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Threshold dependent BMP Signaling: A Conserved Mechanism for Patterning the Ectoderm. Ethan Bier. Section of Cell and Developmental Biology, UCSD. dpp. dpp. “sog”. sog. snail. Epi. Neuro. Neuro. Dorsal. Meso. Epidermal Genes. Neuronal Genes. B. r. k. Neuronal Genes.
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Threshold dependent BMP Signaling: A Conserved Mechanism for Patterning the Ectoderm Ethan Bier Section of Cell and Developmental Biology, UCSD
dpp dpp “sog” sog snail Epi Neuro Neuro Dorsal Meso
Epidermal Genes Neuronal Genes B r k Neuronal Genes Mesodermal Genes = M e s o d e r m = N e u r o e c t o d e r m = N o n - N e u r a l E c t o d e r m Sog blocks BMP invasion of the neuroectoderm BMP Sog Dorsal
Neuronal Genes Epidermal Genes Neuronal Genes B r k Sog Mesodermal Genes = M e s o d e r m = N e u r o e c t o d e r m = N o n - N e u r a l E c t o d e r m Neural Genes are Repressed By BMP Signaling X Dpp
= M e s o d e r m = N e u r o e c t o d e r m = N o n - N e u r a l E c t o d e r m Neural Genes are Repressed By BMP Signaling Neuronal Genes Mesodermal Genes
dpp- Neural Genes are Repressed By BMP Signaling wt l’sc tkv
Neuronal Genes Neuronal Genes Mesodermal Genes = M e s o d e r m = N e u r o e c t o d e r m = N o n - N e u r a l E c t o d e r m Dpp Invades the Neuroectoderm of sog- Mutants Epidermal Genes Dpp X Sog
Neuronal Genes = M e s o d e r m = N e u r o e c t o d e r m = N o n - N e u r a l E c t o d e r m Dpp Invades the Neuroectoderm of sog- Mutants Epidermal Genes Dpp Mesodermal Genes
sog-; Dpdpp Dpp Invades the Neuroectoderm of sog- Mutants wt
Non-neural genes Dpp Neural genes B r k Sog Subdivision of the neuroectoderm Dorsal
Non-neural genes Dpp Neural genes Msh Neuronal genes Ind Vnd Subdivision of the neuroectoderm Dorsal
Dpp dpp msh ind vnd Dorsal BMPs Msx Gsh Nkx2.2 Mouse Neural Tube Sonic Hh Patterning the neuroectoderm in flies and mice DrosophilaNeuroectoderm
Ventral dominance Ventral dominant repression D msh ind vnd V
2 “ind” st2-dpp Generating lateralized embryos ECT 3 NE 2 1 MES Mid-lateralized Embryos -> Uniform “ind” levels of Dorsal
dpp msh ind vnd Gene expression in lateralized embryos Mid-Lateralized Embryos Dorsal
sog- sog dpp pMAD Localized Dpp activity along the A/P axis sog+ sog dpp pMAD
merge dpp Subdivision of the neuroectoderm
ECT 3 Brk Dpp 2 NE 1 MES st2-brk st2-brk Gene expression borders shift in BMP- cells
VertebrateNeuroectoderm Dpp BMP4 msh Msx1/2 Sog Chd ind Gsh/Pax6 vnd Nkx2.2 Ventral Midline Ventral Midline = Floorplate Conserved Patterning of the Neuroectoderm? DrosophilaNeuroectoderm