Homotypic cell competition regulates proliferation and tiling of zebrafish pigment cells during colour pattern formation.
The adult striped pattern of zebrafish is composed of melanophores, iridophores and xanthophores arranged in superimposed layers in the skin. Previous studies have revealed that the assembly of pigment cells into stripes involves heterotypic interactions between all three chromatophore types. Here we investigate the role of homotypic interactions between cells of the same chromatophore type. Introduction of labelled progenitors into mutants lacking the corresponding cell type allowed us to define the impact of competitive interactions via long-term in vivo imaging. In the absence of endogenous cells, transplanted iridophores and xanthophores show an increased rate of proliferation and spread as a coherent net into vacant space. By contrast, melanophores have a limited capacity to spread in the skin even in the absence of competing endogenous cells. Our study reveals a key role for homotypic competitive interactions in determining number, direction of migration and individual spacing of cells within chromatophore populations.
Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany.
Brigitte
B
Walderich
Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany.
Ajeet Pratap
AP
Singh
Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany.
Prateek
P
Mahalwar
Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany.
Christiane
C
Nüsslein-Volhard
D000818:Animals; D001757:Blastomeres / Q000166:cytology / Q000378:metabolism; D019521:Body Patterning; D002450:Cell Communication; D049109:Cell Proliferation; D002856:Chromatophores / Q000166:cytology* / Q000378:metabolism; D003116:Color; D008547:Melanophores / Q000166:cytology / Q000378:metabolism; D018613:Microscopy, Confocal; D012867:Skin / Q000166:cytology / Q000196:embryology / Q000254:growth & development; D012880:Skin Pigmentation; D015027:Zebrafish