Inner membrane complex proteomics reveals a palmitoylation regulation critical for intraerythrocytic development of malaria parasite
- Xiamen University, China
- Xiamen Center for Disease Control and Prevention, China
- Mahidol University, Thailand
Abstract
Malaria is caused by infection of the erythrocytes by the parasites Plasmodium. Inside the erythrocytes, the parasites multiply via schizogony, an unconventional cell division mode. The Inner Membrane Complex (IMC), an organelle located beneath the parasite plasma membrane, serving as the platform for protein anchorage, is essential for schizogony. So far, complete repertoire of IMC proteins and their localization determinants remain unclear. Here we used biotin ligase (TurboID)-based proximity labelling to compile the proteome of the schizont IMC of rodent malaria parasite Plasmodium yoelii. In total, 300 TurboID-interacting proteins were identified. 18 of 21 selected candidates were confirmed to localize in the IMC, indicating good reliability. In light of the existing palmitome of Plasmodium falciparum, 83 proteins of the P. yoelii IMC proteome are potentially palmitoylated. We further identified DHHC2 as the major resident palmitoyl-acyl-transferase of the IMC. Depletion of DHHC2 led to defective schizont segmentation and growth arrest both in vitro and in vivo. DHHC2 was found to palmitoylate two critical IMC proteins CDPK1 and GAP45 for their IMC localization. In summary, this study reports an inventory of new IMC proteins and demonstrates a central role of DHHC2 in governing IMC localization of proteins during the schizont development.
Data availability
The Mass spectrometry proteomic data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the data identifier PXD028193. All other relevant data in this study are submitted as supplementary source files.
Article and author information
Author details
Funding
National Natural Science Foundation of China (32170427,31970387,31872214)
- Jing Yuan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mouse experiments were performed by approved protocols (XMULAC20140004) by the Committee for Care and Use of Laboratory Animals of Xiamen University. The ICR mice (female, 5 to 6 weeks old) were purchased from the Animal Care Center of Xiamen University
Copyright
© 2022, Qian et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Inner membrane complex proteomics reveals a palmitoylation regulation critical for intraerythrocytic development of malaria parasite
eLife 11:e77447.
https://doi.org/10.7554/eLife.77447
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