is expressed independently of RA signalling in the interdigital tissue of the mouse. In the wildtype (WT) E14.5 mouse, Rarβ and Meis2 expression can be seen in the intra-digit junction (A) and tissue surrounding the digits (B) of the HL, respectively. RA signalling is absent in the mouse Rdh10
trex/trex mutant as evidenced by the lack of Rarβ expression in the retained interdigital webbing of the HL (C). Meis2 is still expressed in this region (D), indicating that its expression is not dependent on RA signalling. Dorsal views of autopods are shown. Scale bar represent 500 μm.