title: Notch1-STAT3-ETBR signaling axis controls reactive astrocyte proliferation after brain injury.
abstract: Defining the signaling network that controls reactive astrogliosis may provide novel treatment targets for patients with diverse CNS injuries and pathologies. We report that the radial glial cell antigen RC2 identifies the majority of proliferating glial fibrillary acidic protein-positive (GFAP(+)) reactive astrocytes after stroke. These cells highly expressed endothelin receptor type B (ETB(R)) and Jagged1, a Notch1 receptor ligand. To study signaling in adult reactive astrocytes, we developed a model based on reactive astrocyte-derived neural stem cells isolated from GFAP-CreER-Notch1 conditional knockout (cKO) mice. By loss- and gain-of-function studies and promoter activity assays, we found that Jagged1/Notch1 signaling increased ETB(R) expression indirectly by raising the level of phosphorylated signal transducer and activator of transcription 3 (STAT3), a previously unidentified EDNRB transcriptional activator. Similar to inducible transgenic GFAP-CreER-Notch1-cKO mice, GFAP-CreER-ETB(R)-cKO mice exhibited a defect in reactive astrocyte proliferation after cerebral ischemia. Our results indicate that the Notch1-STAT3-ETB(R) axis connects a signaling network that promotes reactive astrocyte proliferation after brain injury.
authors.affiliation: Department of Medicine, Stem Cell Core, University of Vermont, Colchester, VT 05446; Department of Neurological Sciences, University of Vermont, Burlington, VT 05401; Neuroscience Graduate Program, University of Vermont, Burlington, VT 05401.
authors.forename: Matthew D
authors.identifier: http://orcid.org/0000-0001-7703-9729
authors.initials: MD
authors.lastname: LeComte
authors.affiliation: Department of Medicine, Stem Cell Core, University of Vermont, Colchester, VT 05446;
authors.forename: Issei S
authors.initials: IS
authors.lastname: Shimada
authors.affiliation: Department of Medicine, Stem Cell Core, University of Vermont, Colchester, VT 05446; Department of Neurological Sciences, University of Vermont, Burlington, VT 05401; Neuroscience Graduate Program, University of Vermont, Burlington, VT 05401.
authors.forename: Casey
authors.initials: C
authors.lastname: Sherwin
authors.affiliation: Department of Medicine, Stem Cell Core, University of Vermont, Colchester, VT 05446; Department of Neurological Sciences, University of Vermont, Burlington, VT 05401; Neuroscience Graduate Program, University of Vermont, Burlington, VT 05401 jeffrey.spees@uvm.edu.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Spees
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology*; D001930:Brain Injuries / Q000378:metabolism / Q000473:pathology*; D049109:Cell Proliferation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011401:Promoter Regions, Genetic; D044023:Receptor, Endothelin B / Q000235:genetics / Q000378:metabolism*; D051881:Receptor, Notch1 / Q000378:metabolism*; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: C497762:Notch1 protein, mouse; D044023:Receptor, Endothelin B; D051881:Receptor, Notch1; D050796:STAT3 Transcription Factor; C494087:Stat3 protein, mouse
keywords: ETBR; Notch1; STAT3; proliferation; reactive astrocyte