Dual transcriptional activities of PAX3 and PAX7 spatially encode spinal cell fates through distinct gene networks
Fig 1
BMP signaling-dependent dorso-to-ventral gradient of PAX3/7 transcriptional activity revealed by the P34::tk::LacZ reporter.
(A) DV expression patterns of neural progenitor (NP) and interneuron (IN) TF markers in the developing spinal cord. (B) Immunostaining for β-galactosidase (β-gal; red/grey), GFP (blue/grey) and either OLIG3 (green/grey) or pSMAD1/5/9 (green/grey) on transverse sections of E9.0 and E9.5 P34::tk::LacZ; Pax3+/GFP spinal cords at brachial level. Black and white panels show magnified views of the boxed region. (C) Quantification of the βgal, GFP and OLIG3 (i) or pSMAD1/5/9 (ii) signal intensity (in arbitrary units, AU) along the DV axis of the neural tube, expressed as the percentage of the neural tube length (bar plots: mean ± s.e.m). (D) Turquoise fluorescence (white) and immunostaining for GFP (blue) and βgal (white) on transverse sections of chick embryos 24 h post-electroporation (hpe) with the indicated constructs. Only the electroporated side of the neural tube is shown (E) Quantification of βgal or Turquoise signal intensity (AU) along the DV axis of the neural tube of chick embryos 24 hpe with the indicated constructs, expressed as a percentage of the neural tube length (mean ± s.e.m). (F) Immunostaining for β-gal (red/grey) and GFP (green) on transverse sections at the brachial level of E9.5 P34::tk::LacZ; Pax3+/GFP and Pax3GFP/GFP embryos. (G) Immunostaining for GFP (blue) and βgal (white) on transverse sections of chick embryos 24 hpe with the indicated constructs. Only the electroporated side of the neural tube is shown. In all images, white dotted lines outline neural tubes. Scale bars: 50 µm. The data underlying this figure can be found in S7 Table.