MYSM1 is a transcriptional regulator essential for HSC function and hematopoiesis. We established that HSC dysfunction in Mysm1-deficiency is driven by p53 stress response, however, the molecular function of MYSM1 as a transcriptional activator and its essential role in p53 stress response repression remain difficult to reconcile. Here, we performed genome-wide analyses of MYSM1-regulated genes in hematopoietic stem and progenitor cells (HSPCs). This included RNA-Seq of sorted Mysm1-deficient mouse HSCs and MPPs, and ChIP-Seq mapping of MYSM1 DNA-binding sites in hematopoietic progenitor cell lines. We demonstrate a direct role for MYSM1 in the regulation of genes encoding protein components of the ribosome (RP-genes) and other regulators of translation. Mechanistically, the dysregulation of RP-genes in Mysm1-deficiency was upstream of p53-activation and associated with reduced HSCs protein synthesis rates and p53-dependent anemia. SOURCE: David Langlais (david.langlais@mcgill.ca) - Inflammation Genomics Lab McGill University

Pluto Bioinformatics

GSE150666: MYSM1 maintains ribosomal protein gene expression in hematopoietic stem cells to prevent hematopoietic dysfunction II.