title: Beyond Turing: mechanochemical pattern formation in biological tissues.
abstract: During embryogenesis, chemical (morphogen) and mechanical patterns develop within tissues in a self-organized way. More than 60 years ago, Turing proposed his famous reaction-diffusion model for such processes, assuming chemical interactions as the main driving force in tissue patterning. However, experimental identification of corresponding molecular candidates is still incomplete. Recent results suggest that beside morphogens, also tissue mechanics play a significant role in these patterning processes.
  
  
  
  Combining continuous finite strain with discrete cellular tissue models, we present and numerically investigate mechanochemical processes, in which morphogen dynamics and tissue mechanics are coupled by feedback loops. We consider three different mechanical cues involved in such feedbacks: strain, stress, and compression. Based on experimental results, for each case, we present a feedback loop spontaneously creating robust mechanochemical patterns. In contrast to Turing-type models, simple mechanochemical interaction terms are sufficient to create de novo patterns.
  
  
  
  Our results emphasize mechanochemical processes as possible candidates controlling different steps of embryogenesis. To motivate further experimental research discovering related mechanisms in living tissues, we also present predictive in silicio experiments.
  
  
  
  Reviewer 1 - Marek Kimmel; Reviewer 2 - Konstantin Doubrovinski (nominated by Ned Wingreen); Reviewer 3 - Jun Allard (nominated by William Hlavacek).
authors.affiliation: Institute of Applied Mathematics, BioQuant and Interdisciplinary Center of Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany. mmercker_bioscience@gmx.de.
authors.forename: Moritz
authors.initials: M
authors.lastname: Mercker
authors.affiliation: Institute of Applied Mathematics, BioQuant and Interdisciplinary Center of Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany.|Department Mathematik, FAU Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Brinkmann
authors.affiliation: Institute of Applied Mathematics, BioQuant and Interdisciplinary Center of Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Marciniak-Czochra
authors.affiliation: Department Mathematik, FAU Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Richter
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D019521:Body Patterning; D004058:Diffusion; D025461:Feedback, Physiological; D008954:Models, Biological
keywords: Development; Long-range inhibition; Mechanochemistry; Mechanotransduction; Morphogens; Pattern formation; Reaction-diffusion; Tissue mechanics; Tissue morphogenesis