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270  structures 1577  species 0  interactions 16291  sequences 316  architectures

Clan: Triple_barrel (CL0662)


Triple barrel superfamily Add an annotation

Members of this superfamily adopt a triple barrel fold. This fold was first identified in the structure of the homodimer of RAP30 and RAP74. The two proteins form a single core structure composed of three interwoven beta barrels [1]. The central barrel is composed of beta strands from both heterodimer subunits. A similar fold has been observed in the heterodimer of TAF1 and TAF7 [2].

This clan contains 9 families and the total number of domains in the clan is 16291. The clan was built by A Bateman.

Literature references

  1. Gaiser F, Tan S, Richmond TJ;, J Mol Biol. 2000;302:1119-1127.: Novel dimerization fold of RAP30/RAP74 in human TFIIF at 1.7 A resolution. PUBMED:11183778 EPMC:11183778
  2. Wang H, Curran EC, Hinds TR, Wang EH, Zheng N;, Cell Res. 2014;24:1433-1444.: Crystal structure of a TAF1-TAF7 complex in human transcription factor IID reveals a promoter binding module. PUBMED:25412659 EPMC:25412659


This clan contains the following 9 member families:

DUF3591 RNA_pol_I_A49 RNA_pol_Rpc4 RNA_polI_A34 RNase_H2_suC RPC5 TAFII55_N TFIIF_beta_N Ydr279_N

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
DUF3591 (PF12157) 2539 (15.6%) View
RPC5 (PF04801) 2362 (14.5%) View
TAFII55_N (PF04658) 2016 (12.4%) View
RNA_pol_Rpc4 (PF05132) 1938 (11.9%) View
RNA_pol_I_A49 (PF06870) 1767 (10.8%) View
TFIIF_beta_N (PF17683) 1741 (10.7%) View
Ydr279_N (PF17745) 1475 (9.1%) View
RNase_H2_suC (PF08615) 1466 (9.0%) View
RNA_polI_A34 (PF08208) 987 (6.1%) View
Total: 9 Total: 16291 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.

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