Table 1.

Mammalian Tudor domain-containing proteins as histone methylation ‘readers’, and their biological functions

Protein	Domain architecture	Tudor ligand	Kd (μM)	Biological functions	Ref.
JMJD2A		H3K4me3	~0.5	H3K9me3 and H3K36me3- specific demethylase; transcriptional regulation and regulator of DNA damage response	28, 45, 48
		H4K20me3	~0.4
		H4K20me2	~2
53BP1		H4K20me2	20~50	substrate of ATM; promote non-homologous end joining DNA repair	29, 44
SGF29		H3K4me3	1~4	component of SAGA complex; mediate transcriptional activation	30, 31
Spindlin1		H3K4me3	~0.8	nucleolar protein; promote rRNA transcription	32, 33
UHRF1		H3K9me3 by Tudor	1~3	partner of DNMT1; maintain the level of DNA methylation during DNA replication	35, 37, 66, 88, 89
		H3 N-terminus& K9me3 byTudor-PHD	~0.4
PHF1		H3K36me3	5~50#	accessory component of PRC2 complex; promote transcriptional repression	38, 39, 40
PHF19		H3K36me3	6~35#	accessory component of PRC2 complex; promote transcriptional repression	38, 40, 41, 42
LBR		H4K20me2	N.D.	inner nuclear membrane protein; promote formation of nuclear peripheral heterochromatin	84
TDRD3		H4R3me2a; H3R17me2a; H3R2me2a	>500	transcriptional coactivator and interacts with CARM1 and PRMT1	105, 109

Abbreviations: Kd, dissociation constant; N.D., not defined; ATM, Ataxia telangiectasia mutated; PRC2, polycomb repressive complex 2 Modifications: me1, monomethylation; me2, dimethylation; me3, trimethylation; me2a, asymmetric dimethylation.

Protein domains: UBA, ubiquitin-associated domain; JmjN, jumonji N domain; JmjC, jumonji C domain; PHD, plant homeodomain; BRCT, BRCA1 C terminus domain; UBL, ubiquitin-like domain; SRA, SET and RING finger associated domain; RING, really interesting new gene finger domain.

^#for PHF1 or PHF19 binding to H3K36me3 peptides, a Kd of 5~6 μM was obtained at 4 degree in a buffer of 100 mM NaCl and 20 mM Tris-HCl pH 7.5, and a higher Kd of 35–50 μM obtained at 25 degree in a buffer of 150 mM NaCl and 20 mM Tris, pH 6.8–7.5.