Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A novel human fetal model of infant ALL reveals a link between MLL-AF4, PAF1 and increased H3K79me2/3 [RNA-seq]

ABSTRACT: Acute Lymphoblastic Leukemia (ALL) caused by chromosomal translocation involving the Mixed Lineage Leukemia (MLL) gene remains a poor prognosis disease, especially in infants. The most common MLL-rearrangement in infant ALL (iALL), MLL-AF4, originates in utero where the properties of fetal target cells likely provide a permissive landscape for transformation. We describe the first faithful MLL-AF4 iALL model derived by CRISPR-Cas9 genome editing of primary human fetal liver (FL) cells. Using this model, we demonstrate that H3K79me2/3 is increased during transformation as a direct consequence of MLL-AF4 binding, but correlates weakly with changes in gene expression. DOT1L, the only known H3K79 methyltransferase, does not form part of the MLL-AF4 complex. Instead, we identify PAF1 as a key protein recruited by the MLL-AF4 complex, which in turn can recruit DOT1L. These results explain the previously unclear link between MLL-AF4 binding and increased H3K79me2/3, and introduce an iALL-specific model for future drug studies.

ORGANISM(S): Homo sapiens

PROVIDER: GSE162032 | GEO | 2021/10/25

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

H3K79me2/3 controls enhancer promoter interactions and activation of the pan-cancer stem cell marker PROM1/CD133 in MLL-AF4 leukemia cells (ATAC-seq)

Project description:MLL gene rearrangements (MLLr) are a common cause of aggressive, incurable acute lymphoblastic leukemias (ALL) in infants and children, most of which originate in utero. The most common MLLr produces an MLL-AF4 fusion protein. MLL-AF4 promotes leukemogenesis by activating key target genes, mainly through recruitment of DOT1L and increased histone H3 lysine 79 methylation (H3K79me2/3). One key MLL-AF4 target gene is PROM1 which encodes CD133 (Prominin-1). CD133 is a pentaspan transmembrane glycoprotein that represents a potential pan-cancer target as it is found on multiple cancer stem cells. Here we demonstrate that aberrant PROM1/CD133 expression is essential for leukemic cell growth, mediated by direct binding of MLL-AF4. Activation is controlled by an intragenic H3K79me2/3 enhancer element (KEE) leading to increased enhancer-promoter interactions between PROM1 and the nearby gene TAPT1. This dual locus regulation is reflected in a strong correlation of expression in leukemia. We find that in PROM1/CD133 non-expressing cells, the PROM1 locus is repressed by polycomb repressive complex 2 (PRC2) binding, associated with reduced expression of TAPT1, partially due to loss of interactions with the PROM1 locus. Together, these results provide the first detailed analysis of PROM1/CD133 regulation that explains CD133 expression in MLLr ALL.

2020-03-25 | GSE135025 | GEO

H3K79me2/3 controls enhancer promoter interactions and activation of the pan-cancer stem cell marker PROM1/CD133 in MLL-AF4 leukemia cells (ChIP-seq)

2020-03-25 | GSE135024 | GEO

H3K79me2/3 controls enhancer promoter interactions and activation of the pan-cancer stem cell marker PROM1/CD133 in MLL-AF4 leukemia cells (RNA-seq)

2020-03-25 | GSE135023 | GEO

MLL-AF4 Spreading Identifies Binding Sites that Are Distinct from Super-Enhancers and that Govern Sensitivity to DOT1L Inhibition in Leukemia.

Project description:Understanding the underlying molecular mechanisms of defined cancers is crucial for effective personalized therapies. Translocations of the Mixed Lineage Leukemia (MLL) gene produce fusion proteins such as MLL-AF4 that disrupt epigenetic pathways and cause poor prognosis leukemias. Here we find that MLL-AF4 occupies a subset of unmethylated CG-enriched genes in combination with its cofactors Menin/LEDGF and ENL. MLL-AF4 mainly displays a punctate binding pattern near gene promoters, but we also observe a second less common pattern where MLL-AF4 spreads into the gene body and is associated with increased transcription and increased histone H3 lysine 79 methylation (H3K79me2/3). Compared to other H3K79me2/3 marked genes, MLL-AF4 spreading genes are more sensitive to inhibitors of the H3K79 methyltransferase DOT1L. This sensitivity mediates synergistic interactions with additional targeted drug treatments. Therefore, epigenetic spreading and enhanced susceptibility to epidrugs provides a potential new Achilles heel for guiding combination therapies in humans.

2017-01-12 | GSE83671 | GEO

MLL-AF4 binds directly to a BCL-2 specific enhancer and impacts H3K27 acetylation

Project description:Survival rates for children diagnosed with acute lymphoblastic leukemia (ALL) have drastically improved, but those carrying mutations in the Mixed Lineage Leukemia (MLL) gene continue to have a very poor prognosis. The most common MLL mutation in ALL is the t(4;11)(q21;q23) chromosome translocation that fuses MLL in frame with the AF4 gene producing MLL-AF4 and AF4-MLL fusion proteins. Previously, we showed that MLL-AF4 binds to the BCL-2 gene and directly activates it through DOT1L recruitment and increased H3K79me2/3 levels. We went on to show that MLL leukemias are particularly sensitive to treatment with the BCL-2 inhibitor venetoclax which synergizes with both standard chemotherapeutic agents as well as DOT1L inhibitors. Altered expression of other BCL-2 family members is a major cause of resistance to ventoclax, so here we perform a detalied analysis of MLL-AF4 regulation of the entire BCL-2 family. By measuring nascent RNA production, we find that of all the BCL-2 family genes, MLL-AF4 directly controls the transcription of both BCL-2 and MCL-1, but only BCL-2 shows a significant loss of steady state RNA levels. Interestingly however, both MCL-1 and BCL-XL protein levels are dependent on MLL-AF4 activity through an unknown and likely indirect mechanism. Finally, we analyze MLL-AF4 regulation of the BCL-2 gene in greater detail and using Capture C we identify a major BCL-2 specific enhancer consisting of two clusters of H3K27Ac. Loss of MLL-AF4 activity results in a reduction of H2K27Ac levels at the major BCL-2 enhancer, revealing a novel regulatory dependence on MLL-AF4 function at BCL-2.

2016-11-23 | GSE85988 | GEO

DOT1L inhibition reveals a distinct subset of enhancers dependent on H3K79 methylation (RNA-seq)

Project description:Enhancer elements are a key regulatory feature of many important genes. Several general features including the presence of specific histone modifications are used to demarcate potentially active enhancers. Here we reveal that putative enhancers marked with H3 lysine 79 (K79) di or trimethylation (me2/3) (which we name H3K79me2/3 enhancer elements or KEEs) can be found in multiple cell types. Mixed lineage leukemia gene (MLL) rearrangements (MLL-r) such as MLL-AF4 are a major cause of incurable acute lymphoblastic leukemias (ALL). Using the DOT1L inhibitor EPZ-5676 in MLL-AF4 leukemia cells, we show that H3K79me2/3 is required for maintaining chromatin accessibility, histone acetylation and transcription factor binding specifically at KEEs but not non-KEE enhancers. We go on to show that H3K79me2/3 is essential for maintaining enhancer-promoter interactions at a subset of KEEs. Together, these data implicate H3K79me2/3 as having a functional role at a subset of active enhancers in MLL-AF4 leukemia cells.

2019-05-30 | GSE128632 | GEO

DOT1L inhibition reveals a distinct subset of enhancers dependent on H3K79 methylation (Capture-C)

2019-05-30 | GSE117863 | GEO

DOT1L inhibition reveals a distinct subset of enhancers dependent on H3K79 methylation (ATAC-seq)

2019-05-30 | GSE117862 | GEO

DOT1L inhibition reveals a distinct subset of enhancers dependent on H3K79 methylation (ChIP-seq)

2019-05-30 | GSE117864 | GEO

Degree of Recruitment of DOT1L to MLL-AF9 Defines Level of H3K79 Di- and Tri-methylation on Target Genes and Transformation Potential

Project description:The MLL gene is a common target of chromosomal translocations found in human leukemia. MLL-fusion leukemias are consistently poor prognosis. One of the most common translocation partners is AF9 (a.k.a. MLLT3). MLL-AF9 recruits DOT1L, a histone 3 lysine 79 methyltransferase (H3K79me1/me2/me3), leading to aberrant gene transcription. We show that DOT1L has three AF9 binding sites, and present the NMR solution structure of a DOT1L-AF9 complex. We generated structure-guided point mutations with graded effects on recruitment of DOT1L to MLL-AF9. ChIP-Seq analyses of H3K79me2 and H3K79me3 show that graded reduction of the DOT1L interaction with MLL-AF9 results in selective losses in H3K79me2 and me3 marks at MLL-AF9 target genes. Furthermore, the degree of DOT1L recruitment defines the level of MLL-AF9 hematopoietic transformation. Hematopoietic progenitor cells isolated from mouse bone marrow were transduced with retrovirus expressing either wildtype MLL-AF9 (WT), mutants, MLL-AF9 (D544R) and MLL-AF9 (D546R). ChIP-Seq analyses were performed on these wildtype and mutant cells using H3K79me2 and H3K79me3 antibodies. 3 samples corresponding to ChIP-Seq with H3K79me2 antibody: 1) MLL-AF9 (WT) 2) MLL-AF9 (D544R) 3) MLL-AF9 (D546R) 3 Samples Corresponding to ChIP-Seq with H3K79me3 antibody: 4) MLL-AF9 (WT) 5) MLL-AF9 (D544R) 6) MLL-AF9 (D546R)

2015-04-30 | E-GEOD-64365 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data