Expression analyses of PfSec22 Antibodies were generated against a peptide sequence in the non-conserved region of PfSec22 and affinity purified as described in the ‘Materials and Methods’ section. (A) Immunoblot analysis of parasite extracts showing expression of endogenous PfSec22 in ring (R), trophozoite (T), and schizont (S) stage parasites. Absence of antibody reaction with the uninfected erythrocyte lysate (UE) indicates high specificity of the antibodies to the parasite protein. (B) Immunofluorescence microscopy of fixed cells using anti-PfSec22 antibodies and goat anti16 rabbit Alexa Fluor-555 secondary antibodies. An intense ring of PfSec22 fluorescence is visible in ring and trophozoite infected cells. Isolated foci of PfSec22 fluorescence (black arrow) are also detected in the host cell compartment in trophozoite-infected cells suggesting export of PfSec22 into the erythrocyte cytosol. Scale bar, 2μm Ayong L, Raghavan A, Schneider TG, Taraschi TF, Fidock DA, Chakrabarti D. The Longin domain regulates the steady-state dynamics of Sec22 in P. falciparum. Eukaryot Cell. 2009 8(9):1330-40