A mosaic analysis system with Cre or Tomato expression in the mouse

Area of Science:

• Genetics
• Cell Biology
• Oncology

Background:

• Somatic mutations are key drivers of cancer and age-related diseases.
• Studying early clonal growth of mutant cells is challenging due to limited experimental models.
• Understanding clonal abnormalities is crucial for disease pathogenesis research.

Purpose of the Study:

• To introduce a novel mosaic analysis system with Cre or Tomato (MASCOT) for tracking mutant cells.
• To demonstrate the utility of MASCOT in modeling clonal hematopoiesis and somatic mutations.
• To investigate the roles of Id3 and Tet2 genes in hematopoietic cell development and clonal expansion.

Main Methods:

• Development of the MASCOT system for simultaneous lineage tracing of mutant and reference cell populations.
• Mosaic analysis utilizing Cre-GFP or Tomato expression for cell tracking.
• Long-term tracking of hematopoietic cells with specific gene mutations (e.g., Tet2, Id3) in the MASCOT model.

Main Results:

• The MASCOT system demonstrated high sensitivity for detecting cell-intrinsic phenotypes in hematopoietic cells.
• Mosaic analysis revealed dynamic shifts in cell populations, from myeloid to lymphoid expansion, in Tet2-mutant and Tet2/Id3 double-mutant cells.
• The study observed the subsequent development of lymphoma in long-term tracked mutant cell populations.

Conclusions:

• The MASCOT system is a powerful tool for mosaic analysis of single or combined mutations.
• This method is suitable for modeling human somatic mutations and studying clonal hematopoiesis.
• The findings highlight the dynamic nature of clonal expansion and disease progression driven by specific genetic mutations.