151. Paternal allelic mutation at the Kcnq1 locus reduces pancreatic β-cell mass by epigenetic modification of Cdkn1c
- Author
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Maki Koyanagi-Kimura, Ayumi Kanno, Yoshiaki Kido, Wataru Nishimura, Yuka Ihara, Kazuki Yasuda, Nobuya Inagaki, Kazuaki Nagashima, Shun-ichiro Asahara, Yukina Kawada, Yuki Shibutani, Hiroaki Etoh, Tomokazu Matsuda, Hiroshi Inoue, Alberto Bartolomé, Kyoko Teruyama, Tetsuya Hosooka, Yushi Hirota, Masato Kasuga, Michael J. Higgins, Susumu Seino, Michihiro Matsumoto, Naoko Hashimoto, and Hiroyuki Inoue
- Subjects
Male ,endocrine system diseases ,Immunoblotting ,Inheritance Patterns ,Gene Expression ,Locus (genetics) ,Biology ,Epigenesis, Genetic ,Genomic Imprinting ,Insulin-Secreting Cells ,Gene expression ,Insulin Secretion ,medicine ,Animals ,Insulin ,Epigenetics ,Allele ,Gene ,Cyclin-Dependent Kinase Inhibitor p57 ,Alleles ,Genetics ,Mice, Knockout ,Multidisciplinary ,KCNQ1OT1 ,urogenital system ,Reverse Transcriptase Polymerase Chain Reaction ,Pancreatic islets ,Biological Sciences ,Glucose Tolerance Test ,Molecular biology ,medicine.anatomical_structure ,Glucose ,KCNQ1 Potassium Channel ,Mutation ,Genomic imprinting - Abstract
Genetic factors are important determinants of the onset and progression of diabetes mellitus. Numerous susceptibility genes for type 2 diabetes, including potassium voltage-gated channel, KQT-like subfamily Q, member1 (KCNQ1), have been identified in humans by genome-wide analyses and other studies. Experiments with genetically modified mice have also implicated various genes in the pathogenesis of diabetes. However, the possible effects of the parent of origin for diabetes susceptibility alleles on disease onset have remained unclear. Here, we show that a mutation at the Kcnq1 locus reduces pancreatic β-cell mass in mice by epigenetic modulation only when it is inherited from the father. The noncoding RNA KCNQ1 overlapping transcript1 (Kcnq1ot1) is expressed from the Kcnq1 locus and regulates the expression of neighboring genes on the paternal allele. We found that disruption of Kcnq1 results in reduced Kcnq1ot1 expression as well as the increased expression of cyclin-dependent kinase inhibitor 1C (Cdkn1c), an imprinted gene that encodes a cell cycle inhibitor, only when the mutation is on the paternal allele. Furthermore, histone modification at the Cdkn1c promoter region in pancreatic islets was found to contribute to this phenomenon. Our observations suggest that the Kcnq1 genomic region directly regulates pancreatic β-cell mass and that genomic imprinting may be a determinant of the onset of diabetes mellitus.
- Published
- 2015