1. General structure of RIFINs and STEVORs
General structure of RIFINs and STEVORs. Protein domains are illustrated as green (signal peptide [SP]), gray (short hypervariable domain [V1] and hypervariable domain [V2]), red (transmembrane domains [TM]), black (PEXEL motif), blue (25-amino-acid sequence found only in RIFIN-A antigens), or orange/purple (semiconserved [SC] or conserved [C] domain).
General structure of RIFINs and STEVORs. Protein domains are illustrated as green (signal peptide [SP]), gray (short hypervariable domain [V1] and hypervariable domain [V2]), red (transmembrane domains [TM]), black (PEXEL motif), blue (25-amino-acid sequence found only in RIFIN-A antigens), or orange/purple (semiconserved [SC] or conserved [C] domain). RIFINs are encoded by 160 rif genes in the 3D7 reference genome, separated into two subtypes, RIFIN-A and RIFIN-B, depending on sequence, number of transmembrane domains, and subcellular localization. Thirty 3D7 genes encode STEVORs, which are structurally similar to RIFIN-Bs.
Albert E. Zhou et al. mSphere 2019; doi: /mSphere