Fig. 5: Hypothalamic prosomere boundaries cannot be identified in chicken.
From: Resolving forebrain developmental organisation by analysis of differential growth patterns
A Mouse prosomeres (2012 model, schematic adapted from5) and major forebrain regions. B Prosomere boundaries (lines) and axes (arrows) in the hypothalamus and diencephalon. C Prosomere hypothalamic regions. D Ventral hypothalamic prosomere regions and identifying marker genes. E-G HCR-stained E13 mouse forebrains, selected prosomere boundaries overlaid. Dotted rectangle - area shown in F. Yellow arrow (F) = end of Shh+ve floor plate. White line (G) = extent of Pitx2+ve floor plate. H-K HCR-stained HH20 chicken forebrains, putative prosomere boundaries overlaid. Transverse hp1-2 boundary estimated using SIM1, NKX2-1 (M markers), FOXA1, SHH (RM markers). Longitudinal boundary estimated using OTP (PRM/PM marker), PITX2, FOXA1 (RM markers). L Described and observed prosomere boundary relations, HH20 chicken. M-O E7 chicken HCRs. Dotted rectangles—areas in M (right, different sample) and O (middle). Dotted lines—transverse (cyan) and longitudinal (magenta) boundaries as labelled. Transverse boundaries estimated using PITX2 (M/RM ventral midline marker), SIM1, FOXB1 (M markers, but see text for discussion), SIM1, OTP (Paraventricular (Pa) markers). White line—ventral midline PITX2. Arrows—forebrain axes inferred from boundary positions. P HCR-stained E13 mouse forebrain with selected transverse (cyan, p3-hp1) and longitudinal (magenta) prosomere boundaries. Hp1-hp2 boundary cannot be located based on PPa and TPa markers. Q UMAP plots of E11-14 mouse scRNA-Seq dataset39 showing cell cycle phase (left) and selected genes. Blue circle = neural progenitor cells (NPCs), blue triangle = paraventricular and supraoptic nucleus neurons (PVN/SON). Scale bars − 250 μm. (n = minimum of 3 for each HCR probe per species/stage). PPa peduncular Paraventricular, TPa terminal Paraventricular, ZLI zona limitans intrathalamica; for other abbreviations see (D).
