H3K27ac - named in 40 entries with no entry of its own, and the strongest KMT2A::AFF1 measurement of it is invisible to every abstract search
also called H3K27ac · H3K27Ac · H3K27 acetylation · histone H3 lysine 27 acetylation · acetyl-H3K27
H3K27ac is the chemical tag that marks a gene switch (an enhancer) as switched on, and it is the most-used readout in the whole enhancer field. In leukaemia driven by a KMT2A fusion it has been measured directly - in cell lines, and in four patients including one infant - and the result is that a DOT1L inhibitor strips the tag off the fusion's own enhancers while leaving the rest of the genome untouched.
The same thing, for a scientist
H3K27ac is the acetyl mark on histone H3 lysine 27 that separates active from poised enhancers; it is written by EP300/CREBBP, erased by class I/II HDACs and the sirtuins, and read by bromodomain proteins including BRD4 and - directly relevant here - by the YEATS domains of AF9 and ENL, which bind H3K9ac strongly and H3K27ac more weakly [E5]. **The measurements that exist in KMT2A-rearranged disease are unusually good and unusually invisible.** In human SEM cells (a KMT2A::AFF1 / MLL-AF4 B-lineage ALL line) DOT1L inhibition decreases H3K27ac **exclusively at H3K79me2/3-marked enhancers (KEEs)**, with **no observed global change** [E1]; the same laboratory had already shown that MLL-AF4 knockdown reduces H3K27ac specifically at a BCL-2 3' enhancer bound by MLL-AF4 and P300 [E3]. H3K27ac ChIP-seq has been run on **four primary MLL-AF4 ALL patient samples, three childhood and one infant** [E2], and on THP-1 (MLL-AF9) and MV4-11 (MLL-AF4) AML lines, where fusion target genes carry H3K79me2, H3K27ac and H3K4me3 together [E4]. **The question this graph keeps asking - fusion targets or genome-wide - is answered cleanly and in the fusion-target direction, with the genome-wide negative control inside the same experiment** [E1]. What has never been measured is H3K27ac under a **pharmacological menin inhibitor**: a name-list-bounded query returns one record and it is a bioinformatic survey, and three menin-inhibitor chromatin papers read in full text carry no such measurement [E6].
Rule 80 in one table, on this mark
The bounded PubMed query (MLL-rearranged OR KMT2A-rearranged OR MLL-AF9 OR MLL-AF4 OR KMT2A OR "MLL fusion")[tiab] AND (H3K27ac OR "H3K27 acetylation")[tiab] returns 14 records on 2026-09-20. PMID 31243293 is not one of them - and that paper contains 49 occurrences of H3K27ac, an H3K27ac ChIP-seq experiment in SEM cells under DOT1L inhibition, and the central figure of this entry 1. Its abstract never names the mark.
| bound | what it covers | count |
|---|---|---|
| KMT2A term set alone | titles and abstracts | 3,209 |
H3K27ac[tiab] alone | titles and abstracts | 3,116 |
| the intersection | titles and abstracts | 14 |
| full texts of 14 core KMT2A-r chromatin papers, read for this entry | whole documents | 5 carry H3K27ac data, of which 1 is absent from the 14 |
A previous beat's ledger, ana-histone-mark-audit-rejected-candidates, declined to write this entry on the strength of the abstract intersection, describing the eleven records it then found as "all enhancer-landscape papers in which the mark is a readout rather than a subject". That judgement is wrong on its own terms for PMID 27856324, whose title is MLL-AF4 binds directly to a BCL-2 specific enhancer and modulates H3K27 acetylation - the mark is in the title and is the subject 3 - and it is wrong at the level of the corpus, because the strongest measurement in the disease was outside the count altogether. This is not a criticism of the counting. It is the demonstration that an abstract index cannot bound a claim about a measurement.
What is actually measured in a KMT2A-rearranged cell, and on what
SEM (human, KMT2A::AFF1, B-ALL), DOT1L inhibition. H3K27ac ChIP-seq plus ATAC-seq after DOT1L inhibitor treatment. H3K27ac falls only at KEEs - the subset of enhancers carrying H3K79me2/3 - while enhancers genome-wide are unchanged and there is no observed global change in H3K27ac. Worked examples are ARID1B, BCL11A and CDK6 (falling) against LMO4 and FOXO3 (unchanged) 1. A fusion-target-restricted result with an explicit genome-wide negative control inside the same experiment is rarer in this literature than it should be.
SEM, MLL-AF4 knockdown. Two clusters of H3K27Ac at the 3' end of BCL-2 constitute a BCL-2-specific enhancer, bound by MLL-AF4, P300 and wild-type E2A; loss of MLL-AF4 reduces both H3K79me3 in the gene body and H3K27Ac at that enhancer 3. A single locus, but it is the locus this graph's gene-bcl2 and venetoclax arguments run through.
Primary patients. Four primary MLL-AF4 ALL samples - three childhood and one infant - profiled for H3K4me1, H3K4me3, H3K27ac, H3K27me3, H3K79me2 and MLL-AF4 N-terminal occupancy, plus a published infant primograft 2. This is the only H3K27ac dataset in this disease that is not a cell line, and it is why the mark should not be written off as a cell-culture readout.
Myeloid comparators. In THP-1 (MLL-AF9) and MV4-11 (MLL-AF4) AML lines, both fusions' target genes carry H3K79me2, H3K27ac and H3K4me3, and the two fusions bind non-overlapping subsets of active distal elements while still driving a shared RUNX1 programme 4.
Writers, erasers and readers - and why the reader is partner-dependent
Writers. EP300 and CREBBP are the H3K27 acetyltransferases; both already have entries here (gene-ep300, gene-crebbp), and a 2024 study nominates them as therapeutic targets in MLL-rearranged AML [E6b]. P300 is physically present at the MLL-AF4-bound BCL-2 enhancer 3.
Erasers. HDACs and sirtuins. This graph carries gene-hdac1, gene-hdac2, gene-hdac3 and gene-sirt1. No H3K27ac-directed eraser has been measured at fusion targets in this disease; the SIRT1 work that exists is on H3K9ac and H4K16ac, and is written up in mark-h3k9ac.
Readers, and the finding worth carrying out of this entry. The AF9 YEATS domain binds H3K9ac strongly and H3K27ac and H3K18ac more weakly 5. The ENL YEATS domain binds H3 acetylated at K9, K18 and K27, and this graph has already established that it is retained by 84.1% of KMT2A::MLLT1 patients and required for leukaemogenesis (subtraction-mllt1-yeats-retained, mechanism-enl-yeats-acyl-reader-inside-the-kmt2a-mllt1-fusion), while the AF9 YEATS domain is discarded in about 92% of KMT2A::MLLT3 patients (subtraction-mllt3-yeats). So whether this mark has a dedicated reader inside the oncoprotein depends on which partner the patient carries. That is a mark-level statement the graph could not make while the mark had no entry, and it predicts that an acetyl-reader-directed intervention should separate t(11;19) from t(9;11) patients.
What is not established
No H3K27ac measurement exists under a pharmacological menin inhibitor. The name-list-bounded query returns one record, a bioinformatic survey of VSIR rather than a chromatin experiment 6; and three menin-inhibitor chromatin papers read in full text - PMC12632788 (menin plus LSD1 co-targeting in MLL-r AML), PMC11561541 (non-canonical menin targets and menin-inhibitor response) and PMC7614190 (menin inhibition and the KMT2A/polycomb balance) - contain H3K27ac 0, 0 and 2 times respectively, the two occurrences in the third being an antibody list and an H3K27ac ChIP performed in KELLY neuroblastoma cells under an EZH2 inhibitor. This is a bounded absence at the level of whole documents, not of abstracts. Three full texts is not the whole literature and the caveat says so.
No H3K27ac data exist in an infant KMT2A::AFF1 model. The infant data that exist are a primary sample and a primograft 2, not an engineered system, so the mark has never been followed through a controlled perturbation in the index disease's own developmental context.
None of these datasets is spike-in normalised. 'No global change' 1 is therefore a statement about a ratio-normalised ChIP and cannot exclude a uniform global shift. That limitation is shared with almost all pre-2020 histone ChIP-seq and is the one thing that would have to be redone before an H3K27ac pharmacodynamic assay could be built on it.
| mark | H3K27ac |
|---|---|
| histone | H3 |
| residue | K27, N-terminal tail |
| chemistry | acetylation (+42 Da); a steady state between writer and eraser turning over on a timescale of minutes - see mechanism-acetylation-is-a-cycle-not-a-mark |
| mutually exclusive with | H3K27me3 on the same histone tail |
| erasers class | class I/II HDACs and sirtuins; no H3K27ac-directed eraser has been measured at KMT2A-fusion targets |
| measured in kmt2a r | true |
| measured in kmt2a aff1 | true |
| measured in infant patient material | true |
| measurement scope | BOTH - locus-resolved at fusion-bound enhancers (PMIDs 31243293, 27856324, 37626123) AND with an explicit genome-wide negative control in the same experiment (PMID 31243293) |
| dot1l inhibitor effect | decrease restricted to KEEs; no observed global change (PMID 31243293, SEM cells) |
| menin inhibitor effect | never measured; bounded to 1 abstract-level record and 3 full texts read |
| spike in normalised | false |
| named in entries when written | 40 |
| mentions when written | 124 |
| count method | regex /\bH3K27ac/i over all 1,701 node JSON files, run 2026-09-20 |
| abstract query count 2026 09 20 | 14 |
| prior beat decision | ana-histone-mark-audit-rejected-candidates declined this entry on a 0.35% literature ratio; the arithmetic is reproduced here and the conclusion is revisited |
writers
[ "gene-ep300", "gene-crebbp" ]
readers
[ "gene-brd4 (bromodomain)", "gene-mllt1 ENL YEATS - retained in 84.1% of KMT2A::MLLT1", "gene-mllt3 AF9 YEATS - discarded in ~92% of KMT2A::MLLT3" ]
antibodies named in sources
[ "Abcam ab4729 (anti-H3K27ac; named in PMID 36635503)" ]
cell systems with data
[ "SEM (human, KMT2A::AFF1, B-ALL)", "MV4-11 (human, KMT2A::AFF1, AML)", "THP-1 (human, KMT2A::MLLT3, AML)", "4 primary MLL-AF4 ALL patients including 1 infant", "1 infant MLL-AF4 primograft" ]
abstract query misses
[ "31243293" ]
- Using a bulk H3K27ac immunoblot as a DOT1L-inhibitor pharmacodynamic assay would produce a confident negative from a drug that is working, because the published effect is restricted to KEEs and the bulk signal is explicitly unchanged.
- A p300/CBP inhibitor given to strip H3K27ac from fusion enhancers strips it from every enhancer in every dividing tissue; EP300 and CREBBP are broadly required and CREBBP is itself a haploinsufficient tumour suppressor in relapsed ALL, so lowering its activity is a plausible route to a worse relapse rather than a better one.
- A YEATS-domain inhibitor aimed at the acetyl reader is a t(11;19) drug and close to useless in t(9;11), because the AF9 YEATS domain is discarded in about 92% of KMT2A::MLLT3 patients - an unstratified trial would dilute a real effect to nothing.
- H3K27ac and H3K27me3 are mutually exclusive on the same tail, so any intervention raising one lowers the other at the same nucleosomes; combining an EZH2 inhibitor with a p300 inhibitor is pharmacologically self-cancelling at that residue and should not be proposed here without saying so.
- Does a pharmacological menin inhibitor move H3K27ac at fusion-bound enhancers, and if so at the same loci that lose H3K79me2? No published study has looked, at abstract level or in the three full texts read here.
- Is the KEE-restricted H3K27ac loss under DOT1L inhibition reproduced with spike-in normalisation? Every existing KMT2A-r H3K27ac dataset is ratio-normalised, so a uniform global shift would be invisible and would change 'locus-specific' into 'locus-specific on top of a global move'.
- Does H3K27ac at fusion-bound enhancers differ between t(11;19) (YEATS retained) and t(9;11) (YEATS discarded) patients? The reader is partner-dependent and nobody has profiled the mark across partners in matched material.
- Is the infant H3K27ac landscape different from the childhood one in KMT2A::AFF1? One infant sample and one primograft exist, and two is not a comparison.
- E1strong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.paper
In human SEM cells (a KMT2A::AFF1 / MLL-AF4 B-lineage ALL line), DOT1L inhibition causes a decrease in H3K27ac exclusively at H3K79me2/3-marked enhancers (KEEs) - exemplified at ARID1B, BCL11A and CDK6 - with no observed global change in H3K27ac and no change at non-KEE enhancers such as those at LMO4 and FOXO3.
DOT1L inhibition reveals a distinct subset of enhancers dependent on H3K79 methylation. · Godfrey L; Crump NT; Thorne R; Lau IJ; Repapi E; Dimou D; et al. · Nat Commun 2019What this evidence cannot show
Read in full text via the PMC HTML route (PMC6594956); the result is Fig. 3a-c with Supplementary Fig. 3a, and **the abstract never names H3K27ac**, so this paper is absent from the bounded abstract query that would otherwise be used to bound this mark. One cell line for the perturbation, one DOT1L inhibitor, no spike-in normalisation, so 'no global change' is a ratio-normalised statement. KEEs are defined by H3K79me2/3, so the claim is partly circular by construction: the enhancers that lose H3K27ac when H3K79me2/3 is removed are the ones selected for carrying H3K79me2/3.
Evidence that argues against this (1)
- The same laboratory's later work shows MLL-AF4-bound enhancers are a broader class than KEEs - MLL-AF4 binds 807 enhancers in SEM and the study profiles four patient samples - so a DOT1L-inhibitor-defined enhancer subset is not the same object as 'the fusion's enhancers', and an H3K27ac change restricted to KEEs is not evidence that fusion-bound enhancers in general are DOT1L-dependent. Crump NT; Smith AL; Godfrey L; Dopico-Fernandez AM; Denny N; Harman JR; et al. 2023
- E2strong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.paper
In four primary MLL-AF4 (KMT2A::AFF1) ALL patient samples - three childhood and one infant - together with a published infant primograft, H3K27ac was profiled by ChIP-seq/TOPmentation alongside H3K4me1, H3K4me3, H3K27me3, H3K79me2 and MLL-AF4 N-terminal occupancy, and MLL-AF4 binds a subset of H3K27ac-marked enhancers with high concordance in promoter binding across patients.
MLL-AF4 cooperates with PAF1 and FACT to drive high-density enhancer interactions in leukemia. · Crump NT; Smith AL; Godfrey L; Dopico-Fernandez AM; Denny N; Harman JR; et al. · Nat Commun 2023What this evidence cannot show
Read in full text (PMC10457349). n = 4 patients, one of them an infant, so the infant claim rests on a single sample plus one primograft; the authors combine ChIP-seq with TOPmentation rather than using one assay throughout, which is a material constraint of patient chromatin and not a design choice. The paper's subject is PAF1 and FACT, not H3K27ac, so here too the mark is a supporting readout rather than a titled result.
Evidence that argues against this (1)
- Patient-sample H3K27ac maps cannot separate fusion-driven acetylation from the acetylation landscape of the cell of origin, because no matched non-leukaemic counterpart from the same patient is profiled. The comparison of fusion-bound against unbound enhancers is made within the leukaemia, never against normal pro-B cells. Kerry J; Godfrey L; Repapi E; Tapia M; Blackledge NP; Ma H; et al. 2017
- E3strong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.paper
In human SEM cells (KMT2A::AFF1 / MLL-AF4 B-ALL), the BCL-2 3' enhancer consists of two clusters of H3K27Ac bound by MLL-AF4, P300 and wild-type E2A, and siRNA knockdown of MLL-AF4 reduces both H3K79me3 in the BCL-2 gene body and H3K27Ac at that enhancer.
MLL-AF4 binds directly to a BCL-2 specific enhancer and modulates H3K27 acetylation. · Godfrey L; Kerry J; Thorne R; Repapi E; Davies JO; Tapia M; et al. · Exp Hematol 2017What this evidence cannot show
Read in full text (PMC5333536). ChIP-qPCR at one locus after siRNA, so the direction is clear and the magnitude does not generalise; the P300 antibody is a polyclonal (Bethyl A300-358A) and no P300 catalytic perturbation is performed, so P300's presence at the enhancer is occupancy, not demonstrated causation. This is the one KMT2A-r paper with the mark in its title and it is a single-locus study.
Evidence that argues against this (1)
- The same enhancer is bound by P300 and marked by H3K27Ac in an E2A-PBX1 leukaemia line that carries no KMT2A rearrangement, so H3K27ac at the BCL-2 3' enhancer is not a fusion-specific feature; what the fusion changes is its maintenance, not its existence. Godfrey L; Kerry J; Thorne R; Repapi E; Davies JO; Tapia M; et al. 2017
- E4strong confidence 4 of 5: Replicated in peer-reviewed work by more than one group.paper
In THP-1 (MLL-AF9) and MV4-11 (MLL-AF4) human AML lines, MLL-AF9 and MLL-AF4 target genes are all marked by H3K79me2, H3K27ac and H3K4me3 together, and the two fusions additionally bind non-overlapping subsets of active distal regulatory elements while driving a shared RUNX1 programme.
MLL-AF9 and MLL-AF4 oncofusion proteins bind a distinct enhancer repertoire and target the RUNX1 program in 11q23 acute myeloid leukemia. · Prange KHM; Mandoli A; Kuznetsova T; Wang SY; Sotoca AM; Marneth AE; et al. · Oncogene 2017What this evidence cannot show
Read in full text (PMC5474565). Two cell lines, one per fusion, so 'MLL-AF9 versus MLL-AF4' is confounded with 'THP-1 versus MV4-11'; MV4-11 is an AML line carrying MLL-AF4, so this is not the B-lineage infant disease even though the fusion matches. The paper also documents that MEIS1 is neither bound nor expressed in THP-1, a cell-line drift caveat that applies to any THP-1 chromatin claim in this graph.
Evidence that argues against this (1)
- Co-occurrence of three active marks at fusion targets does not establish that the fusion deposits or maintains any of them; the KEE work shows that removing H3K79me2/3 moves H3K27ac at only a subset of these loci, so the three marks are not a single coupled unit. Godfrey L; Crump NT; Thorne R; Lau IJ; Repapi E; Dimou D; et al. 2019
- E5established confidence 5 of 5: Multiple independent lines of evidence; treated as settled in the field.paper
The AF9 (MLLT3) YEATS domain binds histone H3K9 acetylation strongly and H3K27 and H3K18 acetylation to a lesser extent, colocalises with H3K9 acetylation genome-wide by ChIP-seq, and that binding is important for chromatin recruitment of DOT1L.
AF9 YEATS domain links histone acetylation to DOT1L-mediated H3K79 methylation. · Li Y; Wen H; Xi Y; Tanaka K; Wang H; Peng D; et al. · Cell 2014What this evidence cannot show
The structural and binding work is in vitro with peptides and crystallography; the ChIP-seq colocalisation is in a human cell system and not in a KMT2A-rearranged cell. The affinity order is H3K9ac > H3K27ac/H3K18ac, so calling YEATS an 'H3K27ac reader' overstates it - and in the fusion context the AF9 YEATS domain is discarded in about 92% of KMT2A::MLLT3 patients, making this reader a property of wild-type AF9 far more often than of the oncoprotein.
Evidence that argues against this (1)
- The ENL YEATS domain, which IS retained by 84.1% of KMT2A::MLLT1 patients, has its H3K27ac affinity measured at a weak K_d of 66 uM by BLI in the work this graph records under mechanism-enl-yeats-acyl-reader-inside-the-kmt2a-mllt1-fusion, and reader-dead point mutants retain chromatin occupancy while losing leukaemic stem-cell frequency. A micromolar interaction that does not set localisation is a poor basis for calling H3K27ac the targeting signal. Li Y; Wen H; Xi Y; Tanaka K; Wang H; Peng D; et al. 2014
- E6established confidence 5 of 5: Multiple independent lines of evidence; treated as settled in the field.database
As of 2026-09-20 a drug-name-list-bounded PubMed query - ('menin inhibitor' OR 'menin inhibitors' OR 'menin inhibition' OR revumenib OR ziftomenib OR VTP-50469 OR VTP50469 OR MI-503 OR MI-2-2 OR bleximenib)[tiab] AND (H3K27ac OR H4K16ac OR H3K9ac OR H3K4me2 OR H3K9me3 OR 'H3.3' OR 'H2A.Z')[tiab] - returns 1 record, a bioinformatic survey rather than a chromatin measurement; the bare-operand control menin[tiab] AND H3K4me3[tiab] returns 42, and menin[tiab] against the same seven-mark set returns 11.
NCBI E-utilities esearch over PubMed, run 2026-09-20 by the Q59 marks2 beat, with every querytranslation read back and recorded · US National Library of Medicine 2026What this evidence cannot show
**Zero in titles and abstracts; supporting figures not searched by the query.** The bound was extended by reading three menin-inhibitor chromatin papers in full text - PMC12632788, PMC11561541 and PMC7614190 - in which H3K27ac occurs 0, 0 and 2 times, the two occurrences being an antibody list and an H3K27ac ChIP in KELLY neuroblastoma cells under an EZH2 inhibitor. Three full texts is not the whole menin-inhibitor literature. Rule 72 was applied: singular, plural and nominalisation were all included and hyphenated and unhyphenated compound codes treated as different strings. Every querytranslation was read back and none contained a [UID] term.
Evidence that argues against this (1)
- The absence is of the mark under the drug, not of chromatin work under the drug. Menin inhibition demonstrably moves H3K4me3 and H3K27me3 at bivalent genes, so the instruments and the cell systems exist and nobody has pointed an H3K27ac antibody at them. Sparbier CE; Gillespie A; Gomez J; Kumari N; Motazedian A; Chan KL; et al. 2023
- E6bmoderate confidence 3 of 5: One strong study, or several smaller consistent ones.paper
EP300 and CREBBP, the acetyltransferases that write H3K27ac, are nominated as therapeutic targets in MLL-rearranged acute myeloid leukaemia.
The epigenetic regulators EP300/CREBBP represent promising therapeutic targets in MLL-rearranged acute myeloid leukemia. · Wu W; Jiang Y; Xing D; Zhai Y; Sun H; He X; et al. · Cell Death Discov 2024What this evidence cannot show
Read at abstract level only. The paper is a target-nomination study in MLL-rearranged AML rather than a mechanistic account of H3K27ac at fusion targets, and EP300/CREBBP acetylate many non-histone substrates, so an EP300 dependency is not by itself an H3K27ac dependency. Myeloid, not the index B-lineage disease.
Evidence that argues against this (1)
- EP300 and CREBBP are broadly required across cancer lines and their loss has documented differentiation and DNA-damage consequences unrelated to enhancer acetylation at fusion targets, so target nomination on a growth phenotype does not localise the mechanism to H3K27ac. The MOF case in this disease makes the same point from the other side: a HAT dependency there runs through DNA damage repair, not through transcription at fusion targets. Valerio DG; Xu H; Chen CW; Hoshii T; Eisold ME; Delaney C; et al. 2017
THE ACETYLTRANSFERASE CONTACT ON THE DISCARDED SIDE: KMT2A's TAD-CBP contact is lost in the fusion, which bears on where H3K27ac at fusion targets comes from.
WHO READS IT INSIDE THE FUSION: the ENL YEATS domain reads H3K9/K18/K27 acylation and is retained in most t(11;19), a partner-dependent and menin-independent targeting route.
EP300 writes this mark and is bound at the MLL-AF4 BCL-2 enhancer
the paralogous H3K27 acetyltransferase; nominated with EP300 in MLL-r AML
ENL YEATS reads H3K9/K18/K27ac and is retained in 84.1% of KMT2A::MLLT1 patients
AF9 YEATS binds H3K27ac weakly (H3K9ac strongly) and is discarded in ~92% of KMT2A::MLLT3 patients
- ← regulatesKMT2A::AFF1 (MLL-AF4), t(4;11)(q21;q23)
MLL-AF4 knockdown reduces H3K27ac at the BCL-2 3' enhancer in SEM cells
- regulates →BCL2 — the one co-dependency in this beat that already has an approved drug pointed at it
two H3K27Ac clusters form the BCL-2-specific 3' enhancer in KMT2A::AFF1 cells
- ← causesPinometostat (EPZ-5676) — the DOT1L inhibitor, and the most instructive failure in this field
DOT1L inhibition lowers H3K27ac at KEEs only, with no observed global change (SEM)
maintenance of H3K27ac at KEEs requires H3K79me2/3
mutually exclusive on the same H3 tail
- part of →Plain-English: chromatin and epigenetics — the sticky notes on the DNA, and which ones matter here
layman explainer for the mark layer
this mark is a writer/eraser steady state, not a stable annotation
the patient-level H3K27ac maps in this disease come from the PAF1/FACT enhancer study
- expressed in →KMT2A-rearranged acute lymphoblastic leukaemia
profiled in four primary MLL-AF4 ALL patients including one infant
the prior ledger's abstract-ratio rejection of this mark; the strongest measurement was outside the count
same experiment, same cells: H3K9me3 up generally where H3K27ac falls at KEEs only
supplies the counted bound and the rule-80 rescue for this mark
the mark that defines the enhancers that entry is about
loss of enhancer H3R2me2a reduces H3K27ac and H3K4me1
the same block is 100% H3K27ac-covered at the BCR and the element in the same progenitor donor - active chromatin, not silent
The SEM H3K27ac replicate pairs agree at r=0.21-0.29 against H3K4me3's 0.79-0.83
WEAKEST STRAND, recorded with its limit: Flt3 is in the proto-oncogene set that gains CBP/p300 recruitment and histone ACETYLATION on conditional Hoxa9 activation at H3K4me1-marked distal enhancers. Murine, not a fusion system, and the acetylated residue is not specified in the source read here.
MEF2C's OUTPUT IS READ AS HISTONE ACETYLATION AT ITS OWN ENHANCERS: targeting LKB1 or SIK3 - whose substrate HDAC4 is a repressive MEF2C cofactor - diminishes histone acetylation at MEF2C-bound enhancers in AML. RESIDUE NOT SPECIFIED in the source, so this edge points at the acetylation family's representative node and must not be read as an H3K27ac-specific measurement.
UNC1999-driven Cdkn2a derepression couples H3K27me3 loss to a concurrent H3K27ac gain at distal elements
CBP writes H3K27ac; in MLL-rearranged AML the MLL-r-BET complex reads it at critical loci and A-485 blocks that, MLL-r-selectively
SET/TAF-I beta is an INHAT subunit that masks histones from p300/CBP and PCAF, so its readout on acetylation marks is negative