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Unipotent, Atoh1+ progenitors maintain the Merkel cell population in embryonic and adult mice.

ABSTRACT: Resident progenitor cells in mammalian skin generate new cells as a part of tissue homeostasis. We sought to identify the progenitors of Merkel cells, a unique skin cell type that plays critical roles in mechanosensation. We found that some Atoh1-expressing cells in the hairy skin and whisker follicles are mitotically active at embryonic and postnatal ages. Genetic fate-mapping revealed that these Atoh1-expressing cells give rise solely to Merkel cells. Furthermore, selective ablation of Atoh1(+) skin cells in adult mice led to a permanent reduction in Merkel cell numbers, demonstrating that other stem cell populations are incapable of producing Merkel cells. These data identify a novel, unipotent progenitor population in the skin that gives rise to Merkel cells both during development and adulthood.

SUBMITTER: Wright MC

PROVIDER: S-EPMC4315254 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Unipotent, Atoh1+ progenitors maintain the Merkel cell population in embryonic and adult mice.

Wright Margaret C MC Reed-Geaghan Erin G EG Bolock Alexa M AM Fujiyama Tomoyuki T Hoshino Mikio M Maricich Stephen M SM

The Journal of cell biology 20150126 3

Resident progenitor cells in mammalian skin generate new cells as a part of tissue homeostasis. We sought to identify the progenitors of Merkel cells, a unique skin cell type that plays critical roles in mechanosensation. We found that some Atoh1-expressing cells in the hairy skin and whisker follicles are mitotically active at embryonic and postnatal ages. Genetic fate-mapping revealed that these Atoh1-expressing cells give rise solely to Merkel cells. Furthermore, selective ablation of Atoh1(+ ...[more]

PMID: 25624394

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