Fig. 6. Striped patterns of Pby1, Pby2, En and Hunchback protein during Schistocerca embryogenesis. (A-C) The horizontal axis represents time, as measured in percentage development, while the vertical axis represents the length of the embryo, as measured from the tip of the head lobes to the end of the abdomen. 9-26%: extension occurs throughout the embryo but is concentrated in the abdomen. 26-28%: overall length decreases, owing to morphological segmentation, which contracts the embryo in accordian-like fashion, despite the persistence of extension in the abdomen. >28%: overall length increases as the result of nondifferential growth throughout embryo. (A) The schematic shows the timing of appearance and position along the anteroposterior axis of En protein (red) and Pby2 protein (green) during 
9-31% of development. Estimates of the timing of appearance of Pby2 protein are based on pby2 mRNA. (B) Same schematic as A, but showing Pby1 protein (purple), coincident Pby1 and Pby2 protein (purple and green hatched), and En protein (red) stripes. Broken purple lines indicate relatively weak expression as detected with anti-Pby. Vertical black bars indicate when Pby1 becomes restricted to the neuroectoderm (see text). Note that stripes of En join Pby1 stripes prior to their restriction. Also note that T2, T3 and the abdominal Pby1 stripes originate from within broader stripes of a two-segment periodicity (see text and Fig. 6). The A11 Pby1 and Pby2 stripe, which does not appear until 35%, is not shown. Non-stripe domains of Pby1 and Pby2 have also been omitted. A,B are based on 23 embryos stained with anti-Pby and anti-En, which were used to measure embryo length and the position of stripes; tracings of four representative embryos are shown (the intercalary stripe, Ic, is shown through the tissue of the antennae in the 31% embryo). The distribution of Pby1 and Pby2 protein was estimated by comparing the Pby and En pattern with the distribution of pby1 and pby2 mRNA (Fig. 4). (C) Same schematic as B, with the estimated position of three ectodermal Hb expression domains (Patel et al., 2001). The early anterior band occupies parasegments 1-3 and thus extends from the Mn to T1 segments, while concurrent weaker expression extends throughout the head (brown, strong subdomain; yellow, weak subdomain). It is not known when the domain extending from A4 to A5 disappears, as the mesodermal expression obscures the domain at 22%. The posterior extent of the domain extending from A7 to A9 should also be regarded as provisional. Staging estimates are ±1%. Oc, ocular; T, telson.
