Cluster of Excellence –
University of Freiburg

Dr. Sebastian Arnold

Dr. Sebastian Arnold

University Medical Centre Freiburg
Zentrale Klinische Forschung

+49 761 270 63120

During embryogenesis cells of the developing organism become progressively restricted in their developmental potential. Pluripotent cells of the epiblast get specified to different lineages according to their position within the embryo at certain critical time points to establish the various different cell types of the body. This initial lineage restriction also defines the primary body pattern, lays down the set of different cell types required for all following steps during development and is maintained throughout the entire lifespan. Lineage specification is influenced by dynamic cell-cell interactions and extracellular stimuli - e.g. growth-factors or extracellular components – to define the route of cells from stem- and progenitor cells to terminal differentiation.

Our group is mainly interested in the processes that shape the embryo during the time when pluripotent progenitor cells of the epiblast become specified to the three germ layers, namely ectoderm, mesoderm and endoderm. We aim to contribute to the understanding of this gastrulation process by using combinations of mouse genetics, embryo imaging techniques and in vitro cell culture systems. Enhancing current knowledge of early cell type specification events will be instrumental in developing new strategies to use stem- and progenitor cells, such as embryonic stem (ES) cells and induced pluripotent cells (iPCs) for novel approaches in regenerative medicine and tissue replacement.

10 selected publications

  • The T-box transcription factor Eomesodermin acts upstream of Mesp1 to specify cardiac mesoderm during mouse gastrulation.
    Costello I, Pimeisl IM, Dräger S, Bikoff EK, Robertson EJ, Arnold SJ (2011).
    Nat Cell Biol 13(9), 1084-91.
  • Pluripotency Factors Regulate Definitive Endoderm Specification through Eomesodermin.
    Teo AK, Arnold SJ, Trotter MWB, Brown S, Ang LT, Chng Z, Robertson EJ, Dunn NR, Vallier L (2011).
    Genes Dev 25, 238-250.
  • Inversin relays Frizzled-8 signals to promote proximal pronephros development.
    Lienkamp S, Ganner A, Boehlke C, Schmidt T, Arnold SJ, Schäfer T, Romaker D, Schuler J, Hoff S, Powelske C, Eifler A, Krönig C, Bullerkotte A, Nitschke R, Kuehn EW, Kim E, Burkhardt H, Brox T, Ronneberger O, Gloy J, Walz G (2010).
    PNAS 107(47), 20388-20393.
  • Generation and analysis of a mouse line harboring GFP in the Eomes/Tbr2 locus.
    Arnold SJ, Sugnaseelan J, Groszer M, Srinivas S, Robertson EJ (2009).
    Genesis 47 (11), 775-81.
  • Making a commitment: cell lineage allocation and axis patterning in the early mouse embryo.
    Arnold SJ, Robertson EJ (2009).
    Nat Rev Mol Cell Biol 10, 91-103.
  • The T-box transcription factor Eomes/Tbr2 regulates neurogenesis in the cortical subventricular zone.
    Arnold SJ, Huang GJ, Cheung AF, Era T, Nishikawa S, Bikoff EK, Molnar Z, Robertson EJ,  Groszer M (2008).
    Genes Dev 22, 2479-84.
  • Pivotal roles for eomesodermin during axis formation, epithelium-to-mesenchyme transition and endoderm specification in the mouse.
    Arnold SJ, Hofmann UK, Bikoff EK, Robertson EJ (2008).
    Development 135, 501-11
  • VACTERL/caudal regression/Currarino syndrome-like malformations in mice with mutation in the proprotein convertase Pcsk5.
    Szumska D, Pieles G, Essalmani R, Bilski M, Mesnard D, Kaur K, Franklyn A, El Omari K, Jefferis J, Bentham J, Taylor JM, Schneider JE, Arnold SJ, Johnson P et al (2008).
    Genes Dev 22, 1465-77
  • Blimp1 regulates development of the posterior forelimb, caudal pharyngeal arches, heart and sensory vibrissae in mice.
    Robertson EJ, Charatsi I, Joyner CJ, Koonce CH, Morgan M, Islam A, Paterson C, Lejsek E, Arnold SJ, Kallies A et al (2007).
    Development 134, 4335-45.
  • Dose-dependent Smad1, Smad5 and Smad8 signaling in the early mouse embryo.
    Arnold SJ, Maretto S, Islam A, Bikoff EK, Robertson EJ (2006).
    Dev Biol 296, 104-18