Specific Temporal Requirement of Prox1 Activity During Pancreatic Acinar Cell Development.

Area of Science:

• Developmental biology
• Molecular biology
• Genetics

Background:

• Pancreatic acinar cell maturation is governed by a regulatory network of transcription factors.
• The transcription factor Prox1 is expressed in pancreatic progenitors but not mature acinar cells.
• Understanding Prox1's role is key for directed pancreatic differentiation protocols.

Purpose of the Study:

• To determine when Prox1 expression ceases in developing acinar cells.
• To investigate Prox1's role in acinar cell specification and differentiation.
• To assess the impact of sustained Prox1 expression on acinar cell maturation and maintenance.

Main Methods:

• Immunofluorescence and confocal microscopy to analyze Prox1 expression.
• Utilized Prox1-null and Prox1 transgenic mouse models.
• Employed histological, immunostaining, electron microscopy, functional assays, and RNA/RNA-sequencing.

Main Results:

• Prox1 shows transient expression in newly committed embryonic acinar cells.
• Prox1-null embryos exhibited precocious expression of late acinar genes.
• Prox1-null adult mice displayed severe pancreatic alterations, including atrophy and inflammation.

Conclusions:

• Transient Prox1 expression is essential for correct sequential gene expression during acinar cell development.
• Termination of Prox1 expression is required for acinar cell maturation and homeostasis.
• Sustained Prox1 expression in transgenic mice did not impede normal pancreas development.