Figure 1.

Embryonic tendons possess an organized actin cytoskeleton network, as well as cadherin-11 and N-cadherin cell-cell junctions. (a) The high cell density and an organized actin cytoskeleton network are visible in the midsubstance of E11 chick calcaneal tendons. Actin filaments (green) in embryonic tendon appear to form a continuous network between adjacent cells. (b) Cadherin-11 (red) and (c) N-cadherin (red) are present in E13 chick metatarsal tendons, but N-cadherin is localized to the exterior of the midsubstance of the tendon, while cadherin-11 appears in the interior of the midsubstance. Cell nuclei are labeled with blue. Figure 1A used with publisher’s permission from Schiele et al. 2015.¹³ Scale bar = 10 μm. Figure 1B and 1C adapted with publisher’s permission from Richardson et al. 2007.³⁷