Figure 4.

(A-AV) Comparisons of in situ hybridization data for four JcP markers at Q28/HH28 in horizontal cryostat sections at four section levels (in each case a single specimen). The markers are identified at the bottom left corner of each panel. Each row of panels [e.g., (A–F)] shows from left to right four section levels (dorsal to ventral sequence) reacted for a particular marker, followed by two pseudocolored images comparing the same marker, but paired with another at the two ventral-most levels studied. The first four rows show different markers in the quail, and the last four rows contain comparable material for the chick, so that panels taken long the vertical columns represent essentially the same section level and are comparable across the species. Green arrowheads in (C,AA) mark cells expressing a PcP marker that are found inside the differentially specified JcP domain. Asterisks in (I,J,O,P,U,V,AG,AH,AM,AN,AS,AT) identify the developing lateral spiriform nucleus. Numbers between brackets: code of the specimen in our collection. Scale bar = 300 μm.