Lipid remodeling is crucial for hypoxic tolerance in animals, whilst little known about the hypoxia-induced lipid dynamics plants. Here we performed a mass spectrometry-based analysis to survey profiles of Arabidopsis rosettes under various conditions. We observed that hypoxia caused significant increase total amounts phosphatidylserine, phosphatidic acid and oxidized lipids, but decrease phosphatidylcholine (PC) phosphatidylethanolamine (PE). Particularly, gains polyunsaturated species PC,...

Arabidopsis thaliana plants that lack ceramide kinase, encoded by ACCELERATED CELL DEATH5 (ACD5), display spontaneous programmed cell death late in development and accumulate substrates of ACD5. Here, we compared accumulation kinetics, defense responses, ultrastructural features, sites reactive oxygen species (ROS) production wild-type acd5 during and/or Botrytis cinerea infection. Quantitative sphingolipid profiling indicated paralleled the appearance death, it was accompanied autophagy...

With global warming and climate change, abiotic stresses often simultaneously occur. Combined salt heat stress was a common phenomenon that severe, particularly in arid/semi-arid lands. We aimed to reveal the systematic responsive mechanisms of tomato genotypes with different salt/heat susceptibilities combined stress. Morphological physiological responses salt-tolerant/sensitive heat-tolerant/sensitive tomatoes at control, heat, were investigated. Based on leaf F

Ceramidases hydrolyze ceramide into sphingosine and fatty acids. In mammals, ceramidases function as key regulators of sphingolipid homeostasis, but little is known about their roles in plants. Here we characterize the Arabidopsis ceramidase AtACER, a homolog human alkaline ceramidases. The acer-1 T-DNA insertion mutant has pleiotropic phenotypes, including reduction leaf size, dwarfing an irregular wax layer, compared with wild-type Quantitative profiling showed that mutants artificial...

Summary In A rabidopsis thaliana , acyl‐CoA‐binding proteins ( ACBP s) are encoded by a family of six genes 1 to 6 ), and essential for diverse cellular activities. Recent investigations suggest that the membrane‐anchored s involved in oxygen sensing sequestration group VII ethylene‐responsive factors under normoxia. Here, we demonstrate involvement 3 hypoxic tolerance. transcription was remarkably induced following submergence both dark DS ) light LS conditions. ‐overexpressors 3‐ OE showed...

Abstract Serine palmitoyltransferase (SPT), a pyridoxyl-5′-phosphate-dependent enzyme, catalyzes the first and rate-limiting step in sphingolipid biosynthesis. In humans yeast, orosomucoid proteins (ORMs) negatively regulate SPT thus play an important role maintaining levels. Despite importance of sphingoid intermediates as bioactive molecules, regulation biosynthesis through is not well understood plants. Here, we identified characterized Arabidopsis thaliana ORMs, ORM1 ORM2. Loss function...

Sphingolipids have key functions in plant membrane structure and signaling. Perturbations of sphingolipid metabolism often induce cell death salicylic acid (SA) accumulation; SA accumulation, turn, promotes further death. However, the underlying molecular mechanisms remain unclear. Here, we show that Arabidopsis thaliana lipase-like protein ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) its partner PHYTOALEXIN DEFICIENT 4 (PAD4) participate associated The accelerated 5 (acd5) mutants accumulate...

Ceramidases hydrolyze ceramide into sphingosine and fatty acids and, although ceramidases function as key regulators of sphingolipid homeostasis in mammals, their roles plants remain largely unknown. Here, we characterized the Arabidopsis thaliana ceramidase AtNCER1, a homolog human neutral ceramidase. AtNCER1 localizes predominantly on endoplasmic reticulum. The ncer1 T-DNA insertion mutants had no visible phenotype, but accumulated hydroxyceramides, showed increased sensitivity to...

Waterlogging and heavy mental (e.g., cadmium) stress are two primary threats to crop growth. The combination of abiotic stresses was common frequent, especially in the field condition. Even though effects individual waterlogging cadmium on tomato plants have been widely investigated, response tomatoes under combined remains unclear. This study aimed clarify compare physiological, biochemical characteristics plant growth genotypes stress. Two ('MIX-002' 'LA4440') were treated control,...

Sphingolipids are cell membrane components and signaling molecules that induce endoplasmic reticulum (ER) stress responses, but the underlying mechanism is unknown. Orosomucoid proteins (ORMs) negatively regulate serine palmitoyltransferase activity, thus helping maintain proper sphingolipid levels in humans, yeast, plants. In this report, we explored roles of ORMs regulating ER Arabidopsis thaliana. Loss ORM1 ORM2 function caused constitutive activation unfolded protein response (UPR), as...

Sphingolipids have essential structural and bioactive functions in membranes signaling. However, how plants regulate sphingolipid biosynthesis the response to stress remains unclear. Here, we reveal that plant hormone ethylene can modulate synthesis. The fungal toxin Fumonisin B1 (FB1) inhibits activity of ceramide synthases, perturbing homeostasis thus inducing cell death. We used FB1 test role signaling synthesis Arabidopsis thaliana. etr1-1 ein2 mutants, which disrupted signaling,...

Sphingolipids act as structural components of cellular membranes and signals in a variety plant developmental processes defense responses, including programmed cell death. Recent studies have uncovered an interplay between abiotic or biotic stress In previous study, we characterized Arabidopsis (

Waterlogging stress caused by concentrated and heavy rainfall has become an increasingly popular abiotic stress, especially for tomato production. The aim is to clarify the leaf physiological biochemical responses as well flower fruit set of plants at reproductive stage under waterlogging stress. Six genotypes including 'MIX-002', 'LA4440', 'Fenbeibei', 'Hezuo 908', 'Jinzhu' 'Ruifen 882' anthesis were treated control We found that plant height, stem diameter, inflorescences number, single...

SUMMARY Sphingolipids, a class of bioactive lipids, play critical role in signal transduction. Ceramides, which are central components sphingolipid metabolism, involved plant development and defense. However, the mechanistic link between ceramides downstream signaling remains unclear. Here, mutation alkaline ceramidase ceramide kinase mutant acd5 resulted spontaneous programmed cell death early was accompanied by accumulation, while other types sphingolipids, such as long chain base,...

Plant sphingolipids are important membrane components and bioactive molecules in development defense responses. However, the function of plant defense, especially against herbivores, is not fully understood. Here, we report that Spodoptera exigua feeding affects sphingolipid metabolism Arabidopsis, resulting increased levels sphingoid long-chain bases, ceramides, hydroxyceramides. Insect-induced ceramide hydroxyceramide accumulation dependent on jasmonate signaling pathway. Loss Arabidopsis...

With global climate change, the frequency and intensity of waterlogging events are increasing due to frequent heavy precipitation. Little is known however about response plants repeated stress events. The aim clarify physiological regulation mechanisms tomato under stress, whether Trichoderma harzianum can alleviate injury. We identified two genotypes tomato, 'MIX-002' 'LA4440', as tolerant sensitive genotypes, respectively, based on plant biomass accumulation. were subjected a priming...

The deterioration in fruit quality of commercial tomatoes is a major concern modern tomato breeding. However, the metabolism and genetics are poorly understood. Here, we performed transgenic molecular biology experiments to reveal that phytoene synthase 1 (SlPSY1) responsible for accumulation an important flavor chemical, 6-methyl-5-hepten-2-one (MHO). To dissect function SlPSY1 regulating quality, generated analyzed dataset encompassing over 2 000 compounds detected by GC-MS LC-MS/MS along...

The phytohormone salicylic acid (SA) affects plant development and defense responses. Recent studies revealed that SA also participates in the regulation of sphingolipid metabolism, but details this remain to beexplored. Here, we use silico Flux Balance Analysis (FBA) with published microarray data construct a whole-cell simulation model, including 23 pathways, 259 reactions, 172 metabolites, predict alterations flux major species after treatment exogenous SA. This model predicts significant...

Sphingolipids are structural components of the lipid bilayer that acts as signaling molecules in many cellular processes, including cell death. Ceramides, key intermediates sphingolipid metabolism, phosphorylated by ceramide kinase ACCELERATED CELL DEATH5 (ACD5). The loss ACD5 function leads to accumulation and spontaneous Here, we report jasmonate (JA) pathway is activated Arabidopsis (Arabidopsis thaliana) acd5 mutant methyl JA treatment accelerates death acd5. Moreover, double mutants...

Cellular membranes contain many lipids, some of which, such as sphingolipids, have important structural and signaling functions. The common sphingolipid glucosylceramide (GlcCer) is present in plants, fungi, animals. As a major plant sphingolipid, GlcCer involved the formation lipid microdomains, regulation key for acclimation to stress. Although biosynthetic pathway has been elucidated, little known about catabolism, GlcCer-degrading enzyme (glucosylceramidase (GCD)) yet be identified....

Cellular membranes contain many lipids, some of which, such as sphingolipids, have important structural and signaling functions. The common sphingolipid glucosylceramide (GlcCer) is present in plants, fungi, animals. As a major plant sphingolipid, GlcCer involved the formation lipid microdomains, regulation key for acclimation to stress. Although biosynthetic pathway has been elucidated, little known about catabolism, GlcCer-degrading enzyme (glucosylceramidase (GCD)) yet be identified....

Abstract Sphingolipids are membrane lipids and play critical roles in signal transduction. Ceramides central components of sphingolipid metabolism that involved cell death. However, the mechanism ceramides regulating death plants remains unclear. Here, we found accumulated mitochondria accelerated 5 mutant (acd5), expression mitochondrion-localized ceramide kinase (ACD5) suppressed mitochondrial accumulation acd5 phenotype. Using immuno-electron microscopy, observed hyperaccumulation acer...

Fungal glucosylceramide plays important role in cell division, hyphal formation and growth, spore germination the modulation of virulence has recently been considered as target for small molecule inhibitors. In this study, we characterized CgGCS, a protein encoding synthase (GCS) Colleotrichum gloeosporioides. Disruption CgGCS resulted severe reduction mycelial growth defects conidiogenesis. Sphingolipid profile analysis revealed large decreases production mutant strains. Pathogenicity...

Plant activators are chemicals that induce plant defense responses to various pathogens. Here, we reported a new potential activator, 6-(methoxymethyl)-2-[5-(trifluoromethyl)-2-pyridyl] pyrimidin-4-ol, named PPA2 (pyrimidin-type activator 2). Unlike the traditional commercial benzothiadiazole S-methyl ester (BTH), was fully soluble in water, and it did not inhibit growth or root system development rice (Oryza sativa). pretreatment significantly increased resistance against bacterial...