title: Characterization of TGF-beta1 type II receptor expression in cultured cortical astrocytes.
abstract: The transforming growth factor-betas (TGF-betas) comprise a family of pleiotropic members that signal through two types of serine/threonine kinase receptors, named TGFRI (TGF-beta type I receptor) and TGFRII (TGF-beta type II receptor). We previously demonstrated that cortical neurons increase the astrocyte maturation marker, glial fibrillary acidic protein (GFAP), and thus, astrocyte differentiation, by inducing TGF-beta1 secretion by astrocytes in vitro. Although TGF-beta receptor expression has been described in different brain regions and cell types, their localization is still a subject of discussion. In the present work, we analyzed TGFRII expression in cultured cortical astrocytes from embryonic and newborn animals by immunocytochemistry, Western blot, and reverse transcriptase-polymerase chain reaction (RT-PCR). We report for the first time expression of TGFRII in embryonic glia. TGFRII immunostaining was punctual and spread throughout the cellular membrane of embryonic and newborn astrocytes. Western blot and RT-PCR assays revealed similar levels of the receptor in astrocytes from different ages. Identification of TGFRII in embryonic astrocytes is novel and might point to the multipotent precursor cell, radial glia, as a potential target for TGFbeta1 during astrocyte development.
authors.affiliation: Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, 21949-590, Rio de Janeiro, RJ, Brazil.
authors.forename: Vivian De Oliveira
authors.initials: Vde O
authors.lastname: Sousa
authors.forename: Juliana Carvalho
authors.initials: JC
authors.lastname: Almeida
authors.forename: Cristiane Monteiro
authors.initials: CM
authors.lastname: Eller
authors.forename: Flávia Carvalho Alcantara
authors.initials: FC
authors.lastname: Gomes
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism*; D015153:Blotting, Western; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology* / Q000196:embryology / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger / Q000378:metabolism; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction
chemical_list: D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II