INTEGRATED MULTI-OMICS ANALYSIS OF PBX1 IN MOUSE ADULT NEURAL STEMAND PROGENITOR CELLS IDENTIFIES A TRANSCRIPTIONAL MODULE WITH RELEVANCE TO LEUKEMOGENESIS

ABSTRACT: Developmental transcription factors act in networks, but how these networks achieve cell- and tissue specificity is still poorly understood. We here explored pre-B-cell leukemia homeobox 1 (PBX1) in adult neurogenesis combining genomic, transcriptomic, and proteomic approaches. ChIP-Seq analysis uncovered PBX1 binding to a wide range of different genes. Integration of PBX1 ChIP-seq with ATAC-seq data predicted interaction partners, which were subsequently validated by mass-spectrometry. Spatial transcriptomics revealed distinct temporal expression dynamics of Pbx1 and interacting factors. Among these were class I bHLH proteins TCF3, TCF4 and TCF12. RNA-seq upon Pbx1, Tcf3 and Tcf4 knockdown identified proliferation and differentiation associated genes as shared targets. Neuronal differentiation was reduced upon depletion of either factor, suggesting functional cooperation between PBX1 and TCF3/4. Notably, while physiological PBX1-TCF interactions have not yet been described, chromosomal translocation resulting in genomic TCF3::PBX1 fusion characterizes a subtype of acute lymphoblastic leukemia. Introducing Pbx1 into Nalm6 cells, a pre B-cell line expressing TCF3 but lacking PBX1, upregulated leukemogenic genes including BLK and NOTCH3, arguing that functional PBX1-TCF cooperation likely extends to hematopoietic contexts. Our study hence uncovers a PBX1-TCF module orchestrating the balance between progenitor cell proliferation and differentiation in adult neurogenesis with implications for leukemia etiology.

INSTRUMENT(S): timsTOF Pro 2

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Brain

SUBMITTER: Julian Langer  

LAB HEAD: Julian Langer

PROVIDER: PXD048222 | Pride | 2024-09-16

REPOSITORIES: Pride