Numb Deletion in POMC-Expressing Cells Impairs Pituitary Intermediate Lobe Cell Adhesion, Progenitor Cell Localization, and Neuro-Intermediate Lobe Boundary Formation
| Autor: | Leah B. Goldberg, Lori T. Raetzman, Tyler B. Moran, Sarah L. Serviss |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
medicine.medical_specialty
Cell type Pituitary gland Pro-Opiomelanocortin Melanotrophs Notch signaling pathway Nerve Tissue Proteins Gonadotrophs Biology Article Adherens junction Mice Endocrinology Cell Movement Internal medicine Cell Adhesion medicine Animals Protein Isoforms Pituitary Gland Intermediate Progenitor cell Cell adhesion Molecular Biology Cell Proliferation Mice Knockout Integrases Receptors Notch Cadherin Stem Cells Intracellular Signaling Peptides and Proteins Gene Expression Regulation Developmental Membrane Proteins General Medicine Cell biology medicine.anatomical_structure NUMB Gene Deletion |
| Zdroj: | Molecular Endocrinology. 25:117-127 |
| ISSN: | 1944-9917 0888-8809 |
| DOI: | 10.1210/me.2010-0248 |
| Popis: | The pituitary gland contains six distinct hormone-secreting cell types that are essential for basic physiological processes including fertility and responding to stress. Formation of hormone-secreting cells during development relies on Notch signaling to prevent progenitors from prematurely differentiating. The nature of the signal curtailing Notch signaling in the pituitary is unknown, but a good candidate is the endocytic adaptor protein NUMB. NUMB targets Notch for proteolytic degradation, but it also has a broad range of actions, including stabilizing adherens junctions through interactions with cadherins and influencing cell proliferation by stabilizing expression of the tumor suppressor protein p53. Here, we show that NUMB and its closely related homolog, NUMBLIKE, are expressed in undifferentiated cells during development and later in gonadotropes in the anterior lobe and melanotropes of the intermediate lobe. All four isoforms of NUMB, are detectable in the pituitary, with the shorter forms becoming more prominent after adolescence. Conditionally deleting Numb and Numblike in the intermediate lobe melanotropes with Pomc Cre mice dramatically alters the morphology of cells in the intermediate lobe, coincident with impaired localization of adherens junctions proteins including E-CADHERIN, N-CADHERIN, β-CATENIN, and α-CATENIN. Strikingly, the border between posterior and intermediate lobes is also disrupted. These mice also have disorganized progenitor cells, marked by SOX2, but proliferation is unaffected. Unexpectedly, Notch activity appears normal in conditional knockout mice. Thus, Numb is critical for maintaining cell-cell interactions in the pituitary intermediate lobe that are essential for proper cell placement. |
| Databáze: | OpenAIRE |
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