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.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s00441-014-2054-y | DOI Listing |
Reproduction
December 2024
Department of Molecular and Integrative Physiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA.
In Brief: Endocrine-disrupting chemicals can impact reproduction by affecting the hypothalamic-pituitary-gonadal axis. This review emphasizes the impact of endocrine-disrupting chemicals on pituitary development and function.
Abstract: The pituitary gland is crucial for regulating many physiological systems, including reproduction.
J Reprod Dev
October 2024
Laboratory of Anatomy and Cell Biology, Department of Health Sciences, Kyorin University, Tokyo 181-8612, Japan.
The adenohypophysis is composed of the anterior and intermediate lobes (AL and IL, respectively), and secretes hormones that play an important role in reproduction. CD9- and SOX2-double (CD9/SOX2) positive cells located in the marginal cell layer (MCL) facing the Rathke's cleft in the AL and IL form the primary stem cell niche in the adult adenohypophysis of rats. In this study, we successfully obtained 3-dimensional (3D) cell aggregates that closely resembled the primary niche of MCL in vivo.
View Article and Find Full Text PDFEndocr J
June 2024
Institute for Endocrinology, Meiji University, Kanagawa 214-8571, Japan.
The pituitary gland is endocrine tissue composed of two distinct parts with different origins: the adenohypophysis (adenohypophyseal placode origin) and the neurohypophysis (neuroectoderm origin). Differentiation of endocrine cells in the pituitary gland leads to hormone synthesis, secretion into the capillary network, and transportation to target organs. In 1988, the discovery of the pituitary transcription factor PIT1 sparked research on endocrine cell differentiation.
View Article and Find Full Text PDFJ Reprod Dev
December 2023
Laboratory of Anatomy and Cell Biology, Department of Health Sciences, Kyorin University, Tokyo 181-8612, Japan.
The adenohypophysis is comprised of the anterior and intermediate lobes (AL and IL, respectively). Cluster of differentiation 9 (CD9)- and sex-determining region Y-box 2 (SOX2)-positive cells are stem/progenitor hormone-producing cells in the AL. They are located in the marginal cell layer (MCL) facing Rathke's cleft between the AL and IL (primary niche) and the parenchyma of the AL (secondary niche).
View Article and Find Full Text PDFCell Tissue Res
December 2023
Institute for Endocrinology, Meiji University, 1-1-1 Higashi-Mita, Tama-Ku, Kawasaki, Kanagawa, 214-8571, Japan.
The pituitary gland is a major endocrine tissue composing of two distinct entities, the adenohypophysis (anterior pituitary, cranial placode origin) and the neurohypophysis (posterior pituitary, neural ectoderm origin), and plays important roles in maintaining vital homeostasis. This tissue is maintained by a slow, consistent cell-renewal system of adult stem/progenitor cells. Recent accumulating evidence shows that neural crest-, head mesenchyme-, and endoderm lineage cells invade during pituitary development and contribute to the maintenance of the adult pituitary gland.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!