show Abstracthide AbstractWe generated mice with a mutation at threonine 58 of MYC in the mouse germline (T58A mutant). These mice ultimately develop AML or B cell lymphomas. We profiled changes in gene expression and genomic occupation of MYC in single cells of sorted, immature bone marrow progenitor cells, mature (spleen derived) and immature (marrow derived) B cells. B cells were stimulated with LPS and IL7, respectively. Overall design: Lineage negative, ckit+, Sca1+ cells were sorted from marrow of WT or T58A littermate mice, and profiled for expression and DNA accessibility by single cell RNA-Seq and ATAC-Seq using the 10X genomic system. Bulk RNA-Seq was also performed on immature B cells isolated from bone marrow, and stimulated with IL7. RNA-Seq was also done on mature B cells isolated from spleens of these animals, and stimulated with lipopolysaccharide (LPS). Genomic profiling was done using CUT&RUN to determine MYC occupation, and histone modifications (H3K27Ac and H3K4Me2) were carried out in both the LPS and IL7 treated cells. For scRNA-Seq, 2 paired, biological replicate experiments (LSK_1 and LSK_2, comparing sorted cells from WT and T58A mutant mice) were done for each genotype. Each replicate consisted of LSK cells from 2 mice of each genotype, for a total of 4 mice per genotype for this experiment. For all genomic profiling experiments (CUT&RUN), 2 biological replicates per genoype (mice) were performed.