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580  structures 713  species 0  interactions 18802  sequences 267  architectures

Clan: C1q_TNF (CL0100)


C1q and TNF superfamily Add an annotation

The members of the C1q and TNF superfamily are involved in a diverse set of functions, which include: defense, inflammation, apoptosis, autoimmunity differentiation, organogenesis, hibernation and insulin-resistant obesity [1]. Both C1q and TNF domains form a compact jelly-roll beta- sandwich. The core of these structures are conserved between the two families and corresponds to the detectable sequence similarity. Proteins containing both of these domains, form trimers before they are active. However, the surfaces of the domains are quite different and this difference is thought to give rise to the function difference between the clan members[1].

This clan contains 7 families and the total number of domains in the clan is 18802. The clan was built by RD Finn.

Literature references

  1. Kishore U, Gaboriaud C, Waters P, Shrive AK, Greenhough TJ, Reid KB, Sim RB, Arlaud GJ; , Trends Immunol 2004;25:551-561.: C1q and tumor necrosis factor superfamily: modularity and versatility. PUBMED:15364058 EPMC:15364058


This clan contains the following 7 member families:

BclA_C C1q Chlam_vir DUF3845 Phage_tail_NK PRD1_P5_C TNF

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
C1q (PF00386) 13815 (73.5%) View
TNF (PF00229) 4671 (24.8%) View
BclA_C (PF18573) 270 (1.4%) View
Phage_tail_NK (PF16532) 31 (0.2%) View
DUF3845 (PF12956) 9 (0.0%) View
Chlam_vir (PF05475) 5 (0.0%) View
PRD1_P5_C (PF08949) 1 (0.0%) View
Total: 7 Total: 18802 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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