Histone Marks

H3K56ac

DNA entry–exit site — More DNA “breathing” without collapse; transcribed regions, newly made histones in S phase; low at telomeres; boosts chaperone (CAF1/Rtt106) binding

H3K64ac, H3K122ac, H3T118ph

Dyad axis (strongest histone–DNA contact) — Strong destabilization and eviction; active promoters

H4K91ac

Histone–histone interface — Destabilizes the octamer; replication / assembly

H3K79me

Histone–histone interface (outer surface) — Active transcription; creates a docking site (53BP1/Crb2)

H3K4me3

Active promoters; activation. Sits on unmethylated CpG islands. One half of a bivalent domain

H3K4me1

Active regulatory regions (enhancers)

H3K27ac

Active promoters and enhancers; activation

H3K27me3

Repression: facultative heterochromatin, inactive X, HOX genes. Other half of a bivalent domain

H3K9me3

Repression: constitutive heterochromatin. Exception: coding region of active genes (with HP1γ)

H3K9ac

Active chromatin; higher at the GR promoter in high-LG offspring (Weaver)

H3S10ph

Mitotic condensation; activation of immediate-early genes. Displaces HP1 from H3K9me3

H3K4me3 reader / key protein

BPTF (NURF); ING2 (can recruit a repressive HDAC complex)

H3K4me1 reader / key protein

WDR5

H3K27ac reader / key protein

Bromodomain proteins

H3K27me3 reader / key protein

Polycomb (PC2)

H3K9me3 reader / key protein

HP1 (chromodomain)

H3K9ac reader / key protein

Bromodomain proteins; removed by HDACs

H3S10ph reader / key protein

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