The alternative Nucleosome Remodeling Factor complex sustains acute myeloid leukemia by regulating the accessibility of insulator regions
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE226688 | GEO | 2023/11/11
REPOSITORIES: GEO
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Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent advances. Here using a CRISPRi screen targeting chromatin factors, we identified BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader modules of BPTF, while contributing to complex recruitment to chromatin, are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
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Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent therapeutic advances. Here, using a CRISPRi screen targeting chromatin factors, we identified the nucleosome-remodeling factor (NURF) subunit BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader domains of BPTF, while contributing to complex recruitment to chromatin, are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
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Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent advances. Here using a CRISPRi screen targeting chromatin factors, we identified BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader modules of BPTF are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
2023-11-11 | GSE226673 | GEO
Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent advances. Here using a CRISPRi screen targeting chromatin factors, we identified BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader modules of BPTF are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
2023-11-11 | GSE226671 | GEO
Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent advances. Here using a CRISPRi screen targeting chromatin factors, we identified BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader modules of BPTF are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
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Project description:Efficient treatment of Acute Myeloid Leukemia (AML) patients remains a challenge despite recent advances. Here using a CRISPRi screen targeting chromatin factors, we identified BPTF as an essential regulator of AML cell survival. We demonstrate that BPTF forms an alternative NURF chromatin remodeling complex with SMARCA5 and BAP18, which regulates the accessibility of a large set of insulator regions in leukemic cells. This ensures efficient CTCF binding and boundary formation between topologically associated domains that is essential for maintaining the leukemic transcriptional programs. We also demonstrate that the well-studied PHD2-BROMO chromatin reader modules of BPTF are dispensable for leukemic cell growth. Taken together, our results uncover how the alternative NURF complex contributes to leukemia and provide a rationale for its targeting in AML.
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Project description:Plants as sessile organisms can adapt to environmental stress to mitigate its adverse effects. As part of such adaptation they maintain an active memory of heat stress for several days that mediates a more efficient response to recurring stress. We identified a mutant that is specifically affected in this heat stress memory. The forgetter1 (frg1) mutant is defective in the Arabidopsis orthologue of Strawberry notch and displays reduced maintenance of heat-induced gene expression. FRG1 globally associates with the promoter region of actively expressed genes in a heat-dependent fashion. FRG1 interacts with chromatin remodelers of the SWI/SNF and ISWI families, which also display reduced heat stress memory. Accordingly, nucleosome dynamics at loci with altered maintenance of heat-induced expression are affected in frg1. Thus, FRG1 is required to sustain a transcription-competent chromatin environment by nucleosome positioning. Our findings suggest a mechanism for the highly conserved Strawberry notch proteins in development and pathologies.
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