Expression and localization of Kae1api and Kae1cyto. Representative images of trophozoites are shown. Kae1api (top row) co-localizes with an apicoplast marker (acyl carrier protein, ACP), while Kae1cyto (second row) displays a diffuse signal throughout the parasite. Mitochondria and nuclei werevisualized with Mitotracker and DAPI-DNA stain, respectively. Lower row: Immuno-EM of Kae1api demonstrates localization to the apicoplast, bound by multiple membranes. Bar scale = 0.5 μm. Kae1api) displayed an elongated, punctate signal overlapping precisely with that of the apicoplasttargetedacyl carrier protein (ACP) in trophozoites and early schizonts . Both signals were detected in a compartment adjacent to, but distinct from the mitochondrion, consistent with apicoplast localization. Immuno-EM primarily detected Kae1api within structures bound by 3-4 membranes, further supporting that it is an apicoplast-targeted protein. In contrast, IFA detected a diffuse signal for Kae1cyto) throughout the parasite, suggesting a cytoplasmic location.Mallari JP, Oksman A, Vaupel B, Goldberg DE. Kinase-Associated Endopeptidase 1 (Kae1) Participates in an Atypical ribosome-Aassociated complex in the apicoplast of Plasmodium falciparum. J Biol Chem. 2014 Sep 9 [Epubahead of print]

Expression and localization of Kae1api interaction partners. Representative IFA images from RFA-tagged parasites are shown. IspG (top row), EF-Ts (middle row), and a putative RNA helicase (bottom row) co-localize with an apicoplast marker (ACP) and not with mitochondria. Mitochondria and nuclei were visualized with Mitotracker and DAPI-DNA stain, respectively. IFAstudies confirmed the apicoplast localization of all three proteins.Mallari JP, Oksman A, Vaupel B, Goldberg DE. Kinase-Associated Endopeptidase 1 (Kae1) Participates in an Atypical ribosome-Aassociated complex in the apicoplast of Plasmodium falciparum. J Biol Chem. 2014 Sep 9 [Epub ahead of print]