Pdx1-CreERT2 Mouse

Pancreatic and duodenal homeobox 1 (PDX1) is a transcription factor encoded by a gene regulating pancreatic development and β-cell-specific gene expression. It is also the first molecular marker during the differentiation and maturation of pancreatic stem cells. Activation of the PDX1 gene promotes insulin release and the expression of important genes in β-cells, making it a necessary condition for differentiating pancreatic stem cells into pancreatic β-cells. Additionally, various signaling molecules, such as glucagon-like peptide 1 (GLP-1) and cytokines, synergistically regulate the expression of the PDX1 gene. PDX1 is specifically expressed in early pancreatic epithelium and plays a role in proliferation and differentiation during development. In the adult stage, PDX1 is essential for hormone production in β-cells.

The Pdx1-CreERT2 mouse is constructed by inserting the P2A-CreERT2 cassette upstream of the stop codon in the Pdx1 gene. Cre recombinase is expressed under the control of the mouse Pdx1 gene regulatory elements. Without tamoxifen treatment, CreERT2 recombinase primarily resides in the cytoplasm. Only when tamoxifen is administered does the CreERT2 recombinase enter the cell nucleus and exert its recombination activity. When Pdx1-CreERT2 mice are crossed with mice containing loxP sites, tamoxifen induction can trigger sequence recombination between loxP sites mediated by Cre recombinase in the pancreatic cells of the offspring. It’s important to note that without tamoxifen treatment, there may be restricted leakage of CreERT2 recombinase expression before induction.