GSE174533
Lamin B1 deletion in myeloid neoplasms alters hematopoietic cell fate and causes Pelger-Huët nuclear anomaly
The most common cytogenetic abnormality found in complex karyotype high risk MDS/AML is del5q. Disease is often identified through visual inspection and recognition of abnormalities such as pseudo-Pelger-Huet anomaly (PPHA), which presents as deviations of normal neutrophil nuclear morphology. The link between PPHA and leukemia is unknown, but mutations in the lamin B1 receptor (LBR) have been identified as the cause of benign presence in otherwise normal individuals. Lamin B1 (LMNB1) is the ligand for LBR and is important for maintaining nuclear lamina integrity and influencing 3D gene structural changes that impact transcription; the LMNB1 gene locus is also contained with chromosome 5q, so we hypothesized that appearance of PPHA is potentially caused by del5q in MDS/AML containing the LMNB1. To help characterize the potential role of LMNB1 in normal hematopoietic stem and progenitor cells (HSPCs), we infected CD34+ cord blood HSPCs with lentiviruses expressing shRNAs targeting LMNB1 (LB1) and luciferase (C11) as a control and assessed changes in transcription due to LMNB1 disruption via RNSeq and 3D genome structural changes through HiC. Neutrophils were also differentiated from LMNB1 shRNA and control treated CD34+ cord blood HSPCs and transcriptional/structural changes identified via RNAseq and HiC. Additionally, to understand long-term in vivo effects of LMNB1 loss on self-renewal and lineage bias, we engrafted control and LMNB1 shRNA infected CD34+ HSPCs into NSG mice and harvest hCD34+ cells 12 weeks later for scRNAseq. Overall design: RNAseq, HiC, and 10X genomics scRNAseq