Abstracts BIOMIN XV: 15th International Symposium on Biomineralization 9–13 September 2019 • Munich, Germany 1. Keynote lectures (K1 – K8) ................................................................................................................. 2 2. Talks (T1 – T89) ................................................................................................................................... 4 3. Posters (P1 – P107) ............................................................................................................................. 31 Design/Layout Layout: www.conventus.de Editorial Deadline: 31 August 2019 1 K 1 K 3 On ion transport and concentration toward mineral formation Getting to the roots of apatite-based biomineralization of dental in sea urchin larvae hard tissues: from Conodonts and Cichlids to related Keren Kahi1, Neta Varsano1, Andrea Sorrentino2, Eva Pereiro2, Peter Rez3, bioinspired materials Steve Weiner1 and Lia Addadi*1 Elena V. Sturm*1 (née Rosseeva) 1Department of Structural Biology, Weizmann Institute of Science, Rehovot, 1Physical Chemistry, Zukunftskolleg, University of Konstanz, Konstanz, Israel Germany 2ALBA Synchrotron Light Source, MISTRAL Beamline−Experiments Division, Barcelona, Spain Chordates and especially vertebrates represent the most highly advanced and 3Department of Physics, Arizona State University, Tempe, AZ, USA complex group of organisms. The formation of their hierarchical apatite- organic based hard tissues is evolutionary optimized and exhibits high During mineralized tissue formation, organisms are faced with a major structural complexity on various length scales and amazing mechanical problem in ion transport and concentration. Suffice it to consider that marine performance. The major objective of our research is to explore the animals must concentrate calcium by >4 orders of magnitude relative to its biomineralization processes involved in the formation of dental (and dental- concentration in sea water to deposit calcite or aragonite minerals. Sea urchin like) apatite-based hard tissues of earliest and modern vertebrates. larvae are good model organisms for studying ion processing during skeleton Specifically, in my presentation I will focus on the detailed characterization formation, because of the extensive knowledge accumulated on the processes of morphology-structure-composition-property relationships of hard tissues related to mineral deposition. Sea urchin larvae have endoskeletons of feeding apparatus of Conodonts and Cichlid Fishes. We elaborate and composed of two calcitic spicules, deposited by primary mesenchymal combine exciting evolutionary model systems with cutting-edge spicule-forming cells (PMCs). PMCs take up seawater through spectroscopy, microscopy and diffraction techniques to analyze the endocytosis1 into a complex network of vacuoles. Within the PMCs, calcium structural, chemical and morphogenetic basis of the dental hard tissue ions are translocated from the seawater vacuoles to various organelles and biomineralization process. Our new understanding of dentical and tooth vesicles where they accumulate, and subsequently precipitate as an structure in Conodont and Cichlids could also advance strategies for amorphous calcium carbonate (ACC). The amorphous precipitates are finally synthesizing bioinspired and biomimetic materials and deepen our translocated to the spicule, where they crystallize. knowledge of their morphogenesis process. We address the question of the form in which calcium ions are stored in different locations in the cell, whether dissolved or solid and in which K 4 structural phase. In order to locate and characterize calcium content in Coral Biomineralization: linking pieces of the puzzle individual vesicles we performed cryo-soft X-ray microscopy (cryo-SXM) Sylvie Tambutté*1 on dispersed PMCs. The presence of concentrated calcium ions was detected 1Department of Marine Biology, Centre Scientifique de Monaco, Monaco by imaging the cells in the energy range before and after the calcium L- absorption edges. We characterized the chemical environment of the calcium Coral biomineralization is the process that leads to the formation of a calcium ions using X-ray absorption spectroscopy. We observe hundreds of particles carbonate exoskeleton. As for other biominerals, two essential questions are: containing Ca in each PMC. The particles are composed of different forms What do we know about the control of coral biomineralization? How can we of highly disordered phases of calcium salts, presumably carbonate. We also link biological control with physico-chemical processes? I will show how developed methods for quantitative evaluation of calcium ion concentrations. studies performed at the Centre Scientifique de Monaco since the 90’s have We observed concentrations diluted relative to ACC (19M), but concentrated provided insight into the coral biomineralization process from the whole relative to sea water (10mM). The spectroscopic and analytical data thus organism to the gene by combining molecular and physiological approaches. together indicate a transition through a series of amorphous calcium I will present how data obtained from experiments conducted in different carbonate phases in the low molar concentration range. These data shed light coral compartments: the tissues, the extracellular calcifying medium and the on the intracellular transport and concentration pathways of calcium ions in skeleton can be linked together and can help in deciphering where and how PMCs. This may well be relevant to other organisms, and thus lead to a biological control occurs. More specifically, I will present 1) the deeper understanding of biogenic mineral formation. measurements of pH, carbonate and calcium in the extracellular medium that 1. N. Vidavsky, S. Addadi, A. Schertel, D. Ben-Ezra, M. Shpigel, L. Addadi, we have obtained by developing in vivo approaches, and 2) the mechanisms S. Weiner, Calcium transport into the cells of the sea urchin larva in relation involved in transepithelial ion transport that we have characterized by to spicule formation. Proc. Natl. Acad. Sci. U.S.A, 113(45), 12637-12642, molecular and physiological approaches. Finally, I will show how changes 2016. 2. E. Beniash, J. Aizenberg, L. Addadi, S. Weiner, Amorphous in environmental parameters such as seawater pH influence biological calcium carbonate transforms into calcite during sea urchin larval spicule control and can provide information on coral biomineralization. growth. P. Roy. Soc. B-Biol. Sci., 264 (1380), 461-465, (1997). K 5 K 2 Towards bone-on-a-chip: cell differentiation and extracellular Biomineralization in echinoderms: developmental mechanisms matrix organization and evolution. Sana Ansari1,2,3, Esther Cramer1,2, Johanna Melke2,3, Keita Ito2,3, Sandra Charles Ettensohn*1 Hofmann2,3, Nico Somemrdijk1,3, Anat Akiva*1,3 1Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, 1Laboratory of Materials and Interface Chemistry and Center for Multiscale PA USA Electron Microscopy, Department of Chemical Engineering and Chemistry. Eindhoven University of Technology, Eindhoven, The Netherlands. All adult echinoderms have a calcite-based endoskeleton. Embryonic and 2Institute for Complex Molecular Systems. Eindhoven University of larval patterns of skeletogenesis, however, vary greatly across the phylum, Technology, Eindhoven, The Netherlands. revealing a rich history of evolutionary modifications to the developmental 3Department of Biomedical Engineering. Eindhoven University of programs that underlie biomineral formation in this group. The formation of Technology, Eindhoven, The Netherlands. the skeleton has been particularly well studied in embryos of euechinoid sea urchins, which have served as a major experimental model for developmental Introduction biologists for more than a century. The cellular behaviors that underlie The formation of bone involves a cascade of biological and chemical events skeleton formation in sea urchin embryos have been described in detail and that control the process of collagen mineralization in bone. In this process, many gene products that play essential roles in biomineral formation have bone cells named osteoblasts form a 3D organized collagen matrix and been identified. In addition, a complex transcriptional network that underlies secrete several non-collagenous proteins (NCPs) that control the skeletogenesis has recently been elucidated. This gene regulatory network mineralization process. However, the precise mechanism by which these links the early specification of embryonic skeletogenic cells (primary NCPs control the mineralization of collagen fibrils is not yet clear. In an mesenchyme cells, or PMCs) to their cellular behaviors and biomineral- attempt to get a direct observation on the time and place of the expression of forming properties. The PMC gene network is proving to be a powerful tool these proteins, and to study their role in collagen mineralization, we use an for understanding the genetic and molecular control of skeletogenesis in advanced in vitro model system. echinoderms and the evolution of biomineralization. Materials and methods. Here, human mesenchymal stromal cells (hMSCs) are seeded on 3D silk scaffold and are exposed to osteogenic medium and to continuous mechanical stimulation. Depending on the composition of the osteogenic medium and the specific mechanical load, we can control the differentiation of the hMSCs to osteoblasts and sequentially into osteocytes – the last