title: Protein profiling of mefloquine resistantPlasmodium falciparumusing mass spectrometry-based proteomics.
abstract: Malaria is a mosquito borne infectious disease caused by protozoa of genusPlasmodium. There are five species ofPlasmodiumthat are found to infect humans.Plasmodium falciparumcan cause severe malaria leading to higher morbidity and mortality of malaria than the other four species. Antimalarial resistance is the major obstacle to control malaria. Mefloquine was used in combination with Artesunate for uncomplicatedP. falciparumin South East Asia and it has developed and established mefloquine resistance in this region. Here, gel-enhanced liquid chromatography/tandem mass spectrometry (GeLC-MS/MS)-based proteomics and label-free quantification were used to explore the protein profiles of mefloquine-sensitive and -induced resistantP. falciparum. A ThaiP. falciparumisolate (S066) was used as a model in this research. Our data revealed for the first time that 69 proteins exhibited at least 2-fold differences in their expression levels between the two parasite lines. Of these, 36 were up-regulated and 33 were down-regulated in the mefloquine-resistant line compared with the mefloquine-sensitive line. These findings are consistent with those of past studies, where the multidrug resistance protein Pgh1 showed an up-regulation pattern consistent with that expected from its average 3-copy pfmdr1 gene number. Pgh1 and eight other up-regulated proteins (i.e., histo-aspartyl protease protein, exportin 1, eukaryotic translation initiation factor 3 subunit 8, peptidyl-prolyl cis-trans isomerase, serine rich protein homologue, exported protein 1, ATP synthase beta chain and phospholipid scramblase 1) were further validated for their expression levels using reverse transcriptase quantitative real-time PCR. The data support the up-regulation status in the mefloquine-resistant parasite line of all the candidate genes referred to above. Therefore, GeLC-MS/MS-based proteomics combined with label-free quantification is a reliable approach for exploring mefloquine resistance biomarkers inP. falciparum. Identification of these proteins leads to better understanding of mefloquine resistant mechanisms in malaria parasites.
authors: Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
authors: Onrapak
authors: O
authors: Reamtong
authors: Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
authors: Krongkan
authors: K
authors: Srimuang
authors: Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
authors: Naowarat
authors: N
authors: Saralamba
authors: Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors: Polkit
authors: P
authors: Sangvanich
authors: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom.
authors: Nicholas P J
authors: NP
authors: Day
authors: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom.
authors: Nicholas J
authors: NJ
authors: White
authors: Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
authors: Mallika
authors: M
authors: Imwong
keywords: GeLC–MS/MS label-free quantification; Mefloquine; Pgh1; Plasmodium falciparum; Proteomics