Polarising region cells express Cyclin D2 and Shh at HH21/22 (a, c) and at HH25/26 (b, d); but not p21cip1 and p57kip2 (e-h). Polarising region cells express p27kip1 at HH21/22 (i) and HH25/26 (j). p27kip1 is also expressed in the leg (L) polarising region at HH22, as well as in the wing (W) (k), and in differentiating myogenic cells in the wing at HH27/28 (l). p27kip1 protein is present in the polarising region at HH24 (m, n = 3/3). Note, gene expression patterns were observed in all embryos analysed (n => 12). Scale bars: a, c, e, g, i, l – 150 μm; b, d, f, h, j – 300 μm; k – 250 μm; - m – 75 μm.