Abstract: SA-OR16
Sall1-NuRD Cooperate in Nephron Progenitor Cells to Determine Cell Fate
Session Information
- Bioengineered Model Systems and Insights in Kidney Development and Function
October 26, 2024 | Location: Room 2, Convention Center
Abstract Time: 05:30 PM - 05:40 PM
Category: Development, Stem Cells, and Regenerative Medicine
- 600 Development, Stem Cells, and Regenerative Medicine
Authors
- Basta, Jeannine M., Washington University in St Louis, St Louis, Missouri, United States
- Robbins, Lynn, VA Medical Center, St. Louis, Missouri, United States
- Stout, Lisa, Washington University in St Louis, St Louis, Missouri, United States
- Brennan, Michelle, Saint Louis University, St Louis, Missouri, United States
- Rauchman, Michael I., Washington University in St Louis, St Louis, Missouri, United States
Background
We created a knock-in mutant mouse (ΔSRM) that disrupts the interaction between the transcription factor Sall1 and the NuRD chromatin remodeling complex, resulting in accelerated nephron progenitor cell (NPC) differentiation, renal hypoplasia, and altered progenitor cell fate [Basta et al, Development (2017) 144 (17): 3080–3094].
Methods
To investigate the molecular mechanisms responsible for the altered cell fate of ΔSRM NPCs, we performed CUT&RUN in wild type and mutant NPCs, and 10X single-cell multiome experiments (RNA-seq and ATAC-seq in the same cell) in wild type and mutant kidney.
Results
In wild type NPCs NuRD components Mi2b and Mbd3 bound 76% of promoters also bound by Sall1. In ΔSRM NPCs Sall1-NuRD common binding at promoters is reduced 50% compared to wild type NPCs. Reduced binding of Sall1-NuRD components was observed at both progenitor genes (Cited1, Meox2, Crym) and genes induced with nephron differentiation (Notch1, Pax8). E17 multiome data revealed decreased expression of progenitor genes and upregulation of genes associated with nephron differentiation (Notch1, Pax8) in the mutant NPC cluster.
Conclusion
Loss of Sall1-NuRD binding in mutants suggests that Sall1-NuRD maintains the balance between self-renewal and differentiation by directly maintaining expression of progenitor genes and restricting activation of genes induced by differentiation signals. Our multiome data revealed that Six2+ cells in the mutant NPC cluster exhibited a mixed lineage phenotype in which some progenitor genes are reduced in expression while differentiation marker genes (Pax8, Notch1) are ectopically activated.
10X multiome gene expression (left), orange circle highlighting NPC cluster, showing retained Six2, decreased Cited1, Crym, and ectopic Pax8 expression in mutant NPCs. CUT&RUN in control and mutant NPCs (right), blue box highlighting promoter region of Cited1, showing reduced binding of Mi2b, Mbd3, and Sall1 (arrows) in mutant NPCs.
Funding
- NIDDK Support