PfTERT localizes in a discrete nuclear region in certain blood stream stages. (B) The 48 h time course in blood stages, during which parasites develop inside an erythrocyte. PfTERT (green) was detected by IF using the rabbit anti-peptide antibody; nuclear DNA was stained with DAPI (blue). (C) Peptide competition assay. The specificity of PfTERT serum was determined by IF after pre-incubating the antibodies with increasing concentrations of a specific (C-PfTERT) or an unspecific peptide. Detection of anti-PfTERT antibodies and staining of DNA was performed as in (B). Studies using rabbit a-PfTERT-peptide revealed no staining in the first 12 h (ring stages). When the parasite matures into trophozoite stage, however, a clear pattern was observed: a single dot within a region of the nucleus. During schizogony, the number of PfTERT foci increased proportionally to the number of nuclei. When schizonts become fully mature (48 h) and merozoites are released into the blood stream, PfTERT was no longer detectable. When the above IF assay was undertaken in the presence of competing epitopes, the PfTERT signal disappeared with increasing concentrations of the C-terminal PfTERT peptide (C-PfTERT); in contrast, when an unspecifc
peptide was used as competitor, the PfTERT signal intensity remained unchanged
Figueiredo LM, Rocha EP, Mancio-Silva L, Prevost C, Hernandez-Verdun D, Scherf A. The unusually large Plasmodium telomerase reverse-transcriptase localizes in a discrete compartment associated with the nucleolus. Nucleic Acids Res. 2005 33:1111-22.