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213  structures 432  species 8  interactions 13145  sequences 846  architectures

Clan: PSI (CL0630)


Plexin fold superfamily Add an annotation

This superfamily includes a disulphide rich domain found in Plexins, semaphorins and some integrin protein. According to SCOP the common core is alpha+beta with two conserved disulfides.

This clan contains 3 families and the total number of domains in the clan is 13145. The clan was built by A Bateman.


This clan contains the following 3 member families:

PSI PSI_integrin Trefoil

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
PSI (PF01437) 8714 (66.3%) View
Trefoil (PF00088) 2530 (19.2%) View
PSI_integrin (PF17205) 1901 (14.5%) View
Total: 3 Total: 13145 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...



There are 8 interactions for this clan. More...

Interacting families
Glyco_hydro_31 Trefoil
PSI Ig_2
Sema PSI
Trefoil Glyco_hydro_31


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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