along the plane of the dotted line) of second molars show the lack of a crest (metalophid, arrowheads) in treated Eda null and Tribosphenomys minutus (V10775). Enamel in sections shown in blue colour except in Tribosphenomys fossil which did not allow segmentation of enamel due to high degree of mineralization. Scale bar, 500 µm.
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Harjunmaa, E., Seidel, K., Häkkinen, T. et al. Replaying evolutionary transitions from the dental fossil record. Nature 512, 44–48 (2014). https://doi.org/10.1038/nature13613
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DOI: https://doi.org/10.1038/nature13613
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