TY - JOUR
T1 - Overexpression of Pdx1, reduction of p53, or deletion of CHOP attenuates pancreas hypoplasia in mice with pancreas-specific O-GlcNAc transferase deletion
AU - Wong, Alicia
AU - Pritchard, Samantha
AU - Moore, Mackenzie
AU - Akhaphong, Brian
AU - Avula, Nandini
AU - Beetch, Megan
AU - Fujitani, Yoshio
AU - Alejandro, Emilyn U.
N1 - Publisher Copyright:
© 2023
PY - 2023/2
Y1 - 2023/2
N2 - Deletion of O-GlcNAc transferase (Ogt) in pancreatic epithelial progenitor cells results in pancreatic hypoplasia at birth, partly due to increased apoptosis during embryonic development. Constitutive loss of Ogt in β-cells results in increased ER stress and apoptosis, and in the Ogt-deficient pancreas, transcriptomic data previously revealed both tumor suppressor protein p53 and pancreatic duodenal homeobox 1 (Pdx1), key cell survival proteins in the developing pancreas, as upstream regulators of differentially expressed genes. However, the specific roles of these genes in pancreatic hypoplasia are unclear. In this study, we explored the independent roles of p53, ER stress protein CHOP, and Pdx1 in pancreas development and their use in the functional rescue of pancreatic hypoplasia in the context of Ogt loss. Using in vivo genetic manipulation and morphometric analysis, we show that Ogt plays a key regulatory role in pancreas development. Heterozygous, but not homozygous, loss of pancreatic p53 afforded a partial rescue of β-cell, α-cell, and exocrine cell masses, while whole body loss of CHOP afforded a partial rescue in pancreas weight and a full rescue in exocrine cell mass. However, neither was sufficient to fully mitigate pancreatic hypoplasia at birth in the Ogt-deficient pancreas. Furthermore, overexpression of Pdx1 in the pancreatic epithelium resulted in partial rescues in pancreas weight and β-cell mass in the Ogt loss background. These findings highlight the requirement of Ogt in pancreas development by targeting multiple proteins such as transcription factor Pdx1 and p53 in the developing pancreas.
AB - Deletion of O-GlcNAc transferase (Ogt) in pancreatic epithelial progenitor cells results in pancreatic hypoplasia at birth, partly due to increased apoptosis during embryonic development. Constitutive loss of Ogt in β-cells results in increased ER stress and apoptosis, and in the Ogt-deficient pancreas, transcriptomic data previously revealed both tumor suppressor protein p53 and pancreatic duodenal homeobox 1 (Pdx1), key cell survival proteins in the developing pancreas, as upstream regulators of differentially expressed genes. However, the specific roles of these genes in pancreatic hypoplasia are unclear. In this study, we explored the independent roles of p53, ER stress protein CHOP, and Pdx1 in pancreas development and their use in the functional rescue of pancreatic hypoplasia in the context of Ogt loss. Using in vivo genetic manipulation and morphometric analysis, we show that Ogt plays a key regulatory role in pancreas development. Heterozygous, but not homozygous, loss of pancreatic p53 afforded a partial rescue of β-cell, α-cell, and exocrine cell masses, while whole body loss of CHOP afforded a partial rescue in pancreas weight and a full rescue in exocrine cell mass. However, neither was sufficient to fully mitigate pancreatic hypoplasia at birth in the Ogt-deficient pancreas. Furthermore, overexpression of Pdx1 in the pancreatic epithelium resulted in partial rescues in pancreas weight and β-cell mass in the Ogt loss background. These findings highlight the requirement of Ogt in pancreas development by targeting multiple proteins such as transcription factor Pdx1 and p53 in the developing pancreas.
KW - CHOP
KW - ER stress
KW - O-GlcNAc transferase
KW - O-GlcNAcylation
KW - Pdx1
KW - beta-cell
KW - islet
KW - p53
KW - pancreas development
KW - transcription factors
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UR - http://www.scopus.com/inward/citedby.url?scp=85147550336&partnerID=8YFLogxK
U2 - 10.1016/j.jbc.2023.102878
DO - 10.1016/j.jbc.2023.102878
M3 - Article
C2 - 36623733
AN - SCOPUS:85147550336
SN - 0021-9258
VL - 299
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 2
M1 - 102878
ER -