PF3D7_0202000 knob-associated histidine-rich protein

VAR2CSA and CLAG9 localize predominantly to IRBC membranes of C4S-adherent parasites. Immunofluorescence and light micrographs (LM) of membrane-permeabilized (A and C) and intact (B and D) IRBCs of C4S-adherent FCR3 parasites, harvested at the late ring/early trophozoite stage, were stained by using rabbit anti-CLAG9 (A and B), rabbit anti-VAR2CSA (C and D), and mouse anti-KAHRP (control) antibodies at dilutions given in SI Materials and Methods. (E and F) Immunofluorescence and LM of permeabilized (E) and intact (F) C4S-adherent 3D7 IRBCs stained as above with anti-VAR2CSA antibodies. (G and H), Immunofluorescence and LM of permeabilized clag9−/− parasites stained with anti-VAR2CSA antibodies (G) and anti-CLAG9 antibodies (H). Anti-CLAG9 antibodies showed a strong staining of the IRBC membrane (A). A substantial level of CLAG9 is located at or in close proximity to the erythrocyte membrane. Nonpermeabilized IRBCs also showed onsiderable levels of staining of the erythrocyte surface with anti-CLAG9 antibodies (B). Anti-VAR2CSA antibodies also localized VAR2CSA on the erythrocyte membrane of both permeabilized and nonpermeabilized IRBCs of the C4S-adherent parasites (C and D)

Goel S, Valiyaveettil M, Achur RN, Goyal A, Mattei D, Salanti A, Trenholme KR, Gardiner DL, Gowda DC. Dual stage synthesis and crucial role of cytoadherence-linked asexual gene 9 in the surface expression of malaria parasite var proteins. Proc Natl Acad Sci U S A. 2010 107:16643-8.

Other associated proteins

PFID Formal Annotation
PF3D7_0935800 cytoadherence linked asexual protein 9
PF3D7_1200600 erythrocyte membrane protein 1, PfEMP1