scholarly journals Automated CUT&Tag profiling of chromatin heterogeneity in mixed-lineage leukemia

2021 ◽  
Author(s):  
Derek H. Janssens ◽  
Michael P. Meers ◽  
Steven J. Wu ◽  
Ekaterina Babaeva ◽  
Soheil Meshinchi ◽  
...  
Keyword(s):  
Single Cell ◽  
Binding Sites ◽  
Therapeutic Agents ◽  
Mixed Lineage Leukemia ◽  
Regulatory Proteins ◽  
Chromosomal Translocations ◽  
Tumor Subtype ◽  
Gene Encoding ◽  
Lysine Methyltransferase ◽  
Chromatin Profiling

AbstractAcute myeloid and lymphoid leukemias often harbor chromosomal translocations involving the KMT2A gene, encoding the KMT2A lysine methyltransferase (also known as mixed-lineage leukemia-1), and produce in-frame fusions of KMT2A to other chromatin-regulatory proteins. Here we map fusion-specific targets across the genome for diverse KMT2A oncofusion proteins in cell lines and patient samples. By modifying CUT&Tag chromatin profiling for full automation, we identify common and tumor-subtype-specific sites of aberrant chromatin regulation induced by KMT2A oncofusion proteins. A subset of KMT2A oncofusion-binding sites are marked by bivalent (H3K4me3 and H3K27me3) chromatin signatures, and single-cell CUT&Tag profiling reveals that these sites display cell-to-cell heterogeneity suggestive of lineage plasticity. In addition, we find that aberrant enrichment of H3K4me3 in gene bodies is sensitive to Menin inhibitors, demonstrating the utility of automated chromatin profiling for identifying therapeutic vulnerabilities. Thus, integration of automated and single-cell CUT&Tag can uncover epigenomic heterogeneity within patient samples and predict sensitivity to therapeutic agents.

scholarly journals Automated CUT&Tag profiling of chromatin heterogeneity in mixed-lineage leukemia

2020 ◽  
Author(s):  
Derek H. Janssens ◽  
Michael P. Meers ◽  
Steven J. Wu ◽  
Ekaterina Babaeva ◽  
Soheil Meshinchi ◽  
...  
Keyword(s):  
Single Cell ◽  
Fusion Proteins ◽  
Mixed Lineage Leukemia ◽  
Regulatory Proteins ◽  
Chromosomal Translocations ◽  
Fusion Partner ◽  
Activation Domains ◽  
Genome Wide ◽  
Lysine Methyltransferase ◽  
Acute Myeloid

AbstractAcute myeloid and lymphoid leukemias often harbor chromosomal translocations involving the Mixed Lineage Leukemia-1 gene, which encodes the KMT2A lysine methyltransferase. The most common translocations produce in-frame fusions of KMT2A to trans-activation domains of chromatin regulatory proteins. Here we develop a strategy to map the genome-wide occupancy of oncogenic KMT2A fusion proteins in primary patient samples regardless of fusion partner. By modifying the versatile CUT&Tag method for full automation we identify common and tumor-specific patterns of aberrant chromatin regulation induced by different KMT2A fusion proteins. Integration of automated and single-cell CUT&Tag uncovers lineage heterogeneity within patient samples and provides an attractive avenue for future diagnostics.

scholarly journals SiteOut: an online tool to design binding site-free DNA sequences

2015 ◽  
Author(s):  
Javier Estrada ◽  
Teresa Ruiz-Herrero ◽  
Clarissa Scholes ◽  
Zeba Wunderlich ◽  
Angela DePace
Keyword(s):  
Binding Site ◽  
Dna Sequences ◽  
Binding Sites ◽  
Regulatory Proteins ◽  
Biological Processes ◽  
Major Goal ◽  
Specific Sequence ◽  
Online Tool ◽  
Protein Binding Sites ◽  
Regulatory Dna

DNA-binding proteins control many fundamental biological processes such as transcription, recombination and replication. A major goal is to decipher the role that DNA sequence plays in orchestrating the binding and activity of such regulatory proteins. To address this goal, it is useful to rationally design DNA sequences with desired numbers, affinities and arrangements of protein binding sites. However, removing binding sites from DNA is computationally non-trivial since one risks creating new sites in the process of deleting or moving others. Here we present an online binding site removal tool, SiteOut, that enables users to design arbitrary DNA sequences that entirely lack binding sites for factors of interest. SiteOut can also be used to delete sites from a specific sequence, or to introduce site-free spacers between functional sequences without creating new sites at the junctions. In combination with commercial DNA synthesis services, SiteOut provides a powerful and flexible platform for synthetic projects that interrogate regulatory DNA. Here we describe the algorithm and illustrate the ways in which SiteOut can be used; it is publicly available at https://depace.med.harvard.edu/siteout/

scholarly journals TCF12 controls oligodendroglial cell proliferation and regulates signaling pathways conserved in gliomas

2021 ◽  
Author(s):  
Sofia Archontidi ◽  
Corentine Marie ◽  
Beata Gyorgy ◽  
Justine Guegan ◽  
Marc Sanson ◽  
...  
Keyword(s):  
Biological Processes ◽  
Oligodendrocyte Differentiation ◽  
Gene Encoding ◽  
Genome Wide ◽  
Diffuse Gliomas ◽  
Mrna And Protein Expression ◽  
Oligodendrocyte Precursor ◽  
Oligodendrocyte Development ◽  
Chromatin Profiling

Diffuse gliomas are primary brain tumors originating from the transformation of glial cells. In particular, oligodendrocyte precursor cells constitute the major tumor-amplifying population in the gliomagenic process. We previously identified the TCF12 gene, encoding a transcription factor of the E protein family, as being recurrently mutated in oligodendrogliomas. In this study, we sought to understand the function of TCF12 in oligodendroglial cells, the glioma lineage of origin. We first describe TCF12 mRNA and protein expression pattern in oligodendroglial development in the mouse brain. Second, by TCF12 genome wide chromatin profiling in oligodendroglial cells, we show that TCF12 binds active promoters of genes involved in proliferation, translation/ribosomes, and pathways involved in oligodendrocyte development and cancer. Finally, we perform OPC-specific Tcf12 inactivation in vivo and demonstrate by immunofluorescence and transcriptomic analyses that TCF12 is transiently required for OPC proliferation but dispensable for oligodendrocyte differentiation. We further show that Tcf12 inactivation results in deregulation of biological processes that are also altered in oligodendrogliomas. Together, our data suggest that TCF12 directly regulates transcriptional programs in oligodendroglia development that are relevant in a glioma context.

Abstract MP175: Disruption of the Genome Architecture at the PRRX1 Locus is Associated With the Pathogenesis of LMNA -related Dilated Cardiomyopathy

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Yuan Zhang ◽  
Mohamed Ameen ◽  
Isaac Perea Gil ◽  
Jennifer Arthur ◽  
Alexandra A Gavidia ◽  
...  
Keyword(s):  
Dilated Cardiomyopathy ◽  
Single Cell ◽  
Genome Organization ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Lamin A ◽  
Candidate Locus ◽  
Gene Encoding ◽  
Gene Dysregulation

Background: LMNA , a gene encoding A-type lamin proteins (abbreviated as lamin A), is one of the most frequently mutated genes in dilated cardiomyopathy (DCM). The molecular mechanisms underlying cardiomyocyte dysfunction in LMNA -related DCM remain elusive, translating to the lack of disease-specific therapies. Lamin A has been shown to play a critical role in genome organization via interactions with the chromatin at specific regions called lamina-associated domains (LADs). However, little is known about whether DCM-causing LMNA mutations rearrange the genome conformation and chromosome accessibility. The overarching goal of this study is to define the role of genome organization in LMNA -related DCM. Methods: LMNA -related DCM was modeled in vitro using cardiomyocytes derived from induced pluripotent stem cells (iPSC-CMs) from DCM patients carrying a frameshift mutation in the LMNA gene (c. 348_349insG; p. K117fs) and isogenic controls. We combined genome-wide single cell functional genomic and epigenomic mapping analyses to define the gene regulation and cis-regulatory interactions in isogenic iPSC-CMs. Results: Single-cell RNA-seq revealed global gene dysregulation in LMNA mutant compared to isogenic control iPSC-CMs. The homeodomain transcription factor PRRX1 was significantly upregulated in mutant cells. We showed that LAD integrity is disrupted at the PRRX1 locus in mutant iPSC-CMs. In agreement, DNA fluorescence in situ hybridization (FISH) revealed that the PRRX1 locus loses peripheral association and relocates towards the transcriptionally active nuclear interior in mutant iPSC-CMs. Correspondingly, single-cell assay for transposase accessible chromatin (ATAC)-seq showed increased chromatin co-accessibility at the PRRX1 locus, providing a plausible explanation for ectopic activation of PRRX1 in LMNA mutant iPSC-CMs. Conclusion: Our data suggest that LMNA haploinsufficiency disrupts the structure of LADs, leading to ectopic promoter interactions and altered gene expression in LMNA -related DCM iPSC-CMs. We identified PRRX1 as a promising candidate locus linking changes in LAD organization with gene dysregulation in LMNA -related DCM.

scholarly journals The SMC5/6 Complex Represses the Replicative Program of High-Risk Human Papillomavirus Type 31

Pathogens ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 786
Author(s):  
Ryan T. Gibson ◽  
Elliot J. Androphy
Keyword(s):  
Human Papillomavirus ◽  
High Risk ◽  
Viral Replication ◽  
Chromatin Immunoprecipitation ◽  
Binding Sites ◽  
Viral Infections ◽  
Hpv Infection ◽  
Regulatory Proteins ◽  
Transactivation Domain ◽  
Structural Maintenance Of Chromosomes

The multi-subunit structural maintenance of chromosomes (SMC) 5/6 complex includes SMC6 and non-SMC element (NSE)3. SMC5/6 is essential for homologous recombination DNA repair and functions as an antiviral factor during hepatitis B (HBV) and herpes simplex-1 (HSV-1) viral infections. Intriguingly, SMC5/6 has been found to associate with high-risk human papillomavirus (HPV) E2 regulatory proteins, but the functions of this interaction and its role during HPV infection remain unclear. Here, we further characterize SMC5/6 interactions with HPV-31 E2 and its role in the HPV life cycle. Co-immunoprecipitation (co-IP) revealed that SMC6 interactions with HPV-31 E2 require the E2 transactivation domain, implying that SMC5/6 interacts with full-length E2. Using chromatin immunoprecipitation, we found that SMC6 is present on HPV-31 episomes at E2 binding sites. The depletion of SMC6 and NSE3 increased viral replication and transcription in keratinocytes maintaining episomal HPV-31, indicating that SMC5/6 restricts the viral replicative program. SMC6 interactions with E2 were reduced in the presence of HPV-31 E1, suggesting that SMC6 and E1 compete for E2 binding. Our findings demonstrate SMC5/6 functions as a repressor of the viral replicative program and this may involve inhibiting the initiation of viral replication.

scholarly journals Identification of regulatory sequences and protein-binding sites in the liver-type promoter of a gene encoding 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.

1991 ◽  
Vol 11 (2) ◽  
pp. 1099-1106 ◽  
Author(s):  
F P Lemaigre ◽  
S M Durviaux ◽  
G G Rousseau
Keyword(s):  
Protein Binding ◽  
Binding Sites ◽  
Specific Protein ◽  
Regulatory Sequences ◽  
Alternative Promoters ◽  
Gene Encoding ◽  
Protein Binding Sites ◽  
Cis Acting ◽  
Dnase I Footprinting ◽  
Nuclear Extracts

The liver-type and muscle-type isozymes of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase are encoded by one gene that uses two alternative promoters. We have identified cis-acting sequences and protein-binding sites on the liver-type promoter. Transfection assays with deleted promoters showed that maximal promoter activity is contained within 360 bp upstream of the cap site. DNase I footprinting experiments with liver and spleen nuclear extracts and with purified proteins revealed several protein-binding sites in this region. These included four binding sites for nuclear factor I, one site that contains an octamer consensus but showed a liver-specific footprint pattern, two liver-specific protein-binding sites, and one poly(dG)-containing binding site. Transfection of cells of hepatic origin suggested that all these sites except one are involved in transcriptional regulation. The region between -360 and -2663 contained an element that functioned as a silencer in a nonhepatic cell line. We conclude that in liver transcription from the liver-type promoter of the 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase gene is controlled by ubiquitous and tissue-specific factors and involves activating and derepressing mechanisms.

scholarly journals Elucidating the druggable interface of protein−protein interactions using fragment docking and coevolutionary analysis

2016 ◽  
Vol 113 (50) ◽  
pp. E8051-E8058 ◽  
Author(s):  
Fang Bai ◽  
Faruck Morcos ◽  
Ryan R. Cheng ◽  
Hualiang Jiang ◽  
José N. Onuchic
Keyword(s):  
Drug Design ◽  
Protein Interactions ◽  
Binding Sites ◽  
Hot Spots ◽  
Therapeutic Agents ◽  
Molecular Probes ◽  
Therapeutic Drug ◽  
Protein Protein Interactions ◽  
Protein Surface ◽  
Fragment Docking

Protein−protein interactions play a central role in cellular function. Improving the understanding of complex formation has many practical applications, including the rational design of new therapeutic agents and the mechanisms governing signal transduction networks. The generally large, flat, and relatively featureless binding sites of protein complexes pose many challenges for drug design. Fragment docking and direct coupling analysis are used in an integrated computational method to estimate druggable protein−protein interfaces. (i) This method explores the binding of fragment-sized molecular probes on the protein surface using a molecular docking-based screen. (ii) The energetically favorable binding sites of the probes, called hot spots, are spatially clustered to map out candidate binding sites on the protein surface. (iii) A coevolution-based interface interaction score is used to discriminate between different candidate binding sites, yielding potential interfacial targets for therapeutic drug design. This approach is validated for important, well-studied disease-related proteins with known pharmaceutical targets, and also identifies targets that have yet to be studied. Moreover, therapeutic agents are proposed by chemically connecting the fragments that are strongly bound to the hot spots.

An enhancer region within the copia untranslated leader contains binding sites for Drosophila regulatory proteins

Gene ◽  
1998 ◽  
Vol 209 (1-2) ◽  
pp. 239-246 ◽  
Author(s):  
Susanne Wilson ◽  
Lilya V Matyunina ◽  
John F McDonald
Keyword(s):  
Binding Sites ◽  
Regulatory Proteins ◽  
Enhancer Region

scholarly journals The Mycobacterium tuberculosis TrcR Response Regulator Represses Transcription of the Intracellularly Expressed Rv1057 Gene, Encoding a Seven-Bladed β-Propeller

2006 ◽  
Vol 188 (1) ◽  
pp. 150-159 ◽  
Author(s):  
Shelley E. Haydel ◽  
Josephine E. Clark-Curtiss
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Intergenic Region ◽  
Binding Sites ◽  
Response Regulator ◽  
Transcriptional Start Site ◽  
Rich Region ◽  
Gene Encoding ◽  
Human Macrophages ◽  
Intracellular Expression ◽  
Transcribed Sequences

ABSTRACT The Mycobacterium tuberculosis TrcR response regulator binds and regulates its own promoter via an AT-rich sequence. Sequences within this AT-rich region determined to be important for TrcR binding were used to search the M. tuberculosis H37Rv genome to identify additional related TrcR binding sites. A similar AT-rich sequence was identified within the intergenic region located upstream of the Rv1057 gene. In the present work, we demonstrate that TrcR binds to a 69-bp AT-rich sequence within the Rv1057 intergenic region and generates specific contacts on the same side of the DNA helix. An M. tuberculosis trcRS deletion mutant, designated STS10, was constructed and used to determine that TrcR functions as a repressor of Rv1057 expression. Additionally, identification of the Rv1057 transcriptional start site suggests that a SigE-regulated promoter also mediates control of Rv1057 expression. Using selective capture of transcribed sequences (SCOTS) analysis as an evaluation of intracellular expression, Rv1057 was shown to be expressed during early M. tuberculosis growth in human macrophages, and the Rv1057 expression profile correlated with a gene that would be repressed by TrcR. Based on structural predictions, motif analyses, and molecular modeling, Rv1057 consists of a series of antiparallel β-strands which adopt a β-propeller fold, and it was determined to be the only seven-bladed β-propeller encoded in the M. tuberculosis genome. These results provide evidence of TrcR response regulator repression of the Rv1057 β-propeller gene that is expressed during growth of M. tuberculosis within human macrophages.

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