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47  structures 8962  species 0  interactions 24535  sequences 309  architectures

Clan: GIY-YIG (CL0418)


GIY-YIG endonuclease superfamily Add an annotation

Based on the analysis of genomic distribution, patterns of domain fusions and phylogenetic considerations for individual families, an evolutionary scenario is proposed that explains the emergence and development of the major branches of the GIY-YIG superfamily that links the Slx-type with the UvrC-like endonucleases. Most families appear to target DNA. The GIY-YIG domain has been quite successful in forming monomeric nucleases that utilise additional domains to recognise its DNA targets; this collection of domains can range from extremely simple DNA-binding elements (as in the case of I-TevI) to modules with independent enzymatic activities (as in the case of UvrC or the Penelope elements) [1].

This clan contains 7 families and the total number of domains in the clan is 24535. The clan was built by RD Finn and P Coggill.

Literature references

  1. Dunin-Horkawicz S, Feder M, Bujnicki JM; , BMC Genomics. 2006;7:98.: Phylogenomic analysis of the GIY-YIG nuclease superfamily. PUBMED:16646971 EPMC:16646971


This clan contains the following 7 member families:

DUF123 GIY-YIG GIY_YIG_domain MUG113 RE_Eco29kI SegE_GIY-YIG T5orf172

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
GIY-YIG (PF01541) 19453 (79.3%) View
T5orf172 (PF10544) 3132 (12.8%) View
MUG113 (PF13455) 910 (3.7%) View
DUF123 (PF01986) 467 (1.9%) View
GIY_YIG_domain (PF19239) 308 (1.3%) View
RE_Eco29kI (PF09517) 152 (0.6%) View
SegE_GIY-YIG (PF19835) 113 (0.5%) View
Total: 7 Total: 24535 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...