title: Ca(2+) monitoring in Plasmodium falciparum using the yellow cameleon-Nano biosensor.
abstract: Calcium (Ca(2+))-mediated signaling is a conserved mechanism in eukaryotes, including the human malaria parasite, Plasmodium falciparum. Due to its small size (<10 μm) measurement of intracellular Ca(2+) in Plasmodium is technically challenging, and thus Ca(2+) regulation in this human pathogen is not well understood. Here we analyze Ca(2+) homeostasis via a new approach using transgenic P. falciparum expressing the Ca(2+) sensor yellow cameleon (YC)-Nano. We found that cytosolic Ca(2+) concentration is maintained at low levels only during the intraerythrocytic trophozoite stage (30 nM), and is increased in the other blood stages (>300 nM). We determined that the mammalian SERCA inhibitor thapsigargin and antimalarial dihydroartemisinin did not perturb SERCA activity. The change of the cytosolic Ca(2+) level in P. falciparum was additionally detectable by flow cytometry. Thus, we propose that the developed YC-Nano-based system is useful to study Ca(2+) signaling in P. falciparum and is applicable for drug screening.
authors.affiliation: Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.|Nepal Academy of Science and Technology (NAST), GPO Box: 3323, Khumaltar, Lalitpur, Nepal.
authors.forename: Kishor
authors.initials: K
authors.lastname: Pandey
authors.affiliation: Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.|School of Biological Science, Nanyang Technological University, Singapore.|Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.
authors.forename: Pedro E
authors.initials: PE
authors.lastname: Ferreira
authors.affiliation: Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Takeharu
authors.initials: T
authors.lastname: Nagai
authors.affiliation: Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Kaneko
authors.affiliation: Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Yahata
mesh_terms: D037621:Artemisinins / Q000494:pharmacology; D015374:Biosensing Techniques / Q000379:methods*; D002118:Calcium / Q000032:analysis* / Q000378:metabolism; D020013:Calcium Signaling; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003600:Cytosol / Q000737:chemistry; D004912:Erythrocytes / Q000469:parasitology*; D006706:Homeostasis; D006801:Humans; D030781:Organisms, Genetically Modified; D010963:Plasmodium falciparum / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism; D019284:Thapsigargin / Q000494:pharmacology; D053058:Trophozoites / Q000737:chemistry
chemical_list: D037621:Artemisinins; D002135:Calcium-Binding Proteins; C495639:yellow cameleon; D019284:Thapsigargin; C039060:artenimol; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D002118:Calcium