Fig. 5: Monitoring the source of fatty acids in TgLIPIN-ikD. | Nature Communications

Fig. 5: Monitoring the source of fatty acids in TgLIPIN-ikD.

From: Toxoplasma LIPIN is essential in channeling host lipid fluxes through membrane biogenesis and lipid storage

Fig. 5

a–c Schematic for the experimental procedure of stable isotope labeling to determine the origin of fatty acids in TgLIPIN-ikD; a Parasite FASII derived FAs were determined by the addition of U-13C-glucose (Glc) to the culture medium (1% FBS, no glucose, +/−ATc) at the time of parasite infection to the host. b FAs scavenged from the external environment (medium) was determined by the addition of 31d-palmitic acid (31d-C16:0) to the parasite culture medium (high glucose, 1% FBS). c Host cell-derived FAs were determined by growing host cells in the presence of U-13C-glucose (no glucose, 10% FBS) to confluent in prior to the infection parasites with normal medium (glucose, 1% FBS, + /−ATc). d FASII activity in TgLIPIN-ikD as measured as % 13C-incorporation (n = 3, unpaired t test P values; ***P < 0.0005% FASII derived C14:0/C16:0/C18:0/C18:1 −ATc vs +ATc, **P < 0.007/*P < 0.04/***P < 0.0003). e Abundance of apicoplast FASII derived 13C labeled FFAs (n = 3, unpaired t test P values; *P < 0.02 of FASII derived FFA C18:1-ATc vs +ATc). f Abundance of apicoplast FASII derived 13C-labeled phospholipids (PLs, n = 4, unpaired t test P values; *P < 0.03 of FASII derived PL C18:0-ATc vs +ATc). g FA uptake of deuterated external environment-derived FAs (n = 4, unpaired t test P values; **P = 0.0034/***P < 0.00001/*P = 0.01 FA uptake from the external environment as d31C16:0/d31C18:0/d29C18:1 −ATc vs +ATc). h Relative abundance of deuterated external environment-derived (+ATc/−ATc) (n = 3). i The abundance of 13C-labeled fatty acids in the host cells (n = 4). j Host derived FAs measured as % 13C-incorporation (n = 3, unpaired t test P values; *P < 0.02 Host derived FA C18:1-ATc vs +ATc). k Abundance of host-derived 13C-labeled FFAs (n = 3, unpaired t test P values; *P < 0.05 Host derived FA C16:0/16:1/18:1−ATc vs +ATc). l Abundance of host-derived 13C labeled PL (n = 3, unpaired t test P values; *P < 0.023 Host derived PL C18:0−ATc vs +ATc) and m TAG levels (n = 3, unpaired t test P values; ***P < 0.0001 Host-derived TAG C16:0/18:1−ATc vs +ATc). Data are all presented as mean values + /− SEM.

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