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Reconciling diverse mammalian pigmentation patterns with a fundamental mathematical model.

ABSTRACT: Bands of colour extending laterally from the dorsal to ventral trunk are a common feature of mouse chimeras. These stripes were originally taken as evidence of the directed dorsoventral migration of melanoblasts (the embryonic precursors of melanocytes) as they colonize the developing skin. Depigmented 'belly spots' in mice with mutations in the receptor tyrosine kinase Kit are thought to represent a failure of this colonization, either due to impaired migration or proliferation. Tracing of single melanoblast clones, however, has revealed a diffuse distribution with high levels of axial mixing--hard to reconcile with directed migration. Here we construct an agent-based stochastic model calibrated by experimental measurements to investigate the formation of diffuse clones, chimeric stripes and belly spots. Our observations indicate that melanoblast colonization likely proceeds through a process of undirected migration, proliferation and tissue expansion, and that reduced proliferation is the cause of the belly spots in Kit mutants.

SUBMITTER: Mort RL

PROVIDER: S-EPMC4729835 | biostudies-other | 2016 Jan

REPOSITORIES: biostudies-other

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Reconciling diverse mammalian pigmentation patterns with a fundamental mathematical model.

Mort Richard L RL Ross Robert J H RJH Hainey Kirsten J KJ Harrison Olivia J OJ Keighren Margaret A MA Landini Gabriel G Baker Ruth E RE Painter Kevin J KJ Jackson Ian J IJ Yates Christian A CA

Nature communications 20160106

Bands of colour extending laterally from the dorsal to ventral trunk are a common feature of mouse chimeras. These stripes were originally taken as evidence of the directed dorsoventral migration of melanoblasts (the embryonic precursors of melanocytes) as they colonize the developing skin. Depigmented 'belly spots' in mice with mutations in the receptor tyrosine kinase Kit are thought to represent a failure of this colonization, either due to impaired migration or proliferation. Tracing of sing ...[more]

PMID: 26732977

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Reconciling diverse mammalian pigmentation patterns with a fundamental mathematical model.

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Reconciling diverse mammalian pigmentation patterns with a fundamental mathematical model.

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