| First Author | Sakurai Y | Year | 2024 |
| Journal | Diabetes | Volume | 73 |
| Issue | 3 | Pages | 474-489 |
| PubMed ID | 38064504 | Mgi Jnum | J:345911 |
| Mgi Id | MGI:7611774 | Doi | 10.2337/db23-0150 |
| Citation | Sakurai Y, et al. (2024) Overexpression of UBE2E2 in Mouse Pancreatic beta-Cells Leads to Glucose Intolerance via Reduction of beta-Cell Mass. Diabetes 73(3):474-489 |
| abstractText | Genome-wide association studies have identified several gene polymorphisms, including UBE2E2, associated with type 2 diabetes. Although UBE2E2 is one of the ubiquitin-conjugating enzymes involved in the process of ubiquitin modifications, the pathophysiological roles of UBE2E2 in metabolic dysfunction are not yet understood. Here, we showed upregulated UBE2E2 expression in the islets of a mouse model of diet-induced obesity. The diabetes risk allele of UBE2E2 (rs13094957) in noncoding regions was associated with upregulation of UBE2E2 mRNA in the human pancreas. Although glucose-stimulated insulin secretion was intact in the isolated islets, pancreatic beta-cell-specific UBE2E2-transgenic (TG) mice exhibited reduced insulin secretion and decreased beta-cell mass. In TG mice, suppressed proliferation of beta-cells before the weaning period and while receiving a high-fat diet was accompanied by elevated gene expression levels of p21, resulting in decreased postnatal beta-cell mass expansion and compensatory beta-cell hyperplasia, respectively. In TG islets, proteomic analysis identified enhanced formation of various types of polyubiquitin chains, accompanied by increased expression of Nedd4 E3 ubiquitin protein ligase. Ubiquitination assays showed that UBE2E2 mediated the elongation of ubiquitin chains by Nedd4. The data suggest that UBE2E2-mediated ubiquitin modifications in beta-cells play an important role in regulating glucose homeostasis and beta-cell mass. |
