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0  structures 22  species 0  interactions 2585  sequences 40  architectures

Clan: VSA (CL0656)


Variant surface antigens Add an annotation

Members of this clan belong to variant surface antigens (VSA). They are gene products encoded by multi-copy gene families. Four of the largest multi-copy gene families found in the genome of P. falciparum are designated as var, rif (repetitive interspersed family), stevor (subtelomeric variable open reading frame) and pfmc-2tm (P. falciparum Maurer's clefts 2 transmembrane). They code for variable proteins termed PfEMP1 (P. falciparum erythrocyte membrane protein 1), RIFIN, STEVOR and PfMC-2TM, respectively. All small VSA proteins contain a signal peptide and a PEXEL/HT motif. This characteristic as well as their large number and hypervariability support their suggested role in antigenic variation. Antigenic variation and sequestration are strategies used by the malaria parasite P. falciparum to evade antibody mediated immune recognition and splenic clearance [1].

This clan contains 2 families and the total number of domains in the clan is 2585. The clan was built by S El-Gebali.

Literature references

  1. Bachmann A, Scholz JA, Janssen M, Klinkert MQ, Tannich E, Bruchhaus I, Petter M;, Malar J. 2015;14:274.: A comparative study of the localization and membrane topology of members of the RIFIN, STEVOR and PfMC-2TM protein families in Plasmodium falciparum-infected erythrocytes. PUBMED:26173856 EPMC:26173856


This clan contains the following 2 member families:

RIFIN Stevor

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
RIFIN (PF02009) 2070 (80.1%) View
Stevor (PF17410) 515 (19.9%) View
Total: 2 Total: 2585 Clan alignment

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Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

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This tree shows the occurrence of the domains in this clan across different species. More...