Extended Data Fig. 5: Anatomical distribution of mechanosensitive end organs in hindlimb.

a, Summary of the distribution of the three main mechanosensitive end-organs in the mouse hindlimb. Data of Merkel cell and Meissner corpuscle distribution in the paw area was interpreted from the literature²³. There was no quantitative data for the distribution of the Merkel cells and Meissner corpuscles beyond the hindpaw. b, Top, a Pacinian corpuscle from a wild-type mouse under the confocal imaging after dissection ex vivo. The denser autofluorescence signals from the inner core cells and the onion-like layers of outer core cells could be visualised with high laser power and gain of the photon detector. Bottom, the inner core cells of a single Pacinian corpuscle were visualised using a double-transgenic strategy (ETV1-Cre x tdTomato) under in situ two-photon imaging at the hindlimb. c, Example plantar field of view of the toe with removed skin, where two tdTomato-positive Pacinian corpuscles are found close to the phalange. d, Six example hindlimbs with skin and muscle removed to expose the distal tibiofibular joint, and they consistently showed many tdTomato-positive Pacinian corpuscles (each bright spot is ETV1+ cells in the inner core area of one Pacinian corpuscle) wrapping around the fibula bone. e, Seven example confocal fields of view show that Troma1+ Merkel cells (arrowhead) and S100+ Meissner corpuscles (arrow) can be found in the foot. S100+ lanceolate endings are frequently spotted around the hair follicles of the hindlimb (bottom right). However, there was no Troma1+ signal observed in the hairy skin of the hindlimb across all 37 pieces of longitudinal skin samples from toe to thigh. f, Six example cross sections of hair follicles in the hindlimb stained using hematoxylin and eosin. There is no cytokeratin 20+ signal observed in the hairy skin of the hindlimb from ankle to thigh.