Dataset Information

A Forward Genetic Screen Targeting the Endothelium Reveals a Regulatory Role for the Lipid Kinase Pi4ka in Myelo- and Erythropoiesis [clonality]

ABSTRACT: Definitive hematopoietic cells arise from hemogenic endothelium during mid-gestation, indicating a direct link between blood and the endothelial-lined vessels. We sought to determine whether mutations initiated in the hemogenic endothelium would yield hematopoietic abnormalities or malignancies. Here we demonstrate that transposon mutagenesis targeting endothelial cells in mice promotes the development of hematopoietic pathologies that are both myeloid and lymphoid in nature. Sequencing of the disrupted genes identified several previously recognized candidate cancer drivers and furthermore revealed that mutations in the lipid kinase Pi4ka can result in myeloid and erythroid dysfunction. Subsequent validation experiments showed that targeted inactivation of the Pi4ka catalytic domain or reduction in mRNA expression inhibited myeloid and erythroid cell differentiation in vitro and promoted anemia in vivo through a mechanism that includes, but it is not limited to deregulation of Akt signaling. Finally, we provide evidence linking PI4KAP2, previously considered a “pseudogene”, with human myeloid and erythroid leukemia.

ORGANISM(S): Mus musculus

PROVIDER: GSE108354 | GEO | 2018/01/30

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Human oncogenes involved in the development of hematological malignancies have been widely used to model experimental leukemia. Here, we used the fli1 promoter in zebrafish to target the expression of oncogenic HRAS to endothelial cells, including the hemogenic endothelium and observed the development of a myelo-erythroid proliferative disease. In larvae, the pathological phenotype is characterized by some disruption of the vascular system with prominent expansion of the caudal hematopoietic tissue, increase of expression of stem cell markers and myelo-erythroid specific genes and production of a large number of l-plastin leukocytes. In mosaic juveniles, increased number of hematopoietic blasts and arrest of myeloid maturation was found in kidney marrow. Peripheral blood showed delays of erythrocyte maturation and increased number of circulating myeloid progenitors. We found that the abnormal phenotype is associated with a down regulation of the Notch pathway as shown by the decrease of expression of Notch target genes, whereas overexpressing an activated form of Notch together with the oncogene prevents the expansion of the myelo-erythroid compartment. This study identifies the downregulation of the Notch pathway following an oncogenic event in the hemogenic endothelium as an important step in the pathogenesis of myelo-erythroid diseases and describes a number of potential effectors of this transformation. Methods: mRNA profiles of transgenic zebrafish overexpressing the oncogene HRAS in endothelial cells (Tg(fli1ep:GAL4FF)ubs3; Tg(UAS:eGFP-HRASV12)io006); or expressing activate Notch in endothelial cells (Tg(fli1ep:GAL4FF)ubs3; tg(UAS:NICD)kca3) were generated by deep sequencing using Illumina HiSeq 2000. The sequence reads that passed quality filters were analyzed using the CLC bio Assembly Cell software (version 3.2) and the Ensembl (release 63) predicted cDNAs for the Zv9 genome assembly. qRTM-bM-^@M-^SPCR validation was performed using TaqMan and SYBR Green assays.

Dataset Information

A Forward Genetic Screen Targeting the Endothelium Reveals a Regulatory Role for the Lipid Kinase Pi4ka in Myelo- and Erythropoiesis [clonality]

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure