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1344  structures 7959  species 0  interactions 167402  sequences 2848  architectures

Clan: Tudor (CL0049)


Tudor domain 'Royal family' Add an annotation

This clan covers the Tudor domain 'royal family' [1]. This includes chromo, MBT, PWWP and tudor domains. The chromo domain is a comprised of approximately 50 amino acid residues. There are usually one to three Chromo domains found in a single protein. In some chromo domain containing proteins, a second related chromo domain has been found and is referred to as the Chromo-shadow domain. The structure of the Chromo and Chromo-shadow domains reveal an OB-fold, a fold found in a variety of prokaryotic and eukaryotic nucleic acid binding proteins. More specifically,the chromo-domain structure reveals a three beta strands that are packed against an alpha helix. Interestingly, a similar structure is found in the archaeal chromatin proteins (7kDa DNA-binding domain). These are sequence neutral DNA binding proteins. The DNA binding in these archaeal proteins is mediated through the triple stranded beta sheet. These archaeal domains are though to represent an ancestral chromo domain. Homologs of the chromo domain have been found in fission yeast, ciliated protozoa and all animal species, but appear to be absent in eubacteria, budding yeast and plants [2]. The precise function of the chromo domain is unclear, but the chromo domain is thought to act as a targeting module for chromosomal proteins, although the chromosomal contexts and functional contexts being targeted vary. In all cases studies, the chromo domains are found in proteins that are involved in transcription regulation, positive and negative [2].

This clan contains 33 families and the total number of domains in the clan is 167402. The clan was built by RD Finn and A Bateman.

Literature references

  1. Maurer-Stroh S, Dickens NJ, Hughes-Davies L, Kouzarides T, Eisenhaber F, Ponting CP; , Trends Biochem Sci 2003;28:69-74.: The Tudor domain 'Royal Family': Tudor, plant Agenet, Chromo, PWWP and MBT domains. PUBMED:12575993 EPMC:12575993
  2. Eissenberg JC; , Gene 2001;275:19-29.: Molecular biology of the chromo domain: an ancient chromatin module comes of age. PUBMED:11574148 EPMC:11574148


This clan contains the following 33 member families:

53-BP1_Tudor 7kD_DNA_binding Agenet Chromo Chromo_2 Chromo_shadow Cul7 DUF1325 DUF4537 DUF4819 GEN1_C Hva1_TUDOR LBR_tudor LytTR MBT Mtf2_C ProQ_C PWWP Rad9_Rad53_bind RBB1NT SAWADEE SMN SNase TTD TUDOR Tudor-knot Tudor_1_RapA Tudor_2 Tudor_3 Tudor_4 Tudor_5 Tudor_FRX1 Tudor_RapA

External database links

Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
Chromo (PF00385) 31052 (18.5%) View
LytTR (PF04397) 23292 (13.9%) View
TUDOR (PF00567) 19247 (11.5%) View
PWWP (PF00855) 18826 (11.2%) View
MBT (PF02820) 17081 (10.2%) View
SNase (PF00565) 14812 (8.8%) View
Agenet (PF05641) 7453 (4.5%) View
Tudor-knot (PF11717) 6267 (3.7%) View
Tudor_2 (PF18104) 4702 (2.8%) View
Chromo_shadow (PF01393) 2768 (1.7%) View
SMN (PF06003) 2447 (1.5%) View
Hva1_TUDOR (PF11160) 2229 (1.3%) View
Tudor_FRX1 (PF18336) 1992 (1.2%) View
DUF1325 (PF07039) 1803 (1.1%) View
SAWADEE (PF16719) 1196 (0.7%) View
Cul7 (PF11515) 1160 (0.7%) View
Mtf2_C (PF14061) 1104 (0.7%) View
Pfam family Num. domains Alignment
Tudor_3 (PF18115) 1082 (0.6%) View
RBB1NT (PF08169) 1009 (0.6%) View
TTD (PF12148) 967 (0.6%) View
Tudor_1_RapA (PF18339) 784 (0.5%) View
Tudor_RapA (PF18337) 763 (0.5%) View
Tudor_5 (PF18359) 724 (0.4%) View
Tudor_4 (PF18358) 703 (0.4%) View
DUF4537 (PF15057) 682 (0.4%) View
GEN1_C (PF18380) 649 (0.4%) View
53-BP1_Tudor (PF09038) 604 (0.4%) View
DUF4819 (PF16090) 598 (0.4%) View
LBR_tudor (PF09465) 489 (0.3%) View
Chromo_2 (PF18704) 382 (0.2%) View
ProQ_C (PF17516) 345 (0.2%) View
Rad9_Rad53_bind (PF08605) 167 (0.1%) View
7kD_DNA_binding (PF02294) 23 (0.0%) View
Total: 33 Total: 167402 Clan alignment

Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.

Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.

Loading structure mapping...