The Cellular Basis of Mechanosensory Merkel-Cell Innervation During Development
February 2019
in “
eLife
”
TLDR BMP signaling is essential for the development of touch domes.
The study investigated the development of mechanosensory Merkel cell-neurite complexes in mouse touch domes. At embryonic stage 16.5, touch domes formed as clusters of Merkel cells, keratinocytes, and Bmp4-expressing dermal cells. Overexpression of Noggin at E14.5 disrupted touch-dome formation but did not affect hair-follicle specification, indicating a specific requirement for BMP signaling in touch-dome development. Two neuronal populations initially targeted touch domes, but only one persisted in mature domes. Keratin-17-expressing keratinocytes, not Merkel cells, were essential for establishing innervation patterns. The study identified critical cell types and signaling pathways for Merkel-cell afferent targeting in mechanosensory compartments.