Table 2.

Classification and characteristics of histone deacetylases.

Class type	Class I	Class IIa	Class IIb	Class III	Class IV
Human HDAC	HDAC-1, -2, -3, -8	HDAC-4, -5, -7, -9	HDAC-6, -10	SIRT1−7	HDAC11
Yeast homolog	RPD3	HDA1	HDA1	SIR2	RPD3
Subcellular localization	Nucleus	Nucleus/cytoplasm	Mostly cytoplasm	Nucleus	Nucleus/cytoplasm
Tissue distribution	Ubiquitous	Brain, heart, skeletal muscle	Liver, Kidney, spleen, pancreas	Unknown	Brain, heart, skeletal muscle, kidney
Substrates (partial list)	Histones, p53, E2F1, STAT1, STAT3, NF-κB, GATA1, YY1, MyoD, SHP, RelA, MEF2D, AR, GR	Histones, GATA1, HP-1, SMAD7, PLAG1, PLAG2, GCMa	Histones, tubulin, HSP90, SHP, SMAD7	Histones, tubulin, p53	Unknown
Associated protein complexes (partial list)	NuRD, SIN3, CoREST, NCoR, SMRT	NCoR, SMRT		PcG (PRC4)
Binding partners (partial list)	RB, BRCA1, DNMT1, DNMT3a, DNMT3b, MBD2−3, MeCP2, ATM	HIF-1α, BCL-6, actinin, AR, ER, MEF2	RUNX2
Cofactor	Zn	Zn	Zn	NAD+	Zn

AR: Androgen receptor; ATM: Ataxia telangiectasia mutated; BCL-6: B-cell lymphoma 6; BRCA1: Breast cancer 1, early onset; CoREST: Corepressor for element-1-silencing transcription factor; DNMT1: DNA methyltransferase 1; ER: Estrogen receptor; GATA1: GATA binding protein 1; GCMa: Glial cells missing homolog α; GR: Glucocorticoid receptor; HDAC1: Histone deacetylase 1; HIF-1a: Hypoxia-inducible factor-1α; HP-1: Heterochromatin protein 1; HSP90: Heat shock protein 90; MBD2−3: Methyl-CpG binding domain 2−3; MeCP2: Methyl-CpG binding protein 2; MEF2: Myelin expression factor 2; MEF2D: Myocyte enhancer factor 2D; MyoD: Myogenic differentiation 1; NCoR: Nuclear receptor corepressor; NuRD: Nucleosome remodelling and histone deacetylase; PcG: Polycomb group; PLAG1−2: Pleiomorphic adenoma gene 1−2; RB: Retinoblastoma; RelA: v-rel reticuloendotheliosis viral oncogene homolog A; RPD3: Reduced potassium deficiency 3; RUNX2: Runt-related transcription factor 2; SHP: Small heterodimer partner; SIN3: SWI-independent 3; SIR2: Silencing information regulator 2; SMAD7: Mothers against decapentaplegic homolog 7; SMRT: Silencing mediator for retinoid and thyroid hormone receptors; STAT-1 and -3: Signal transducers and activators of transcription-1 and -3; YY1: YIN-YANG-1 transcription factor.