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48  structures 2151  species 0  interactions 2779  sequences 55  architectures

Clan: AEP (CL0243)


Archaeo-eukaryotic primase Add an annotation

This clan includes the small subunit of 2 and eukaryotic DNA primase, and primase-helicase proteins from bacteriophages and plasmids. All known cellular life forms use primases to synthesis a short RNA primer which is extended during DNA replication by a polymerase. Bacterial DNA primase adopts a different fold to archaeal and eukaryotic primases and belongs to a different superfamily.

This clan contains 3 families and the total number of domains in the clan is 2779. The clan was built by J Mistry.

Literature references

  1. Iyer LM, Koonin EV, Leipe DD, Aravind L; , Nucleic Acids Res. 2005;33:3875-3896.: Origin and evolution of the archaeo-eukaryotic primase superfamily and related palm-domain proteins: structural insights and new members. PUBMED:16027112 EPMC:16027112


This clan contains the following 3 member families:

DNA_primase_S PPL4 Replicase

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
DNA_primase_S (PF01896) 2620 (94.3%) View
Replicase (PF03090) 129 (4.6%) View
PPL4 (PF18188) 30 (1.1%) View
Total: 3 Total: 2779 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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