RFX6 is needed for the development and maintenance of the β-cell phenotype
ABSTRACT RFX6 has recently been found to be essential for the development of the endocrine pancreas through studies in both humans and mice. Interestingly, this gene maintains a specific expression in the postnatal hormone producing cells of the pancreas. Moreover in humans, different types of diabetes mellitus affect obligate carriers of RFX6 mutations. Therefore, RFX6 appears to have a pivotal role in the maintenance of the phenotype of the β-cells in addition to their development. Extensive research is needed to specify this role and explore its significance in the efforts to treat diabetes with medications, or more importantly, through β-cell replacement.
Full-textDOI: · Available from: Constantin Polychronakos, Dec 23, 2013
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ABSTRACT: Developing cell-based diabetes therapies requires examining transcriptional mechanisms underlying human β cell development. However, increased knowledge is hampered by low availability of fetal pancreatic tissue and gene targeting strategies. Rodent models have elucidated transcription factor roles during islet organogenesis and maturation, but differences between mouse and human islets have been identified. The past 5 years have seen strides toward generating human β cell lines, the examination of human transcription factor expression, and studies utilizing induced pluripotent stem cells (iPS cells) and human embryonic stem (hES) cells to generate β-like cells. Nevertheless, much remains to be resolved. We present current knowledge of developing human β cell transcription factor expression, as compared to rodents. We also discuss recent studies employing transcription factor or epigenetic modulation to generate β cells.Trends in Endocrinology and Metabolism 05/2014; 25(8). DOI:10.1016/j.tem.2014.03.013 · 8.87 Impact Factor
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ABSTRACT: Insulin plays an extensively characterized role in the control of sugar metabolism, growth and homeostasis in a wide range of organisms. In vertebrate chordates, insulin is mainly produced by the beta cells of the endocrine pancreas, while in non-chordate animals insulin-producing cells are mainly found in the nervous system and/or scattered along the digestive tract. However, recent studies have indicated the notochord, the defining feature of the chordate phylum, as an additional site of expression of insulin-like peptides. Here we show that two of the three insulin-like genes identified in Ciona intestinalis, an invertebrate chordate with a dual life cycle, are first expressed in the developing notochord during embryogenesis and transition to distinct areas of the adult digestive tract after metamorphosis. In addition, we present data suggesting that the transcription factor Ciona Brachyury is involved in the control of notochord expression of at least one of these genes, Ciona insulin-like 2. Lastly, we review the information currently available on insulin-producing cells in ascidians and on pancreas-related transcription factors that might control their expression. genesis 00:00–00, 2014. © 2014 Wiley Periodicals, Inc.genesis 11/2014; 53(1). DOI:10.1002/dvg.22832 · 2.04 Impact Factor