The total and mitochondrial lipidome of Artemia franciscana encysted embryos

Abstract

Encysted embryos (cysts) of the crustacean Artemia franciscana exhibit enormous tolerance to adverse conditions encompassing high doses of radiation, years of anoxia, desiccation and extreme salinity. So far, several mechanisms have been proposed to contribute to this extremophilia, however, none were sought in the lipid profile of the cysts. Here in, we used high resolution shotgun lipidomics suited for detailed quantitation and analysis of lipids in uncharacterized biological membranes and samples and assembled the total, mitochondrial and mitoplastic lipidome of Artemia franciscana cysts. Overall, we identified and quantitated 1098 lipid species dispersed among 22 different classes and subclasses. Regarding the mitochondrial lipidome, most lipid classes exhibited little differences from those reported in other animals, however, Artemia mitochondria harboured much less phosphatidylethanolamine, plasmenylethanolamines and ceramides than mitochondria of other species, some of which by two orders of magnitude. Alternatively, Artemia mitochondria exhibited much higher levels of phosphatidylglycerols and phosphatidylserines. The identification and quantitation of the total and mitochondrial lipidome of the cysts may help in the elucidation of actionable extremophilia-affording proteins, such as the 'late embryogenesis abundant' proteins, which are known to interact with lipid membranes.

Lipid Profile Changes During the Development of Artemia franciscana, From Cysts to the First Two Naupliar Stages

“…The mass spectrum of B2, in positive ion mode, revealed the main peaks at m/z 759.7, 773.7, 775.7, 789.7, and 811.6 corresponding to the protonated form of SM species and minor peaks at m/z 781.6, 795.7, and 797.6 corresponding to the sodiated form of other SM species (listed in Table 2). These data are an agreement of those obtained by Chen et al (2016) and Kojima et al (2010).…”

“…In the mass spectrum corresponding to PI, the main peaks are at m/z 857.6, 859.7, and 885.7 referable to different species (36:4, 36:3, and 38:4, respectively). The peaks at m/z 873.6 and 899.6 can be assigned to the plasmenyl-PI with chains 38:3 and 40:4, in agreement with literature (Chen et al, 2016). Minor peaks attributable to other PI species are also listed in Table 3.…”

“…Recently, the lipidome of cysts of A. franciscana has been studied in parallel with lipids of mitochondria isolated from cysts by high resolution shotgun lipidomics, aiming to gain basic knowledge in the elucidation of actionable extremophilia-affording proteins, such as on the late embryogenesis abundant proteins (LEA), which are known to interact with lipid membranes (Chen et al, 2016). LEA proteins are particularly protective of mitochondrial membranes against dehydration damage (Tolleter et al, 2010).…”

“…The study of Chen et al (2016) differentiates itself from previous lipid literature about Artemia; in effect, it represents the first lipidomic study on the Artemia eggs offering detailed information on lipid classes, on diversity within the lipid classes and on lipid proportions. Indeed, most of the previous analytical reports on lipids of Artemia are mainly related to nutritional analyses in aquaculture, given that the species is used as instant live food (Abatzopoulos et al, 2002).…”

Mitochondrial permeability transition pore: Back to the drawing board

“…Thus, the differential effect of bongkrekic acid on the same ANT but expressed in Artemia vs yeasts maybe due to the lipid environment in which the ANT is embedded. Indeed, mitochondria of Artemia franciscana harbor a very different lipidome than those found in other organisms, including yeasts (Chen et al, 2016). Thus, the lipidome composition of the inner mitochondrial membrane and how it is affected by known mPT modulatory mechanisms may hold the key to identifying mPT pore structure.…”