Arx and Nkx2.2 compound deficiency redirects pancreatic alpha- and beta-cell differentiation to a somatostatin/ghrelin co-expressing cell lineage

BMC Developmental Biology

Palle Serup²  Ahmed Mansouri¹  Patrick Collombat³  Simon Kordowich⁴ 

[1] Department of Clinical Neurophysiology, University of Göttingen, Robert-Koch Strasse 40, D-37075 Göttingen, Germany;Department of Developmental Biology, Hagedorn Research Institute, Niels Steensensvej 6, DK-2820 Gentofte, Denmark;Université de Nice Sophia-Antipolis, FR-06108 Nice, France;Department of Molecular Cell Biology, Max-Planck Institute for Biophysical Chemistry, Am Fassberg, D-37077 Göttingen, Germany

关键词: Pax4;    Pax6;    ghrelin;    somatostatin;    Nkx2.2;    Arx;   

Others  :  1087462
DOI  :  10.1186/1471-213X-11-52

 received in 2011-05-06, accepted in 2011-08-31,  发布年份 2011

【 摘 要 】

Background

Nkx2.2 and Arx represent key transcription factors implicated in the specification of islet cell subtypes during pancreas development. Mice deficient for Arx do not develop any alpha-cells whereas beta- and delta-cells are found in considerably higher numbers. In Nkx2.2 mutant animals, alpha- and beta-cell development is severely impaired whereas a ghrelin-expressing cell population is found augmented.

Notably, Arx transcription is clearly enhanced in Nkx2.2-deficient pancreata. Hence in order to precise the functional link between both factors we performed a comparative analysis of Nkx2.2/Arx single- and double-mutants but also of Pax6-deficient animals.

Results

We show that most of the ghrelin⁺ cells emerging in pancreata of Nkx2.2- and Pax6-deficient mice, express the alpha-cell specifier Arx, but also additional beta-cell related genes. In Nkx2.2-deficient mice, Arx directly co-localizes with iAPP, PC1/3 and Pdx1 suggesting an Nkx2.2-dependent control of Arx in committed beta-cells. The combined loss of Nkx2.2 and Arx likewise results in the formation of a hyperplastic ghrelin⁺ cell population at the expense of mature alpha- and beta-cells. Surprisingly, such Nkx2.2^-/-Arx^- ghrelin⁺ cells also express the somatostatin hormone.

Conclusions

Our data indicate that Nkx2.2 acts by reinforcing the transcriptional networks initiated by Pax4 and Arx in early committed beta- and alpha-cell, respectively. Our analysis also suggests that one of the coupled functions of Nkx2.2 and Pax4 is to counteract Arx gene activity in early committed beta-cells.

【 授权许可】

   
2011 Kordowich et al; licensee BioMed Central Ltd.

【 图 表 】

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【 参考文献 】

• [1]Adrian TE, Bloom SR, Hermansen K, Iversen J: Pancreatic polypeptide, glucagon and insulin secretion from the isolated perfused canine pancreas. Diabetologia 1978, 14:413-7.
• [2]Heller RS, Jenny M, Collombat P, Mansouri A, Tomasetto C, Madsen OD, Mellitzer G, Gradwohl G, Serup P: Genetic determinants of pancreatic epsilon-cell development. Dev Biol 2005, 286:217-24.
• [3]Korbonits M, Goldstone AP, Gueorguiev M, Grossman AB: Ghrelin--a hormone with multiple functions. Front Neuroendocrinol 2004, 25:27-68.
• [4]Roncoroni L, Violi V, Montanari M, Muri M: Effect of somatostatin on exocrine pancreas evaluated on a total external pancreatic fistula of neoplastic origin. Am J Gastroenterol 1983, 78:425-8.
• [5]Wierup N, Svensson H, Mulder H, Sundler F: The ghrelin cell: a novel developmentally regulated islet cell in the human pancreas. Regul Pept 2002, 107:63-9.
• [6]Dezaki K, Sone H, Yada T: Ghrelin attenuates glucose-induced insulin release in an autocrine/paracrine manner in pancreatic islets. Diabetologia 2006, 49:304-305.
• [7]Dezaki K, Sone H, Yada T: Ghrelin is a physiological regulator of insulin release in pancreatic islets and glucose homeostasis. Pharmacology & Therapeutics 2008, 118:239-249.
• [8]Herrera PL, Huarte J, Sanvito F, Meda P, Orci L, Vassalli JD: Embryogenesis of the murine endocrine pancreas; early expression of pancreatic polypeptide gene. Development 1991, 113:1257-65.
• [9]Offield MF, Jetton TL, Labosky PA, Ray M, Stein RW, Magnuson MA, Hogan BL, Wright CV: PDX-1 is required for pancreatic outgrowth and differentiation of the rostral duodenum. Development 1996, 122:983-95.
• [10]Pictet RL, Clark WR, Williams RH, Rutter WJ: An ultrastructural analysis of the developing embryonic pancreas. Dev Biol 1972, 29:436-67.
• [11]Teitelman G, Guz Y, Ivkovic S, Ehrlich M: Islet injury induces neurotrophin expression in pancreatic cells and reactive gliosis of peri-islet Schwann cells. J Neurobiol 1998, 34:304-18.
• [12]Upchurch BH, Aponte GW, Leiter AB: Expression of peptide YY in all four islet cell types in the developing mouse pancreas suggests a common peptide YY-producing progenitor. Development 1994, 120:245-52.
• [13]Prado CL, Pugh-Bernard AE, Elghazi L, Sosa-Pineda B, Sussel L: Ghrelin cells replace insulin-producing beta cells in two mouse models of pancreas development. Proc Natl Acad Sci USA 2004, 101:2924-9.
• [14]Miller K, Kim A, Kilimnik G, Jo J, Moka U, Periwal V, Hara M: Islet formation during the neonatal development in mice. PLoS One 2009, 4:e7739.
• [15]Gu G, Brown JR, Melton DA: Direct lineage tracing reveals the ontogeny of pancreatic cell fates during mouse embryogenesis. Mech Dev 2003, 120:35-43.
• [16]Jonsson J, Carlsson L, Edlund T, Edlund H: Insulin-promoter-factor 1 is required for pancreas development in mice. Nature 1994, 371:606-9.
• [17]Serup P, Petersen HV, Pedersen EE, Edlund H, Leonard J, Petersen JS, Larsson LI, Madsen OD: The homeodomain protein IPF-1/STF-1 is expressed in a subset of islet cells and promotes rat insulin 1 gene expression dependent on an intact E1 helix-loop-helix factor binding site. Biochem J 1995, 310(Pt 3):997-1003.
• [18]Apelqvist A, Li H, Sommer L, Beatus P, Anderson DJ, Honjo T, Hrabe de Angelis M, Lendahl U, Edlund H: Notch signalling controls pancreatic cell differentiation. Nature 1999, 400:877-81.
• [19]Gradwohl G, Dierich A, LeMeur M, Guillemot F: neurogenin3 is required for the development of the four endocrine cell lineages of the pancreas. Proc Natl Acad Sci USA 2000, 97:1607-11.
• [20]Gu G, Dubauskaite J, Melton DA: Direct evidence for the pancreatic lineage: NGN3+ cells are islet progenitors and are distinct from duct progenitors. Development 2002, 129:2447-57.
• [21]Schwitzgebel VM, Scheel DW, Conners JR, Kalamaras J, Lee JE, Anderson DJ, Sussel L, Johnson JD, German MS: Expression of neurogenin3 reveals an islet cell precursor population in the pancreas. Development 2000, 127:3533-42.
• [22]Sussel L, Kalamaras J, Hartigan-O'Connor DJ, Meneses JJ, Pedersen RA, Rubenstein JL, German MS: Mice lacking the homeodomain transcription factor Nkx2.2 have diabetes due to arrested differentiation of pancreatic beta cells. Development 1998, 125:2213-21.
• [23]Sander M, Sussel L, Conners J, Scheel D, Kalamaras J, Cruz F Dela, Schwitzgebel V, Hayes-Jordan A, German M: Homeobox gene Nkx6.1 lies downstream of Nkx2.2 in the major pathway of beta-cell formation in the pancreas. Development 2000, 127:5533-40.
• [24]St-Onge L, Sosa-Pineda B, Chowdhury K, Mansouri A, Gruss P: Pax6 is required for differentiation of glucagon-producing alpha-cells in mouse pancreas. Nature 1997, 387:406-9.
• [25]Heller RS, Stoffers DA, Liu A, Schedl A, Crenshaw EB, Madsen OD, Serup P: The role of Brn4/Pou3f4 and Pax6 in forming the pancreatic glucagon cell identity. Dev Biol 2004, 268:123-34.
• [26]Sosa-Pineda B, Chowdhury K, Torres M, Oliver G, Gruss P: The Pax4 gene is essential for differentiation of insulin-producing beta cells in the mammalian pancreas. Nature 1997, 386:399-402.
• [27]Collombat P, Mansouri A, Hecksher-Sorensen J, Serup P, Krull J, Gradwohl G, Gruss P: Opposing actions of Arx and Pax4 in endocrine pancreas development. Genes Dev 2003, 17:2591-603.
• [28]Jorgensen MC, Ahnfelt-Ronne J, Hald J, Madsen OD, Serup P, Hecksher-Sorensen J: An illustrated review of early pancreas development in the mouse. Endocr Rev 2007, 28:685-705.
• [29]Doyle MJ, Loomis ZL, Sussel L: Nkx2.2-repressor activity is sufficient to specify alpha-cells and a small number of beta-cells in the pancreatic islet. Development 2007, 134:515-23.
• [30]Doyle MJ, Sussel L: Nkx2.2 regulates beta-cell function in the mature islet. Diabetes 2007, 56:1999-2007.
• [31]Schaffer AE, Freude KK, Nelson SB, Sander M: Nkx6 transcription factors and Ptf1a function as antagonistic lineage determinants in multipotent pancreatic progenitors. Dev Cell 2010, 18:1022-9.
• [32]Sander M, Neubuser A, Kalamaras J, Ee HC, Martin GR, German MS: Genetic analysis reveals that PAX6 is required for normal transcription of pancreatic hormone genes and islet development. Genes Dev 1997, 11:1662-73.
• [33]Wang Q, Elghazi L, Martin S, Martins I, Srinivasan RS, Geng X, Sleeman M, Collombat P, Houghton J, Sosa-Pineda B: Ghrelin is a novel target of Pax4 in endocrine progenitors of the pancreas and duodenum. Dev Dyn 2008, 237:51-61.
• [34]Greenwood AL, Li S, Jones K, Melton DA: Notch signaling reveals developmental plasticity of Pax4(+) pancreatic endocrine progenitors and shunts them to a duct fate. Mech Dev 2007, 124:97-107.
• [35]Collombat P, Xu X, Ravassard P, Sosa-Pineda B, Dussaud S, Billestrup N, Madsen OD, Serup P, Heimberg H, Mansouri A: The ectopic expression of Pax4 in the mouse pancreas converts progenitor cells into alpha and subsequently beta cells. Cell 2009, 138:449-62.
• [36]Collombat P, Hecksher-Sorensen J, Broccoli V, Krull J, Ponte I, Mundiger T, Smith J, Gruss P, Serup P, Mansouri A: The simultaneous loss of Arx and Pax4 genes promotes a somatostatin-producing cell fate specification at the expense of the alpha- and beta-cell lineages in the mouse endocrine pancreas. Development 2005, 132:2969-80.
• [37]Collombat P, Hecksher-Sorensen J, Krull J, Berger J, Riedel D, Herrera PL, Serup P, Mansouri A: Embryonic endocrine pancreas and mature beta cells acquire alpha and PP cell phenotypes upon Arx misexpression. J Clin Invest 2007, 117:961-70.
• [38]Chao CS, Loomis ZL, Lee JE, Sussel L: Genetic identification of a novel NeuroD1 function in the early differentiation of islet alpha, PP and epsilon cells. Dev Biol 2007, 312:523-32.
• [39]Wang J, Elghazi L, Parker SE, Kizilocak H, Asano M, Sussel L, Sosa-Pineda B: The concerted activities of Pax4 and Nkx2.2 are essential to initiate pancreatic beta-cell differentiation. Dev Biol 2004, 266:178-89.
• [40]Gosmain Y, Marthinet E, Cheyssac C, Guerardel A, Mamin A, Katz LS, Bouzakri K, Philippe J: Pax6 controls the expression of critical genes involved in pancreatic {alpha} cell differentiation and function. J Biol Chem 2010, 285:33381-93.
• [41]Katz LS, Gosmain Y, Marthinet E, Philippe J: Pax6 regulates the proglucagon processing enzyme PC2 and its chaperone 7B2. Mol Cell Biol 2009, 29:2322-34.
• [42]Nishimura W, Rowan S, Salameh T, Maas RL, Bonner-Weir S, Sell SM, Sharma A: Preferential reduction of beta cells derived from Pax6-MafB pathway in MafB deficient mice. Dev Biol 2008, 314:443-56.
• [43]Ahlgren U, Jonsson J, Edlund H: The morphogenesis of the pancreatic mesenchyme is uncoupled from that of the pancreatic epithelium in IPF1/PDX1-deficient mice. Development 1996, 122:1409-16.
• [44]Ohlsson H, Karlsson K, Edlund T: IPF1, a homeodomain-containing transactivator of the insulin gene. Embo J 1993, 12:4251-9.
• [45]Miller CP, McGehee RE Jr, Habener JF: IDX-1: a new homeodomain transcription factor expressed in rat pancreatic islets and duodenum that transactivates the somatostatin gene. Embo J 1994, 13:1145-56.
• [46]Lynn FC, Smith SB, Wilson ME, Yang KY, Nekrep N, German MS: Sox9 coordinates a transcriptional network in pancreatic progenitor cells. Proc Natl Acad Sci USA 2007, 104:10500-5.
• [47]Seymour PA, Freude KK, Tran MN, Mayes EE, Jensen J, Kist R, Scherer G, Sander M: SOX9 is required for maintenance of the pancreatic progenitor cell pool. Proc Natl Acad Sci USA 2007, 104:1865-70.
• [48]Hill JT, Chao CS, Anderson KR, Kaufman F, Johnson CW, Sussel L: Nkx2.2 activates the ghrelin promoter in pancreatic islet cells. Mol Endocrinol 2010, 24:381-90.
• [49]Andersen FG, Heller RS, Petersen HV, Jensen J, Madsen OD, Serup P: Pax6 and Cdx2/3 form a functional complex on the rat glucagon gene promoter G1-element. FEBS Lett 1999, 445:306-10.