Heat tolerance as a function of membrane lipid remodeling in the major US oilseed crops (soybean and peanut)

Abstract Climate change-induced global warming threatens the survival of key ecosystems including shallow water coral reefs. Elevated temperatures can disrupt the normal physiological functioning of photosynthetic organisms by altering the fluidity and permeability of chloroplast membranes that is defined and regulated by their lipid composition. Since the habitat-forming reef corals rely on the obligatory symbiosis with dinoflagellates of the family Symbiodiniaceae, their heat stress response can be expected to be strongly influenced by the symbiont's lipid metabolism. However, in contrast to the steady increase in the knowledge of the functioning of coral symbionts at the genomic and transcriptomic level, the understanding of their membrane lipid composition and regulation in response to temperature stress is lagging behind. We have utilised mass spectrometry-based lipidomic analyses to identify the key polar lipids that form the biological membranes of reef coral symbionts, comparing the thermotolerant species Durusdinium trenchii with the thermosensitive taxon Cladocopium C3, both hosted by Acropora valida. Our results indicate that the superior thermotolerance D. trenchii inside the host corals could be achieved through (1) the amount and saturation of sulfoquinovosyldiacylglycerols, in particular through putative photosystem II interactions, (2) the increased digalactosyldiacylglycerol to monogalactosyldiacylglycerol ratio with the potential to stabilise thylakoid membranes and integrated proteins, and (3) the chaperone-like function of lyso-lipids. Thereby, our study provides novel insights into the heat tolerance of coral symbionts, contributing to the understanding of the potential of coral reef ecosystems to respond and adjust to heat stress events that are becoming more frequent due to climate change. Finally, our identification of multiple mechanisms of heat tolerance in Symbiodiniaceae furthers the knowledge of the general stress physiology of photosynthetic organisms.

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Increased expression of fatty acid and ABC transporters enhances seed oil production in camelina

Biotechnology for Biofuels ◽

10.1186/s13068-021-01899-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Guangqin Cai ◽

Geliang Wang ◽

Sang-Chul Kim ◽

Jianwu Li ◽

Yongming Zhou ◽

...

Keyword(s):

Fatty Acid ◽

Seed Oil ◽

Oil Production ◽

Membrane Lipid ◽

Seed Oil Content ◽

Seed Length ◽

Oilseed Crops ◽

Camelina Oil ◽

Atp Binding Cassette Transporter ◽

Lipid Transporters

Abstract Background Lipid transporters play an essential role in lipid delivery and distribution, but their influence on seed oil production in oilseed crops is not well studied. Results Here, we examined the effect of two lipid transporters, FAX1 (fatty acid export1) and ABCA9 (ATP-binding cassette transporter subfamily A9) on oil production and lipid metabolism in the oilseed plant Camelina sativa. Overexpression (OE) of FAX1 and ABCA9 increased seed weight and size, with FAX1-OEs and ABCA9-OEs increasing seed length and width, respectively, whereas FAX1/ABCA9-OEs increasing both. FAX1-OE and ABCA9-OE displayed additive effects on seed oil content and seed yield. Also, OE of FAX1 and ABCA9 affected membrane lipid composition in developing pods, especially on phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The expression of some genes involved in seed oil synthesis, such as DGAT2, PDAT1, and LEC1, was increased in developing seeds of FAX1- and/or ABCA9-OEs. Conclusion These results indicate that increased expression of FAX1 and ABCA9 can potentially be applied to improving camelina oil production.

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Sitosterol-mediated Antioxidant Regulation to Enhance Heat Tolerance in Creeping Bentgrass

Journal of the American Society for Horticultural Science ◽

10.21273/jashs05107-21 ◽

2022 ◽

Vol 147 (1) ◽

pp. 18-24

Author(s):

Stephanie Rossi ◽

Bingru Huang

Keyword(s):

Heat Stress ◽

Leaf Senescence ◽

Heat Tolerance ◽

Foliar Application ◽

Creeping Bentgrass ◽

Membrane Lipid ◽

Membrane Stability ◽

Turf Quality ◽

Mda Content ◽

Plant Metabolite

Heat stress symptoms in cool-season plants are characterized by loss of chlorophyll (Chl) and membrane stability, as well as oxidative damage. The objectives of this study were to determine whether foliar application of β-sitosterol, a naturally occurring plant metabolite, may promote heat tolerance by suppressing heat-induced leaf senescence as indicated by the maintenance of healthy turf quality (TQ), and Chl and membrane stability; and to determine its roles in regulating antioxidant metabolism in creeping bentgrass (Agrostis stolonifera). ‘Penncross’ plants were exposed to heat stress (35/30 °C day/night) optimal temperature conditions (nonstressed control, 22/17 °C day/night) for a duration of 28 days in environment-controlled growth chambers. Plants were foliar-treated with β-sitosterol (400 µM) or water only (untreated control) before heat stress, and at 7-day intervals through 28 days of heat stress. Plants treated with β-sitosterol had significantly greater TQ and Chl content, and significantly less electrolyte leakage (EL) than untreated controls at 21 and 28 days of heat stress. Application of β-sitosterol reduced malondialdehyde (MDA) content significantly at 21 and 28 days of heat stress, and promoted the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) from 14 through 28 days of heat stress. β-Sitosterol effectively improved heat tolerance through suppression of leaf senescence in creeping bentgrass exposed to heat stress in association with the alleviation of membrane lipid peroxidation and activation of the enzymatic antioxidant system.

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Increased Expression of Fatty Acid and ABC Transporters Enhances Seed Oil Production in Camelina

10.21203/rs.3.rs-100742/v1 ◽

2020 ◽

Author(s):

Guangqin Cai ◽

Geliang Wang ◽

Sang-Chul Kim ◽

Jianwu Li ◽

Yongming Zhou ◽

...

Keyword(s):

Fatty Acid ◽

Seed Oil ◽

Oil Production ◽

Membrane Lipid ◽

Seed Oil Content ◽

Seed Length ◽

Oilseed Crops ◽

Camelina Oil ◽

Atp Binding Cassette Transporter ◽

Lipid Transporters

Abstract Background: Lipid transporters play an essential role in lipid delivery and distribution, but their influence on seed oil production in oilseed crops is not well studied. Results: Here we examined the effect of two lipid transporters, FAX1 (fatty acid export1) and ABCA9 (ATP-binding cassette transporter subfamily A9) on oil production and lipid metabolism in the oilseed plant Camelina sativa. Overexpression (OE) of FAX1 and ABCA9 increased seed weight and size, with FAX1-OEs and ABCA9-OEs increasing seed length and width, respectively, whereas FAX1/ABCA9-OEs increasing both. FAX1-OE and ABCA9-OE displayed additive effects on seed oil content and seed yield. Also, OE of FAX1 and ABCA9 affected membrane lipid composition in developing siliques, especially on phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The expression of some genes involved in seed oil synthesis was increased in developing seeds of FAX1- and/or ABCA9-OEs. Conclusions: These results indicate that increased expression of FAX1 and ABCA9 can potentially be applied to improving camelina oil production.

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Membrane Lipid Composition and Heat Tolerance in Cool-season Turfgrasses, including a Hybrid Bluegrass

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.134.5.511 ◽

2009 ◽

Vol 134 (5) ◽

pp. 511-520 ◽

Cited By ~ 28

Author(s):

Kemin Su ◽

Dale J. Bremer ◽

Richard Jeannotte ◽

Ruth Welti ◽

Celeste Yang

Keyword(s):

Heat Tolerance ◽

Molecular Species ◽

Festuca Arundinacea ◽

Membrane Lipids ◽

Poa Pratensis ◽

Kentucky Bluegrass ◽

Membrane Lipid ◽

Cool Season ◽

Lipid Molecular Species ◽

Heat Tolerant

Cool-season turfgrasses may experience heat stress during summer. Hybrid bluegrasses (HBGs), crosses between kentucky bluegrass [KBG (Poa pratensis L.)] and native texas bluegrass (Poa arachnifera Torr.), have improved heat tolerance but the mechanisms of heat tolerance are poorly understood. Our objectives were to quantitatively profile membrane lipid molecular species in three cool-season turfgrasses exposed to optimal (22/15 °C, 14/10 h light/dark) and supra-optimal temperatures (35/25 °C and 40/30 °C, 14/10 h light/dark). Grasses included a low heat-tolerant tall fescue [TF (Festuca arundinacea Schreb. ‘Dynasty’)], a mid-heat–tolerant KBG (‘Apollo’), and a heat-tolerant HBG (‘Thermal Blue’). At high temperature, glycolipid digalactosyldiacylglycerol (DGDG) in HBG was 12% and 16% greater than in KBG and TF, respectively, and the ratio DGDG to monogalactosyldiacylglycerol was 19% and 44% greater in HBG than in KBG and TF, respectively. Greater heat tolerance in HBG and KBG was associated with higher contents of phosphatidylethanolamine and phosphatidylglycerol, and with reduced overall unsaturation compared with TF. Overall, 20 lipid molecular species were present in greater amounts and another 20 species in lesser amounts in HBG and KBG than in TF. Results suggest 40 membrane lipid molecules are potential biomarkers for heat tolerance and that compositional changes in membrane lipids in response to heat contribute to differences in heat tolerance among cool-season grasses.

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Increased expression of fatty acid and ABC transporters enhances seed oil production in camelina

10.21203/rs.3.rs-100742/v2 ◽

2021 ◽

Author(s):

Guangqin Cai ◽

Geliang Wang ◽

Sang-Chul Kim ◽

Jianwu Li ◽

Yongming Zhou ◽

...

Keyword(s):

Fatty Acid ◽

Seed Oil ◽

Oil Production ◽

Membrane Lipid ◽

Seed Oil Content ◽

Seed Length ◽

Oilseed Crops ◽

Camelina Oil ◽

Atp Binding Cassette Transporter ◽

Lipid Transporters

Abstract Background: Lipid transporters play an essential role in lipid delivery and distribution, but their influence on seed oil production in oilseed crops is not well studied. Results: Here we examined the effect of two lipid transporters, FAX1 (fatty acid export1) and ABCA9 (ATP-binding cassette transporter subfamily A9) on oil production and lipid metabolism in the oilseed plant Camelina sativa. Overexpression (OE) of FAX1 and ABCA9 increased seed weight and size, with FAX1-OEs and ABCA9-OEs increasing seed length and width, respectively, whereas FAX1/ABCA9-OEs increasing both. FAX1-OE and ABCA9-OE displayed additive effects on seed oil content and seed yield. Also, OE of FAX1 and ABCA9 affected membrane lipid composition in developing pods, especially on phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The expression of some genes involved in seed oil synthesis, such as DGAT2, PDAT1, and LEC1, was increased in developing seeds of FAX1- and/or ABCA9-OEs. Conclusions: These results indicate that increased expression of FAX1 and ABCA9 can potentially be applied to improving camelina oil production.

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Inhibition of Platelet Aggregation by Ethanol in Vitro Shows Specificity for Aggregating Agent Used and Is Influenced by Platelet Lipid Composition

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657214 ◽

1982 ◽

Vol 48 (01) ◽

pp. 049-053 ◽

Cited By ~ 47

Author(s):

C G Fenn ◽

J M Littleton

Keyword(s):

Platelet Aggregation ◽

Lipid Composition ◽

Saturated Fatty Acids ◽

Calcium Ionophore ◽

Cholesterol Content ◽

Membrane Lipid ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

Increased Sensitivity

SummaryEthanol at physiologically tolerable concentrations inhibited platelet aggregation in vitro in a relatively specific way, which may be influenced by platelet membrane lipid composition. Aggregation to collagen, calcium ionophore A23187 and thrombin (low doses) were often markedly inhibited by ethanol, adrenaline and ADP responses were little affected, and aggregation to exogenous arachidonic acid was actually potentiated by ethanol. Aggregation to collagen, thrombin and A23187 was inhibited more by ethanol in platelets enriched with saturated fatty acids than in those enriched with unsaturated fats. Platelets enriched with cholesterol showed increased sensitivity to ADP, arachidonate and adrenaline but this increase in cholesterol content did not appear to influence the inhibition by ethanol of platelet responses. The results suggest that ethanol may inhibit aggregation by an effect on membrane fluidity and/or calcium mobilization resulting in decreased activity of a membrane-bound phospholipase.

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