Symmetry breaking in the embryonic skin triggers directional and sequential plumage patterning

PLoS Biol. 2019 Oct 2;17(10):e3000448. doi: 10.1371/journal.pbio.3000448. eCollection 2019 Oct.

Abstract

The development of an organism involves the formation of patterns from initially homogeneous surfaces in a reproducible manner. Simulations of various theoretical models recapitulate final states of natural patterns, yet drawing testable hypotheses from those often remains difficult. Consequently, little is known about pattern-forming events. Here, we surveyed plumage patterns and their emergence in Galliformes, ratites, passerines, and penguins, together representing the three major taxa of the avian phylogeny, and built a unified model that not only reproduces final patterns but also intrinsically generates shared and varying directionality, sequence, and duration of patterning. We used in vivo and ex vivo experiments to test its parameter-based predictions. We showed that directional and sequential pattern progression depends on a species-specific prepattern: an initial break in surface symmetry launches a travelling front of sharply defined, oriented domains with self-organising capacity. This front propagates through the timely transfer of increased cell density mediated by cell proliferation, which controls overall patterning duration. These results show that universal mechanisms combining prepatterning and self-organisation govern the timely emergence of the plumage pattern in birds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Color
  • Embryo, Nonmammalian
  • Feathers / cytology
  • Feathers / growth & development
  • Feathers / metabolism
  • Galliformes / anatomy & histology
  • Galliformes / classification
  • Galliformes / genetics*
  • Galliformes / growth & development
  • Inheritance Patterns
  • Models, Statistical*
  • Morphogenesis / genetics
  • Palaeognathae / anatomy & histology
  • Palaeognathae / classification
  • Palaeognathae / genetics*
  • Palaeognathae / growth & development
  • Passeriformes / anatomy & histology
  • Passeriformes / classification
  • Passeriformes / genetics*
  • Passeriformes / growth & development
  • Phylogeny
  • Pigmentation / genetics*
  • Skin / cytology
  • Skin / growth & development
  • Skin / metabolism
  • Spheniscidae / anatomy & histology
  • Spheniscidae / classification
  • Spheniscidae / genetics*
  • Spheniscidae / growth & development

Grants and funding

This work was funded by a European Research Council Starting Grant #639060 to MM (https://erc.europa.eu/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.