Project description:This SuperSeries is composed of the following subset Series:; GSE16691: Transcriptional regulation by Norrin-Frizzled4 signaling in the embryonic yolk sac; GSE16703: Long-term effect on the transcriptome of a decrement in Norrin/Frizzled4/Lrp signaling in retinal endothelial cells; GSE16705: Transcriptional response to Frizzled4 signaling in cultured retinal endothelial cells; GSE16707: Long-term effect on the transcriptome of loss of Frizzled4 signaling in cerebellar endothelial cells Experiment Overall Design: Refer to individual Series
Project description:Transcriptional profiles of the embryonic yolk sac from embryos with ectopic Norrin expression were compared to their wild type littermate controls. The goal is to identify the transcriptional response to Norrin-Frizzled 4 signaling during embryonic angiogenesis.
Project description:Transcriptional profiles of the embryonic yolk sac from embryos with ectopic Norrin expression were compared to their wild type littermate controls. The goal is to identify the transcriptional response to Norrin-Frizzled 4 signaling during embryonic angiogenesis. Experiment Overall Design: Ectopic Norrin expression was achieved using a conditional over-expression strategy. Yolk sacs from 3-5 embryos were pooled for each sample and 3 replicates of both control and experimental groups were analyzed.
Project description:Using mice with targeted gene mutations, we identify (1) distinct roles for different canonical Wnt signaling components in central nervous system (CNS) vascular development and in the specification of the blood-brain and blood-retina barriers (BBB and BRB) and (2) differential sensitivities of the vasculature in various CNS regions to perturbations in canonical Wnt signaling components. We find nearly equivalent roles for Lrp5 and Lrp6 in brain vascular development and barrier maintenance but a dominant role for Lrp5 in the retinal vasculature, an especially high sensitivity of the BBB in the cerebellum and pons/interpeduncular nuclei to decrements in canonical Wnt signaling, and plasticity in the barrier properties of mature CNS vasculature. Brain and retinal vascular defects caused by loss of Norrin/Frizzled4 signaling can be fully rescued by stabilizing beta-catenin, and loss of beta-catenin’s transcriptional activation domain or expression of a dominant negative Tcf4 recapitulates the vascular development and barrier defects seen with loss of receptor, co-receptor, or ligand, indicating that Norrin/Frizzled4 signaling acts predominantly by beta-catenin-dependent transcriptional regulation. This work strongly supports a model in which identical or nearly identical canonical Wnt signaling mechanisms mediate neural tube and retinal vascularization and maintain the BBB and BRB. Total retina RNA from P10 WT, NdpKO, Ctnnb1flex3/+;Pdgfb-CreER, and NdpKO;Ctnnb1flex3/+;Pdgfb-CreER mice was subjected to RNAseq
Project description:Using mice with targeted gene mutations, we identify (1) distinct roles for different canonical Wnt signaling components in central nervous system (CNS) vascular development and in the specification of the blood-brain and blood-retina barriers (BBB and BRB) and (2) differential sensitivities of the vasculature in various CNS regions to perturbations in canonical Wnt signaling components. We find nearly equivalent roles for Lrp5 and Lrp6 in brain vascular development and barrier maintenance but a dominant role for Lrp5 in the retinal vasculature, an especially high sensitivity of the BBB in the cerebellum and pons/interpeduncular nuclei to decrements in canonical Wnt signaling, and plasticity in the barrier properties of mature CNS vasculature. Brain and retinal vascular defects caused by loss of Norrin/Frizzled4 signaling can be fully rescued by stabilizing beta-catenin, and loss of beta-catenin’s transcriptional activation domain or expression of a dominant negative Tcf4 recapitulates the vascular development and barrier defects seen with loss of receptor, co-receptor, or ligand, indicating that Norrin/Frizzled4 signaling acts predominantly by beta-catenin-dependent transcriptional regulation. This work strongly supports a model in which identical or nearly identical canonical Wnt signaling mechanisms mediate neural tube and retinal vascularization and maintain the BBB and BRB.