title: Tumour suppressor menin is essential for development of the pancreatic endocrine cells.
abstract: Mutations of the multiple endocrine neoplasia type 1 (MEN1) gene predispose patients to MEN1 that affects mainly endocrine tissues, suggesting important physiological functions of the gene in adult endocrine cells. Homozygous disruption of Men1 in mice causes embryonic lethality, whereas the eventual involvement of the gene in embryonic development of the endocrine cells remains unknown. Here, we show that homozygous Men1 knockout mice demonstrate a reduced number of glucagon-positive cells in the E12.5 pancreatic bud associated with apoptosis, whereas the exocrine pancreas development in these mice is not affected. Our data suggest that menin is involved in the survival of the early pancreatic endocrine cells during the first developmental transition. Furthermore, chimerism assay revealed that menin has an autonomous and specific effect on the development of islet cells. In addition, using pancreatic bud culture mimicking the differentiation of alpha- and beta-cells during the second transition, we show that loss of menin leads to the failure of endocrine cell development, altered pancreatic structure and a markedly decreased number of cells expressing neurogenin 3, indicating that menin is also required at this stage of the endocrine pancreas development. Taken together, our results suggest that menin plays an indispensable role in the development of the pancreatic endocrine cells.
authors.affiliation: CNRS UMR2501, Laboratoire Génétique Moléculaire, Signalisation et Cancer, Université Claude Bernard Lyon, Lyon F-69008, France.
authors.forename: Sandra
authors.initials: S
authors.lastname: Fontanière
authors.forename: Bertrand
authors.initials: B
authors.lastname: Duvillié
authors.forename: Raphaël
authors.initials: R
authors.lastname: Scharfmann
authors.forename: Christine
authors.initials: C
authors.lastname: Carreira
authors.forename: Zhao-Qi
authors.initials: ZQ
authors.lastname: Wang
authors.forename: Chang-Xian
authors.initials: CX
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D055098:Endocrine Cells / Q000166:cytology* / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D020287:In Situ Nick-End Labeling; D066298:In Vitro Techniques; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010179:Pancreas / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D009419:Nerve Tissue Proteins; D011518:Proto-Oncogene Proteins; C484898:Men1 protein, mouse; C407737:Neurog3 protein, mouse