GalNT2-mediated O-glycosylation affects pancreas development and function in mice

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• GALNT2 (polypeptide N-acetylgalactosaminyltransferase 2) is key in O-linked glycosylation, impacting protein function.
• Dysregulation of GALNT2 is linked to diseases like cancer and metabolic disorders.

Purpose of the Study:

• To investigate the in vivo effects of GALNT2 overexpression in the pancreas for the first time.
• To explore the role of GALNT2 in pancreatic cell fate and adipocyte differentiation.

Main Methods:

• Generated a conditional transgenic mouse model for pancreas-specific GALNT2 overexpression.
• Utilized a reporter gene mouse line to track cell differentiation.
• Performed PNA lectin enrichment and mass spectrometric proteome analysis.

Main Results:

• Heterozygous GALNT2 overexpression led to pancreatic acinar mass loss and steatosis.
• Homozygous GALNT2 overexpression resulted in complete pancreatic loss and lethality.
• Demonstrated adipocyte transdifferentiation from pancreatic cells due to GALNT2 overexpression.
• Identified increased O-glycosylation sites upon GALNT2 overexpression.

Conclusions:

• GALNT2 overexpression profoundly disrupts pancreatic structure and function.
• GALNT2 plays a critical role in regulating pancreatic cell identity and potentially driving adipogenesis.
• Altered O-glycosylation patterns are a consequence of GALNT2 overexpression.