Figure 1
(a and b) In situ hybridization illustrating reelin expression in the developing chick autopod at 6 i.d. (a), and 7.5 i.d. (b). Prior to INZ (a) labeling is intense in the interdigital and distal undifferentiated mesoderm. From i.d. 7, interdigital expression is progressively downregulated (b). (c and d) In situ hybridization of mouse autopods prior to (p.c. day 12.5; c) and at the onset of (p.c. day 13.5; d) INZ. Note the intense labeling in the interdigital mesoderm in (c), and a weaker labeling in (d). (e and f) Detailed views of the third interdigit of chick leg buds to show differences in the intensity of reelin expression at 6 i.d. (e) and 7,5 i.d. (f). (g) QPCR analysis of reelin expression in the interdigital tissue of 6 i.d., 7 i.d. and 8 i.d. embryos. Bars represent gene expression levels in arbitrary units where values are normalized to the expression in the 6 i.d. tissue. ***P<0.001. (h) Representative western blot illustrating differences in Reelin levels in 6d vs 7.5d interdigital tissues. (i) Detailed view of a section of the chick autopod at 6 i.d. showing positive Reelin immunolabeling in the distal undifferentiated mesoderm. (j and k) Low-magnification views of the third interdigit at 6 i.d. (j), and 7.5 i.d. (k) immunostained for Reelin. (j′ and k′) Surface plots quantifiying the distribution of Reelin immunolabeling in (j and k). z axes=counts of pixel intensity; x and y axes = pixel localization in the corresponding pictures (j and k). Red and green colors represent higher and lower values, respectively
