GSE131725
Cyba deficient mice display an increase of Haematopoietic Stem Cells, and a myeloid bias in detriment of B-cell differentiation
The regulation of protein function by reversible oxidation is increasingly recognized as a key mechanism for the control of cellular signalling, modulating crucial biological processes such cell differentiation. In this scenario, the NADPH oxidases must occupy a prominent position. Our results show that haematopoietic stem and progenitor cells (HSPCs) express three p22phox-dependent NADPH oxidases members (Nox1, Nox2 and Nox4). By deleting the p22phox coding gene (Cyba), here we have analysed the importance of this family of enzymes during in vivo haematopoiesis. Cyba-/- mice show a myeloid bias in detriment of B-cells differentiation, and an enrichment of HSPCs populations. By means of haematopoietic transplant experiments we have also tried to dissect the specific role of the NADPH oxidases. While the absence of Nox1 or Nox2 provides an advantage of reconstitution, the lack of Nox4 rendered the opposite result, what suggests a functional specificity among the different NADPH oxidases. Regarding signalling pathways, the activation of AKT and STAT5 is hampered in Cyba-/- cells, the later due to the downregulation of STAT5 protein. This is in line with the diminished response to IL-7 shown by our results, what could explain defective B-cells development observed in Cyba-/- mice, supporting the requirement of NADPH oxidase activity for terminal B-cell differentiation. Overall design: Total mRNA from bone marrow Lineage negative cells of 2 wild type (WT) and 2 Cyba-/- mice were analized