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1362  structures 9012  species 0  interactions 29142  sequences 189  architectures

Clan: H2TH (CL0303)


Helix-two-turns-helix superfamily Add an annotation

This domain is thought to play a role in binding nucleic acids. It is DNA binding in nucleases and RNA-binding in ribosomal S13.

This clan contains 3 families and the total number of domains in the clan is 29142. The clan was built by A Bateman.


This clan contains the following 3 member families:

H2TH NFACT_N Ribosomal_S13

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
H2TH (PF06831) 12293 (42.2%) View
Ribosomal_S13 (PF00416) 12062 (41.4%) View
NFACT_N (PF05833) 4787 (16.4%) View
Total: 3 Total: 29142 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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