Immunofluorescence assays with variant-specific antibodies. An immunofluorescence assay (IFA) was performed using anti-PF3D7_0100300-His, anti-PF3D7_0600400-His, and anti-PF3D7_0937600-His IgG (1:50) as primary antibodies and anti-ATS IgG as the control. Specific staining of infected erythrocytes (IEs) is observed as punctuated fluorescence patterns over the IE surface using a secondary antibody labeled with Alexa 488 (green). The pre-immune sera of the immunized rats did not result in any surface reactivity with the IE. DAPI (5 mg/mL) staining of DNA in the nuclei is blue. The anti-ATS IgG and anti-PF3D7_0600400-His IgG stained IEs of both the trophozoite and schizont stages, the anti-PF3D7_0937600-His IgG only reacted with IEs of the trophozoite stage, while the anti-PF3D7_0100300-His IgG only reacted with IEs of the schizont stage.Zhang Y, Jiang N, Lu H, Hou N, Piao X, Cai P, Yin J, Wahlgren M, Chen Q. Proteomic analysis of Plasmodium falciparum schizonts reveals heparin-binding merozoite proteins. J Proteome Res. 2013 May 3;12(5):2185-93.

Monoallelic expression of var gene family is controlled by chromatin-associated RNase II (PFI0295c). a, Two-colour RNA-FISH of var transcripts in PfRNase II–FKBP-H3 and G1 clones. Red, UpsC-type C1 var probe (PFD0625c); green, upsA-type A1 var (PFF0020c). Co., co-localization; adj., adjacent; non-co., non-co-localization. Nuclear DNA was stained by DAPI (blue). Scale bar, 1 mm. b, Live-cell IFA using antisera to various PfEMP1s to detect co-expression of var genes in PfRNase II–FKBP H3 and G1 clones, respectively. The 3D7-G7 control expresses only one type of PfEMP1 (C1 var). Scale bar, 5 mm. c, PfRNase II is linked to the silent var-associated loci. Left: combined FISH/IFA assay using anti-PfRNase II antibody (IFA) with a FISHprobe (PFF0020c) that detected the upsA var expression site (RNA-FISH) in PfRNase II–FKBP clone H3. The same upsA var gene (DNA-FISH/IFA) was also analysed in ring-stage 3D7-G7 parasites.Zhang Q, Siegel TN, Martins RM, Wang F, Cao J, Gao Q, Cheng X, Jiang L, Hon CC, Scheidig-Benatar C, Sakamoto H, Turner L, Jensen AT, Claes A, Guizetti J, Malmquist NA, Scherf A. Exonuclease-mediated degradation of nascent RNA silences genes linked to severe malaria. Nature. 2014 Jun 29.