title: Notch signaling-mediated cell-to-cell interaction is dependent on E-cadherin adhesion in adult rat anterior pituitary.
abstract: The rat anterior pituitary is composed of hormone-producing cells, non-hormone-producing cells (referred to as folliculostellate cells) and marginal layer cells. In the adult rat, progenitor cells of hormone-producing cells have recently been reported to be maintained within this non-hormone-producing cell population. In tissue, non-hormone-producing cells construct homophilic cell aggregates by the differential expression of the cell adhesion molecule E-cadherin. We have previously shown that Notch signaling, a known regulator of progenitor cells in a number of organs, is activated in the cell aggregates. We now investigate the relationship between Notch signaling and E-cadherin-mediated cell adhesion in the pituitary gland. Immunohistochemically, Notch signaling receptor Notch2 and the ligand Jagged1 were localized within E-cadherin-positive cells in the marginal cell layer and in the main part of the anterior lobe, whereas Notch1 was localized in E-cadherin-positive and -negative cells. Activation of Notch signaling within E-cadherin-positive cells was confirmed by immunostaining of the Notch target HES1. Notch2 and Jagged1 were always co-localized within the same cells suggesting that homologous cells have reciprocal effects in activating Notch signaling. When the E-cadherin function was inhibited by exposure to a monoclonal antibody (DECMA-1) in primary monolayer cell culture, the percentage of HES1-positive cells among Notch2-positive cells was less than half that of the control. The present results suggest that E-cadherin-mediated cell attachment is necessary for the activation of Notch signaling in the anterior pituitary gland but not for the expression of the Notch2 molecule.
authors.affiliation: Division of Histology and Cell Biology, Department of Anatomy, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Khongorzul
authors.initials: K
authors.lastname: Batchuluun
authors.affiliation: Division of Histology and Cell Biology, Department of Anatomy, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Morio
authors.initials: M
authors.lastname: Azuma
authors.affiliation: Division of Histology and Cell Biology, Department of Anatomy, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yashiro
authors.affiliation: Division of Histology and Cell Biology, Department of Anatomy, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan. kikuchim@jichi.ac.jp.|Laboratory of Natural History, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan. kikuchim@jichi.ac.jp.
authors.forename: Motoshi
authors.initials: M
authors.lastname: Kikuchi
mesh_terms: D000818:Animals; D015820:Cadherins / Q000378:metabolism*; D002448:Cell Adhesion; D002450:Cell Communication; D000072100:Jagged-1 Protein / Q000378:metabolism; D008024:Ligands; D008297:Male; D010903:Pituitary Gland, Anterior / Q000166:cytology* / Q000378:metabolism*; D017208:Rats, Wistar; D051880:Receptors, Notch / Q000378:metabolism*; D015398:Signal Transduction; D000072056:Transcription Factor HES-1 / Q000378:metabolism
chemical_list: C000610228:CDH1 protein, rat; D015820:Cadherins; C489735:Hes1 protein, rat; D000072100:Jagged-1 Protein; D008024:Ligands; D051880:Receptors, Notch; D000072056:Transcription Factor HES-1
keywords: E-cadherin; Folliculostellate cell; Notch signaling; Pituitary gland; Rat