Skip to main content
. 2023 May 11;299(6):104805. doi: 10.1016/j.jbc.2023.104805

Figure 2.

Figure 2

Undifferentiated Hes1-creER+cells surrounding the mesenchymal condensation provide skeletal progenitor cells.A–G, Cell-fate analysis of Hes1-creER+ mesenchymal cells of the condensation stage, pulsed at E10.5. Hes1-creER; R26RtdTomato femurs carrying CBF1:Venus (B and E) or Col1a1(2.3kb)-GFP (F and G) reporters. A, Limb bud at E11.5. Scale bar: 200 μm. n = 4 mice. B, Magnified view of mesenchymal condensation at E11.5. Scale bar: 20 μm. n = 4 mice. C and D, Immunostaining for MYH3 (C) and endomucin (EMCN) (D). Arrow: Hes1-creER+Emcn+ cells. Scale bar: 20 μm. n = 4 mice. E, Cartilage template at E13.5. Right panel: magnified view of Area (1). Dotted line: cartilage-perichondrium border. Grey: DIC. Scale bar: 200 μm (left), 50 μm (right). n = 4 mice. F, Cartilage-perichondrium immunostaining for SOX9, osterix (OSX), MYH3 and EMCN. Scale bar: 20 μm. n = 4 mice. G, Neonatal femur at P0, after 9 days of chase. Right panels: magnified views of (1: growth plate, 2: bone marrow). Scale bar: 200 μm (left), 20 μm (right 2 panels). n = 4 mice. H, Diagram of Hes1+ mesenchymal cell fates. Hes1+So x 9neg cells surrounding the condensation are bona fide skeletal progenitor cells during endochondral bone development, contributing to both chondrocytes and perichondrial cells and subsequently to all limb skeletal cells. MYH3, myosin heavy chain 3.