title: Localization of juxtacrine factor ephrin-B2 in pituitary stem/progenitor cell niches throughout life.
abstract: We have recently reported that Sox2-expressing pituitary stem/progenitor cells contact each other via a tight-junction protein CAR to form stem/progenitor cell niches in the marginal cell layer facing the lumen and in the clusters scattered in the parenchyma of the anterior lobe. However, the microenvironment of the niche for the maintenance of stem cell function in the pituitary remains obscure. In this study of pituitary stem/progenitor cell niches, we have attempted to identify the expression of juxtacrine factor ephrin and its receptor. We have found that ephrin-B2 is expressed in the pituitary throughout development but changes its localization pattern. Notably, in the adult pituitary, ephrin-B2 immuno-signals occur in SOX2-, E-cadherin-, and CAR-triple-positive stem/progenitor cells in the niches. Our data suggest that ephrin-B2 signaling has an important role in the formation of pituitary stem/progenitor cell niches and in pituitary organogenesis.
authors.affiliation: Division of Life Science, Graduate School of Agriculture, Meiji University, Kanagawa, 214-8571, Japan.
authors.forename: Saishu
authors.initials: S
authors.lastname: Yoshida
authors.forename: Takako
authors.initials: T
authors.lastname: Kato
authors.forename: Masashi
authors.initials: M
authors.lastname: Higuchi
authors.forename: Mo
authors.initials: M
authors.lastname: Chen
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ueharu
authors.forename: Naoto
authors.initials: N
authors.lastname: Nishimura
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kato
mesh_terms: D000375:Aging / Q000378:metabolism; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D036388:Ephrin-B2 / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006728:Hormones / Q000378:metabolism; D008297:Male; D010902:Pituitary Gland / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D021381:Protein Transport; D051381:Rats; D064568:S100 Calcium Binding Protein beta Subunit / Q000235:genetics / Q000378:metabolism; D055748:SOXB1 Transcription Factors / Q000378:metabolism; D055153:Stem Cell Niche; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D015820:Cadherins; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein; D036388:Ephrin-B2; D018398:Homeodomain Proteins; D006728:Hormones; C102134:Prophet of Pit-1 protein; D064568:S100 Calcium Binding Protein beta Subunit; D055748:SOXB1 Transcription Factors; D049452:Green Fluorescent Proteins