Although the developing pancreas is exquisitely sensitive to nutrient supply in utero, it is not entirely clear how nutrient-driven post-translational modification of proteins impacts the pancreas during development. We hypothesized that the nutrient-sensing enzyme O-GlcNAc transferase (Ogt), which catalyzes an O-GlcNAc-modification onto key target proteins, integrates nutrient-signaling networks to regulate cell survival and development. In this study, we investigated the heretofore unknown role of Ogt in exocrine and endocrine islet development. By genetic manipulation in vivo and by using morphometric and molecular analyses, such as immunofluorescence imaging and single cell RNA sequencing, we show the first evidence that Ogt regulates pancreas development. Genetic deletion of Ogt in the pancreatic epithelium (OgtKOPanc) causes pancreatic hypoplasia, in part by increased apoptosis and reduced levels of of Pdx1 protein. Transcriptomic analysis of single cell and bulk RNA sequencing uncovered cell-type heterogeneity and predicted upstream regulator proteins that mediate cell survival, including Pdx1, Ptf1a and p53, which are putative Ogt targets. In conclusion, these findings underscore the requirement of O-GlcNAcylation during pancreas development and show that Ogt is essential for pancreatic progenitor survival, providing a novel mechanistic link between nutrients and pancreas development.
Bibliographical noteFunding Information:
This research was supported by the National Institutes of Health (R01DK115720, R21DK112144 and R03DK114465 to E.U.A, T32 5T32DK007203-40 to S.P., R03DK114465-01A1S1 to B.A.); the University of Minnesota Foundation; the McKnight Foundation, the University of Minnesota Genomics Center; and by the Minnesota Supercomputing Institute for the analysis of the single-cell RNAseq data. Deposited in PMC for release after 12 months.
- Hexosamine biosynthetic pathway
- Islet development
- O-GlcNAc Transferase
- Pancreas development