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In human milk fat, palmitic acid (16:0) is esterified to the middle (sn-2 or β) position on the glycerol backbone and oleic acid (18:1) predominantly to the outer positions, giving the triacylglycerol (TG) a distinctive stereoisomeric structure that is believed to assist nutrient absorption in the infant gut. However, the fat used in most infant formulas is derived from plants, which preferentially esterify 16:0 to the outer positions. We have previously showed that the metabolism of the model oilseed Arabidopsis thaliana can be engineered to incorporate 16:0 into the middle position of TG. However, the fatty acyl composition of Arabidopsis seed TG does not mimic human milk, which is rich in both 16:0 and 18:1 and is defined by the high abundance of the TG molecular species 1,3-olein-2-palmitin (OPO). Here we have constructed an Arabidopsis fatty acid biosynthesis 1-1 fatty acid desaturase 2 fatty acid elongase 1 mutant with around 20% 16:0 and 70% 18:1 in its seeds and we have engineered it to esterify more than 80% of the 16:0 to the middle position of TG, using heterologous expression of the human lysophosphatidic acid acyltransferase isoform AGPAT1, combined with suppression of LYSOPHOSPHATIDIC ACID ACYLTRANSFERASE 2 and PHOSPHATIDYLCHOLINE:DIACYLGLYCEROL CHOLINEPHOSPHOTRANSFERASE. Our data show that oilseeds can be engineered to produce TG that is rich in OPO, which is a structured fat ingredient used in infant formulas. • Arabidopsis seeds were engineered to make the infant formula ingredient 1,3-olein-2-palmitin. • Seeds containing 20% palmitate and 70% oleate were produced by creating a fab1-1 fad2 fae1 triple mutant. • Palmitate was directed to the sn-2 position of triacylglycerol by expressing human AGPAT1 and by disrupting LPAT2 and PDCT. • 1,3-olein-2-palmitin accounts for 40% of the triacylglycerol molecules in the seed oil. [ABSTRACT FROM AUTHOR]

Maize is one of the most important crop species worldwide, but also extremely susceptible to the effects of increasingly higher temperatures and drought during the summer and its flowering and grain filling stage. Different strategies are being utilized to ensure a satisfying yield potential and quality even in the extremely unfavourable environmental conditions, which are the result of climate change. Some of them are cropping pattern changes and sowing alterations, including earlier sowing. Since this implies the exposure to suboptimal temperatures during early developmental stages, it leads to a demand for developing maize lines tolerant to low temperatures during these stages. This research focuses on the first phase of germination, imbibition. Maize tolerance to low temperatures is a complex trait that includes different mechanisms and strategies that all work together to ensure adaptation and survival, such as cell membrane changes, antioxidative system activation, etc. Additionally, the low temperature response of different maize inbreds varies substantially, so recognizing the different ways in which they respond to low temperatures during imbibition and other earlier stages of development is crucial. To accomplish this, seeds of two maize inbred lines of contrasting susceptibility to low temperatures were selected and exposed to control (20° C) and low temperature (8°C) conditions during the first 24h of imbition and then further analyzed to assess their response. This included germination and tetrazolium assays; ascertaining membrane integrity by evaluating cell leakage and lipid peroxidation; determining the antioxidative capacity by assessing superoxide dismutase (SOD) and catalase (CAT) activity; and expression analysis of four genes included in the low temperature response (gibberellin insensitive dwarf 1 gibberellin receptor, gid1; fatty acid desaturases 2 and 6, fad2 and fad6; plastid-lipid-associated 2 protein, pap2). The results showed that, while there is not a significant difference in their germination rate, they differ in their survival rate, with more seeds of the tolerant genotype surviving the low temperature period. Significant differences between them were found in cell leakage (p<0,01), as well as gid1(p<0,05) and fad6 (p<0,05) gene expression assays. The present research brings light to our understanding of the effect of low temperatures on the first germination stage, - imbibition. It highlights the importance of choosing the right inbreds for earlier sowing and points to certain routes that could be taken for improving and accelerating the breeding process for low temperature tolerance. [ABSTRACT FROM AUTHOR]

Backround. This study aimed to determine the effects of LC n-3 PUFA supplementation on the prevention and treatment of obesity and obesity-related diseases, and to compare the efficiency of different LC n-3 PUFA sources via biochemical and genetic mechanisms in rats. Methods. Male Wistar rats were randomized into four study groups, and fed with a standard diet, High Fat Diet (HFD), HFD+%2.5 Fish Oil (FO-HFD) or HFD+%2.5 Krill Oil (KO-HFD) for eight weeks. Food consumption, weight gain, serum glucose, insulin, ghrelin and leptin concentrations, lipid profile, liver fatty acid composition, and FADS1 and FADS2 mRNA gene expression levels were measured. Results. Weight gain in each HFD group was significantly higher than control group (p < 0.001), without any differences among them (p < 0.05). LC n-3 PUFAs modified lipid profile, but not glucose tolerance. Serum leptin levels were significantly higher in HFD groups than in the control group, however, no difference in serum ghrelin levels was observed among the groups. Liver n-3 fatty acid desaturation activity was higher (p = 0.74), and liver total lipid content was lower (p = 0.86) in KO-HFD compared to FO-HFD. FADS1 gene expression was highest in the HFD group (p < 0.001) while FADS2 gene expression was highest in the FO-HFD group (p < 0.001). Conclusion. LC n-3 PUFAs, especially krill oil, had moderate effects on lipid profile, but limited effects on obesity related parameters, suggesting different effects of different sources on gene expression levels. Further randomized controlled trials are needed to determine the efficacy of different LC n-3 PUFA sources in the prevention and treatment of obesity in humans. [ABSTRACT FROM AUTHOR]

Camellia oleifera Abel ('Huashuo') is an important woody oil species with high economic value. Low yield is the main factor restricting the rapid development of the tea-oil industry. The dynamics of sugars, oil, endogenous hormones, and the genes involved in these pathways, as well as the correlation with oil synthesis-related factors in Huashuo, were investigated. The results showed that oil content was positively correlated with sucrose and starch content but was negatively correlated with reducing sugar content. Pyruvate kinase (PK) and fructose-1,6-bisphosphate aldolase (FBA) of the glycolysis pathway could be beneficial for oil biosynthesis. Higher levels of acetyl CoA carboxylase (ACC), stearoyl-ACP desaturase (SAD), and WRINKLED1 (WRI1), as well as lower levels of omega-6 fatty acid desaturase 2 (FAD2) and lipoxygenase 5 (LOX5) could be responsible for the oil production. The higher expression of gibberellin 20 oxidase (GA20ox), lower expression of gibberellic acid insensitive (GAI), and the increase in 9-cis-epoxycarotenoid dioxygenase (NCED) at the mRNA level could contribute to oil accumulation. The results of this study could provide a reference for increasing the yield of plants related to Huashuo. [ABSTRACT FROM AUTHOR]

• Olfactory bulbectomy (OB)-induced depressive behaviours were attenuated in Fat-1 mice. • OB-induced abnormal phospholipids metabolic pathways were rectified in Fat-1 mice. • OB-increased CD11b and pro-inflammatory cytokines were reversed in Fat-1 mice. • Fat-1 mice expressed more anti-inflammatory lipid metabolic genes than wild-type mice. • Coproporphyrinogen III (Cop) were correlated with OB-induced hyperactivity. • Cop treatment enhanced pro-inflammatory cytokine and nitric oxide production in BV2. Depression is associated with abnormal lipid metabolism, and omega (n)-3 polyunsaturated fatty acids (PUFAs) can effectively treat depression. However, mechanism of lipid metabolism involved in the depressive attenuation remains poorly understood. Olfactory bulbectomy (OB)-induced changes in animal behavior and physiological functions are similar to those observed in depressed patients. Therefore, the present study used wild type (WT) and Fat-1 mice with or without OB to explore whether endogenous n-3 PUFA treatment of depression was through rectifying lipid metabolism, and to discover the possible lipid metabolic pathways. In WT mice, OB enhanced locomotor activity associated with up-regulation of lipid metabolites in the serum, such as phosphatidylcholines, L-a-glutamyl-L-Lysine and coproporphyrinogen III (Cop), which were involved in anti-inflammatory lipid metabolic pathways. OB also increased microglia activation marker CD11b and pro-inflammatory cytokines in the hippocampus. In one of the lipid pathways, increased Cop was significantly correlated with the hyper-activity of the OB mice. These OB-induced changes were markedly attenuated by endogenous n-3 PUFAs in Fat-1 mice. Additionally, increased expressions of anti-inflammatory lipid genes, such as fatty acid desaturase (Fads) and phospholipase A2 group VI (Pla2g6), were found in the hippocampus of Fat-1 mice compared with WT mice. Furthermore, Cop administration increased the production of pro-inflammatory cytokines and nitric oxide in a microglial cell line BV2. In conclusion, endogenous n-3 PUFAs in Fat-1 mice attenuated abnormal behavior in the depression model through restoration of lipid metabolism and suppression of inflammatory response. [ABSTRACT FROM AUTHOR]

The fatty acid desaturase FAD2 genes are the main contributors to oleic acid content, and different FAD2 alleles can result in different oleic acid contents in rapeseed oil. Hence, identification of allelic variation in FAD2 is an extremely desirable breeding goal. By performing QTL mapping using 190 F2:3 lines genotyped by genome-wide single nucleotide polymorphism (SNP) markers assayed by the Brassica 60 K Infinium BeadChip Array, four quantitative trait loci (QTL) for C18:1 content were mapped on chromosomes A01, A05, A09 and C05 over 3 years in a population segregating for oleic acid content. Two BnFAD2 genes on A05 and C05 were anchored within the QTL intervals, explaining 45–52 and 15–44% of the observed variation for C18:1 content. Sequence polymorphisms between the corresponding coding regions of the parental lines found two single-nucleotide polymorphisms (SNPs) in BnFAD2.A05 and BnFAD2.C05 , respectively, which led to the amino acid changes (C421T and G1073E) in the corresponding proteins. The mutation sites of Bnfad2.A05 and Bnfad2.C05 alleles were located within the second H-box and near the third H-box motif of the protein, respectively, and were found to be novel mutant alleles. Lines resulting from the combination of these two alleles contained up to 88% oleic acid in their seed oil, compared with 63% in wild-type controls. Two competitive allele-specific PCR (KASP) markers based on these two mutation sites were successfully developed and validated in segregating F2 populations. These markers will facilitate breeding for ultra-high seed oleic acid content in oilseed rape. [ABSTRACT FROM AUTHOR]

Deficiency of polyunsaturated fatty acids (PUFAs) is known to induce hepatic steatosis. However, it is not clearly understood which type of PUFA is responsible for the worsening of steatosis. This study observed a marked accumulation of hepatic triacylglycerol and cholesterol in fatty acid desaturase 2 knockout (FADS2−/−) mice lacking both C18 and ≥ C20 PUFAs that were fed a PUFA‐depleted diet. Hepatic triacylglycerol accumulation was associated with enhanced sterol regulatory element‐binding protein (SREBP)‐1‐dependent lipogenesis and decreased triacylglycerol secretion into the plasma via very‐low‐density lipoprotein (VLDL). Furthermore, upregulation of cholesterol synthesis contributed to increased hepatic cholesterol content in FADS2−/− mice. These results suggest that ≥ C20 PUFAs synthesized by FADS2 are important in regulating hepatic triacylglycerol and cholesterol accumulation during PUFA deficiency. [ABSTRACT FROM AUTHOR]

Objective: Unlike mammals, goose fatty liver shows a strong tolerance to fatty acids without obvious injury. Stearyl-coenzyme A desaturase 1 (SCD1) serves crucial role in desaturation of saturated fatty acids (SAFs), but its role in the SAFs tolerance of goose hepatocytes has not been reported. This study was conducted to explore the role of SCD1 in regulating palmitic acid (PA) tolerance of goose primary hepatocytes. Methods: 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide was examined to reflect the effect of PA on hepatocytes viability, and quantitative polymerase chain reaction was used to detect the mRNA levels of several genes related to endoplasmic reticulum (ER) stress, inflammation, and apoptosis, and the role of SCD1 in PA tolerance of goose hepatocytes was explored using RNA interfere. Results: Our results indicated that goose hepatocytes exhibited a higher tolerant capacity to PA than human hepatic cell line (LO2 cells). In goose primary hepatocytes, the mRNA levels of fatty acid desaturation-related genes (SCD1 and fatty acid desaturase 2) and fatty acid elongate enzyme-related gene (elongase of very long chain fatty acids 6) were significantly upregulated with 0.6 mM PA treatment. However, in LO2 cells, expression of ER stressrelated genes (x box-binding protein, binding immunoglobulin protein, and activating transcription factor 6), inflammatory response-related genes (interleukin-6 [IL-6], interleukin-1ß [IL-1ß], and interferon-γ) and apoptosis-related genes (bcl-2-associated X protein, b-cell lymphoma 2, Caspase-3, and Caspase-9) was significantly enhanced with 0.6 mM PA treatment. Additionally, small interfering RNA (siRNA) mediated downregulation of SCD1 significantly reduced the PA tolerance of goose primary hepatocytes under the treatment of 0.6 mM PA; meanwhile, the mRNA levels of inflammatory-related genes (IL-6 and IL-1ß) and several key genes involved in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT), forkhead box O1 (FoxO1), mammalian target of rapamycin and AMPK pathways (AKT1, AKT2, FoxO1, and sirtuin 1), as well as the protein expression of cytochrome C and the apoptosis rate were upregulated. Conclusion: In conclusion, our data suggested that SCD1 was involved in enhancing the PA tolerance of goose primary hepatocytes by regulating inflammation- and apoptosisrelated genes expression. [ABSTRACT FROM AUTHOR]

Background: Methods to increase the amount of omega-3 (n-3) PUFAs in milk are desirable for neonatal health. The n-3 PUFA, α-linolenic acid (18:3n-3), can be elongated to EPA (20:5n-3) and DHA (22:6n-3). n-6 PUFAs suppress tissue n-3 PUFA incorporation, but the effect of SFAs is not clear.Objectives: In this study, we compared the effects of SFAs and n-6 PUFAs on n-3 PUFA incorporation into milk and tissues of lactating mice and tissues of their offspring.Methods: Female CD-1 mice were bred at 8 wk of age. All experimental diets included 3% flaxseed oil and were begun on day 8 of lactation: low-fat diet (LFD); high-SFA diet (SAT), with an additional 12% saturated oil; or high-linoleic-acid diet (HLA), with 12% high-linoleic-acid oil (% kcal, carbohydrates:fat:protein: LFD, 49:24:27; both SAT and HLA, 35:46:19; n = 5/treatment). After 5 d, pup stomach milk clot FA profiles, tissue FA profiles in dams and pups, and mammary and hepatic expression of lipid metabolism genes in dams were analyzed. Data were analyzed by ANOVA with treatment diet as a fixed effect.Results: Dams in all groups had similar total milk fat concentrations, but both SAT and HLA decreased the concentration of n-3 PUFAs (SAT: -23%; HLA: -31%) compared with LFD, and HLA increased milk n-6 FAs by 347% compared with SAT. SAT pups had n-3 PUFA tissue concentrations similar to LFD, but HLA pups had lower n-3 PUFAs than SAT pups in multiple tissues (liver, -32%; kidney, -29%; heart, -28%; muscle, -18%). Mammary expression of lipid metabolism genes was mostly unchanged, but hepatic expression of elongases and desaturases was decreased with SAT compared with LFD [elongation of very-long-chain fatty acid (Elov)5, -42%; Elov6, -64%; fatty acid desaturase (Fads)1, -33%; Fads2, -44%].Conclusions: HLA decreased n-3 PUFA concentrations across multiple pup tissues compared with SAT. This suggests that high dietary n-6 PUFAs suppress n-3 PUFA incorporation in neonates. [ABSTRACT FROM AUTHOR]

Background: Biofortification is a novel method for improving the nutritional value of grains. Wheat is widely consumed worldwide. Thus, wheat zinc biofortification may improve the zinc status of populations.Objectives: We determined the effect of consuming zinc-biofortified wheat on plasma zinc concentrations and biomarkers of zinc-dependent functions in a controlled feeding study.Methods: Thirty-six healthy adult men, aged 18 to 51 y, participated in a 10-wk zinc-controlled feeding trial. After a 2-wk run-in period [metabolic period (MP) 1] (9.3 mg zinc/d and 2.1 g total phytate/d) to standardize zinc status, the participants consumed bread made from zinc-biofortified wheat (10.9 mg zinc/d) with no additional phytate (0.6 g/d total phytate) for 6 wk (MP2). During the final 2 wk (MP3), half of the men took a 25-mg zinc supplement daily to determine if the supplement further altered zinc status biomarkers. Repeated-measures linear regression methods were used to compare plasma zinc concentrations, fatty acid desaturase (FADS) activities, glutathione (GSH) concentrations, and DNA strand breaks assessed at enrollment and the end of each metabolic period.Results: Plasma zinc concentrations did not change throughout the study. From the end of MP1 to the end of MP2, the conversion of linoleic acid to γ-linolenic acid (FADS2 activity) increased from 0.020 to 0.025 (P = 0.02), and the conversion of dihomo-γ-linolenic acid to arachidonic acid (FADS1 activity) decreased from 6.37 to 5.53 (P = 0.01). GSH concentrations and DNA strand breaks did not change. Zinc supplementation (25 mg/d) in MP3 did not alter any of the endpoints.Conclusions: In healthy adult men, a 1.6-mg/d increase in dietary zinc from biofortified wheat modified FADS2 and FADS1 activities without changing DNA damage, plasma zinc, or GSH concentrations, demonstrating that FADS activities are more sensitive to small changes in zinc consumed with a meal. This trial was registered at clinicaltrials.gov as NCT03451214. [ABSTRACT FROM AUTHOR]

Soybean is an important oil crop cultivated worldwide. With the increasing global population crossed with growing challenging cultivation conditions, improving soybean breeding by selecting important traits is urgent needed. Genes coding for plant fatty acid desaturases (FADs) genes are major candidates for that, because they are involving in controlling fatty acid composition and holding membrane fluidity under abiotic stress. Here, 75 FADs were found in three soybean genomes, which were further classified into four sub-groups. Phylogenetic tree, gene structure, motif and promoter analysis showed that the FAD gene family was conserved in the three soybeans. In addition, the numbers of omega desaturase from Chinese cultivated varieties were significantly higher than those in Chinese wild soybean and ancient polyploid soybean, respectively. However, it was the opposite for the sphingolipid subfamily. These results indicated that each subfamily was subjected to different selection pressures during cultivation and domestication. As the extra genes of the subfamily were very close to other family members' positions on chromosomes, they should be produced by duplication. The cis -element analysis of FAD promoter sequences revealed that upstream sequences of FAD contained abundant light, hormone and abiotic stress responsive cis -elements, suggesting that the quality of soybean could be improved by regulating these stresses. Expression analysis of Chinese wild soybean under salt stress showed that GsDES1.1 , GsDES1.2 , GsFAD2.1 and GsSLD1 in leaves and GsSLD2 , GsSLD5 and GsSLD6 in roots were not closely related to salt stress response. Therefore, we explored the significant role of conserved, duplicated and neofunctionalized FAD in the domestication of soybean, which contributes to the importance of soybean as a global oil crop. • FAD evolution in three soybeans was analyzed. • Promoter analysis explored regulatory factors of FAD synthesis. • FAD subfamilies were subjected unequal selection pressures. • More GmFADs may own to gene replications. • FAD s was involved in response to drought stress. [ABSTRACT FROM AUTHOR]

Mammalian cells both import exogenous fatty acids and synthesize them de novo. Palmitate, the end product of fatty acid synthase (FASN) is a substrate for stearoyl-CoA desaturases (Δ-9 desaturases) that introduce a single double bond into fatty acyl-CoA substrates such as palmitoyl-CoA and stearoyl-CoA. This process is particularly upregulated in lipogenic tissues and cancer cells. Tracer methodology is needed to determine uptake versus de novo synthesis of lipids and subsequent chain elongation and desaturation. Here we describe an NMR method to determine the uptake of 13C-palmitate from the medium into HCT116 human colorectal cancer cells, and the subsequent desaturation and incorporation into complex lipids. Exogenous 13C 16 -palmitate was absorbed from the medium by HCT116 cells and incorporated primarily into complex glycerol lipids. Desaturase activity was determined from the quantification of double bonds in acyl chains, which was greatly reduced by ablation of the major desaturase SCD1. The NMR approach requires minimal sample preparation, is non-destructive, and provides direct information about the level of saturation and incorporation of fatty acids into complex lipids. [Display omitted] • An NMR method was developed to determine uptake and metabolism of fatty acids. • Desaturase activity was quantified in the acyl chains of complex lipids. • The method is non-destructive. • It provides direct information on fatty acid metabolism in cells. [ABSTRACT FROM AUTHOR]

Although antipsychotics constitute the best treatment for patients with schizophrenia, this treatment class carries a high risk of metabolic disarrangements thus developing metabolic syndrome (MetS). Altered fatty acid (FA) composition and desaturase indices have been associated with several metabolic diseases, including MetS. Herein, we determined fatty acid desaturase 1 (FADS1) and FADS2 gene expressions, serum delta-5 desaturase (D5D) and D6D indices in female adults with first-episode schizophrenia after olanzapine medication, as well as their relationship with the incidence of MetS. This study prospectively recruited 120 female patients with first-episode schizophrenia who completed 6-month olanzapine medication. Among these female patients, 31 patients developed MetS and 89 patients did not. The mRNA expression levels of FADS1 and FADS2 in patients were analyzed according to the presence of MetS and evaluation times with results of two-way ANOVAs (FADS1: P MetS = 0.0006, P time = 0.004, P interaction = 0.010; FADS2: P MetS = 0.012, P time < 0.0001, P interaction = 0.001). The D5D and D6D indices in patients were analyzed according to the presence of MetS and evaluation times with results of two-way ANOVAs (D5D: P MetS = 0.002, P time = 0.009, P interaction = 0.014; D6D: P MetS = 0.011, P time = 0.006, P interaction = 0.0001). The SCD-16 and SCD-18 indices in patients were analyzed according to the presence of MetS and evaluation times (SCD-16: P MetS = 0.005, P time = 0.009, P interaction = 0.016; SCD-18: P MetS = 0.037, P time = 0.382, P interaction = 0.163). The following multiple comparisons test showed the MetS exhibited reduced FADS1 mRNA expression and D5D index, increased FADS2 mRNA expression and D6D index, concomitant with an enhanced SCD-16 index, compared to the non-MetS did not after 6-month olanzapine medication. The study suggests changes of FADS1, FADS2 expressions, and fatty acid desaturase indices including D5D, D6D, and SCD-16 may be associated with the development of MetS in female adults with first-episode schizophrenia after olanzapine medication. • After 6-month olanzapine medication, schizophrenia patients with MetS had reduced FADS1 mRNA expression and D5D index. • After 6-month olanzapine medication, schizophrenia patients with MetS increased FADS2 mRNA expression and D6D index. • In the context of schizophrenia, MetS was associated with reduced FADS1 mRNA expression and D5D index. • In the context of schizophrenia, MetS was associated with increased FADS2 mRNA expression and D6D index compared to non-MetS. • Imbalance between fatty acid desaturase indices impairs metabolic homeostasis among female patients with schizophrenia. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "High-throughput diagnostic markers for foliar fungal disease resistance and high oleic acid content in groundnut" published in BMC Plant Biology. The authors identified minor typographical errors in the original article and provided the corrected versions. The errors were related to the description of the composition of groundnut oil and the function of the fatty acid desaturase enzyme. The corrected article has been published to address these errors. The publisher, Springer Nature, remains neutral and does not take any position on jurisdictional claims or institutional affiliations. [Extracted from the article]

The 18-amino acid peptide systemin is the first identified phytocytokine and plays important roles in tomato resistance to pathogens and insects. However, the function of systemin in postharvest fruit is unknown. Here, we found pretreatment of systemin increased the resistance of postharvest tomato fruit to Botrytis cinerea and the resistance ability was dependent on the concentration of systemin. As a phytocytokine, systemin induced the early immune responses in postharvest fruit, including the expression of immune-related genes, activation of mitogen-activated protein kinases (MAPKs), and production of reactive oxygen species. Transcriptome results indicated that systemin enhanced the expression of genes in the MAPK signaling pathway, phenypropanoid biosynthesis pathway and fatty acid desaturase (FAD) genes. Moreover, systemin regulated the activity of chitinase, phenylalanine ammonia lyase and peroxidase, and the concentration of FAD2 during storage. Therefore, our findings suggested that systemin could be a promising molecule to increase tomato fruit resistance against pathogens during storage. • Systemin increased the resistance of postharvest tomato fruit to Botrytis cinerea. • Systemin activated the early immune responses of fruit. • Systemin induced the activities of stress-related enzymes and the concentration of fatty acid desaturase 2. [ABSTRACT FROM AUTHOR]

The discovery of co-suppression in plants has greatly boosted the study of gene silencing mechanisms, but its triggering mechanism has remained a mystery. In this study, we explored its possible trigger mechanism by using Fatty acid desaturase 2 (FAD2) and Fatty acid elongase 1 (FAE1) strong co-suppression systems. Analysis of small RNAs in FAD2 co-suppression lines showed that siRNAs distributed throughout the coding region of FAD2 with an accumulated peak. However, mutations of the peak siRNA-matched site and siRNA derived site had not alleviated the co-suppression of its transgenic lines. Synthetic FAD2 (AtFAD2sm), which has synonymous mutations in the entire coding region, failed to trigger any co-suppression. Furthermore, 5′ and 3′ portions of AtFAD2 and AtFAD2sm were swapped to form two hybrid genes, AtFAD2–3sm and AtFAD2–5sm. 80 % and 92 % of their transgenic lines exhibited co-suppression, respectively. Finally, FAE1s with different degrees of the continuous sequence identity compared with AtFAE1 were tested in their Arabidopsis transgenic lines, and the results showed the co-suppression frequency was reduced as their continuous sequence identity stepped down. This work suggests that contiguous identity between the entire coding regions of transgenic and native genes rather than a special region is essential for a strong co-suppression. • Contiguous identity is essential for strong co-suppressions. [ABSTRACT FROM AUTHOR]

Abstract Background Linoleic acid is an important polyunsaturated fatty acid, required for all eukaryotes. Microsomal delta-12 (Δ12) oleate desaturase (FAD2) is a key enzyme for linoleic acid biosynthesis. Desert shrub Artemisia sphaerocephala is rich in linoleic acid, it has a large FAD2 gene family with twenty-six members. The aim of this work is to unveil the difference and potentially functionality of AsFAD2 family members. Results Full-length cDNAs of twenty-one AsFAD2 genes were obtained from A. sphaerocephala. The putative polypeptides encoded by AsFAD2 family genes showed a high level of sequence similarity and were relatively conserved during evolution. The motif composition was also relatively conservative. Quantitative real-time PCR analysis revealed that the AsFAD2–1 gene was strongly expressed in developing seeds, which may be closely associated with the high accumulating ability of linoleic acid in A. sphaerocephala seeds. Although different AsFAD2 family members showed diverse response to salt stress, the overall mRNA levels of the AsFAD2 family genes was stable. Transient expression of AsFAD2 genes in the Nicotiana benthamiana leaves revealed that the encoded proteins were all located in the endoplasmic reticulum. Heterologous expression in Saccharomyces cerevisiae suggested that only three AsFAD2 enzymes, AsFAD2–1, − 10, and − 23, were Δ12 oleate desaturases, which could convert oleic acid to linoleic acid, whereas AsFAD2–1 and AsFAD2–10 could also produce palmitolinoleic acid. Conclusions This research reported the cloning, expression studies, subcellular localization and functional identification of the large AsFAD2 gene family. These results should be helpful in understanding fatty acid biosynthesis in A. sphaerocephala, and has the potential to be applied in the study of plant fatty acids traits.

Klebsiella sp. strain AqSCr, isolated from Cr(VI)-polluted groundwater, reduces Cr(VI) both aerobically and anaerobically and resists up 34 mM Cr(VI); this resistance is independent of the ChrA efflux transporter. In this study, we report the whole genome sequence and the transcriptional profile by RNA-Seq of strain AqSCr under Cr(VI)-adapted conditions and found 255 upregulated and 240 downregulated genes compared to controls without Cr(VI) supplementation. Genes differentially transcribed were mostly associated with oxidative stress response, DNA repair and replication, sulfur starvation response, envelope-osmotic stress response, fatty acid (FA) metabolism, ribosomal subunits, and energy metabolism. Among them, genes not previously associated with chromium resistance, for example, cybB, encoding a putative superoxide oxidase (SOO), gltA2, encoding an alternative citrate synthase, and des, encoding a FA desaturase, were upregulated. The sodA gene encoding a manganese superoxide dismutase was upregulated in the presence of Cr(VI), whereas sodB encoding an iron superoxide dismutase was downregulated. Cr(VI) resistance mechanisms in strain AqSCr seem to be orchestrated by the alternative sigma factors fecl, rpoE, and rpoS (all of them upregulated). Membrane lipid analysis of the Cr(IV)-adapted strain showed a lower proportion of unsaturated lipids with respect to the control, which we hypothesized could result from unsaturated lipid peroxidation followed by degradation, together with de novo synthesis mediated by the upregulated FA desaturase-encoding gene, des. This report helps to elucidate both Cr(VI) toxicity targets and global bacterial response to Cr(VI).

Seed oils are used as edible oils and increasingly also for industrial applications. Although high-oleic seed oil is preferred for industrial use, most seed oil is high in polyunsaturated fatty acids (PUFAs) and low in monounsaturated fatty acids (MUFAs) such as oleic acid. Oil from Camelina, an emerging oilseed crop with a high seed oil content and resistance to environmental stress, contains 60% PUFAs and 30% MUFAs. Hexaploid Camelina carries three homoeologs of FAD2 , encoding fatty acid desaturase 2 (FAD2), which is responsible for the synthesis of linoleic acid from oleic acid. In this study, to increase the MUFA contents of Camelina seed oil, we generated CsFAD2 knockout plants via CRISPR-Cas9-mediated gene editing using the pRedU6fad2EcCas9 vector containing DsRed as a selection marker, the U6 promoter to drive a single guide RNA (sgRNA) covering the common region of the three CsFAD2 homoeologs, and an egg-cell-specific promoter to drive Cas9 expression. We analyzed CsFAD2 homoeolog-specific sequences by PCR using genomic DNA from transformed Camelina leaves. Knockout of all three pairs of FAD2 homoeologs led to a stunted bushy phenotype, but greatly enhanced MUFA levels (by 80%) in seeds. However, transformants with two pairs of CsFAD2 homoeologs knocked out but the other pair wild-type heterozygous showed normal growth and a seed MUFAs production increased up to 60%. These results provide a basis for the metabolic engineering of genes that affect growth in polyploid crops through genome editing. [ABSTRACT FROM AUTHOR]

Fatty acid desaturase catalyzes the desaturation reactions by insertion of double bonds into the fatty acyl chain, producing unsaturated fatty acids. Though soluble fatty acid desaturases have been studied widely in advanced organisms, there are very limited studies of membrane fatty acid desaturases due to the difficulty of generating recombinant desaturase. Brassica napus is a rapeseed, which possesses a range of different membrane-bound desaturases capable of producing fatty acids including Δ3, Δ4, Δ8, Δ9, Δ12, and Δ15 fatty acids. The 1155 bp open reading frame of Δ12 fatty acid desaturase (FAD12) from Brassica napus codes for 383 amino acid residues with a molecular weight of 44 kDa. It was expressed in Escherichia coli at 37 °C in soluble and insoluble forms when induced with 0.5 mM IPTG. Soluble FAD12 has been purified using Ni2+-Sepharose affinity chromatography with a total protein yield of 0.728 mg/mL. Gas chromatography–mass spectrometry (GC–MS) analysis revealed that desaturase activity of FAD12 could produce linoleic acid from oleic acid at a retention time of 17.6 with a conversion rate of 47%. Characterization of purified FAD12 revealed the optimal temperature of FAD12 was 50 °C with 2 mM preferred substrate concentration of oleic acid. Analysis of circular dichroism (CD) showed FAD12 was made up of 47.3% and 0.9% of alpha-helix and β-sheet secondary structures. The predicted Tm value was 50.2 °C. • Expression of membrane-bound FAD12 from Brassica napus in Escherichia coli in soluble and insoluble forms. • FAD12 protein has been purified using Ni2+-Sepharose affinity chromatography. • Functional activity of FAD12 desaturase by conversion of linoleic acid from oleic acid was conducted by GC-MS [ABSTRACT FROM AUTHOR]

Background: Increases in the red blood cell (RBC) degree of fatty acid desaturation are reported in response to exercise, aging, or diseases associated with systemic oxidant stress. However, no studies have focused on the presence and activity of fatty acid desaturases (FADS) in the mature RBC.Study Design and Methods: Steady state metabolomics and isotope-labeled tracing experiments, immunofluorescence approaches, and pharmacological interventions were used to determine the degree of fatty acid unsaturation, FADS activity as a function of storage, oxidant stress, and G6PD deficiency in human and mouse RBCs.Results: In 250 blood units from the REDS III RBC Omics recalled donor population, we report a storage-dependent accumulation of free mono-, poly-(PUFAs), and highly unsaturated fatty acids (HUFAs), which occur at a faster rate than saturated fatty acid accumulation. Through a combination of immunofluorescence, pharmacological inhibition, tracing experiments with stable isotope-labeled fatty acids, and oxidant challenge with hydrogen peroxide, we demonstrate the presence and redox-sensitive activity of FADS2, FADS1, and FADS5 in the mature RBC. Increases in PUFAs and HUFAs in human and mouse RBCs correlate negatively with storage hemolysis and positively with posttransfusion recovery. Inhibition of these enzymes decreases accumulation of free PUFAs and HUFAs in stored RBCs, concomitant to increases in pyruvate/lactate ratios. Alterations of this ratio in G6PD deficient patients or units supplemented with pyruvate-rich rejuvenation solutions corresponded to decreased PUFA and HUFA accumulation.Conclusion: Fatty acid desaturases are present and active in mature RBCs. Their activity is sensitive to oxidant stress, storage duration, and alterations of the pyruvate/lactate ratio. [ABSTRACT FROM AUTHOR]

Linoleic acid (LA) has garnered much attention due to its potential applications in the oleochemical and nutraceutical industries. The oleaginous yeast Rhodotorula toruloides has outstanding lipogenecity, and is considered a potential alternative to the current plant-based platforms for LA production. Δ12-fatty acid desaturases (Δ12-Fads) are involved in LA synthesis in various fungi and yeasts, but their functions in R. toruloides remain poorly understood. To achieve the production of LA-rich lipids in R. toruloides , we investigated the function of the native Δ12-FAD (RtFAD2). First, the overexpression of RtFAD2 and its co-overexpression with RtFAD1 (encoding R. toruloides Δ9-Fad) and their effects on LA production in R. toruloides were investigated. The function of Rt Fad2 was confirmed by heterologous expression in Saccharomyces cerevisiae. Overexpression of RtFAD2 significantly elevated the LA contents and titers in the wild-type strain R. toruloides DMKU3-TK16 (TK16) and in a thermotolerant derivative of TK16 (L1-1). Additionally, overexpression of RtFAD2 in R. toruloides strains also increased the lipid titer and content. Overexpression of RtFAD1 was down-regulated in the RtFAD1 and RtFAD2 co-overexpressing strains, suggesting that the elevated LA content may function as a key regulator of RtFAD1 expression to control C18 fatty-acid synthesis in R. toruloides. We characterized the function of RtFAD2 and showed that its overexpression in R. toruloides increased the lipid and LA production. These findings may assist in the rational design of metabolic engineering related to LA or polyunsaturated fatty acid production in R. toruloides. [Display omitted] [ABSTRACT FROM AUTHOR]

Grapevine (Vitis vinifera L.) is prone to fungal and oomycete diseases. Downy and powdery mildews and grey mold, are caused by Plasmopara viticola, Erisiphe necator and Botrytis cinerea, respectively. P. viticola and E. necator are obligatory biotrophs whereas B. cinerea is a necrotroph. In tolerant grapevine cultivars, plant-pathogen interaction induces defence responses, including metabolite and protein accumulation and hypersensitive reaction. Lipid and lipid-derived molecules may have a key role in the activation of defence mechanisms. Previous results suggest that V. vinifera cv Regent tolerance to P. viticola may be mediated in the first hours post inoculation by fatty acid (FA) associated signalling. In the present study we characterized FA modulation in V. vinifera cv Regent leaves upon inoculation with P. viticola , E. necator and B. cinerea and correlated FA modulation with the expression profiles of genes encoding the FA desaturases FAD6 and FAD8. In all the interactions, a progressive desaturation of stearic acid to α-linolenic acid, precursor of jasmonic acid, occurred, which was observed for a longer period against B. cinerea. Our results provide evidence of a distinct FA meditated signalling pattern in grapevine interaction with biotrophs and necrotrophs. While the interaction with the biotrophs may trigger a higher synthesis of polyunsaturated FA (PUFA) at early time-points with a tendency to return to basal levels, the interaction with B. cinerea may trigger a later and more durable induction of PUFA synthesis. In all interactions, membrane fluidity modulation occurred, which may be crucial to maintain cellular function during infection. • Fatty acid signalling is differentially modulated in grapevine defence to P. viticola , E. necator and B. cinerea. • α-linolenic acid synthesis is induced in the first hours against biotrophs, and later against the necrotroph. • The interaction with biotrophs and the necrotroph triggers different FAD6 and FAD8 expression patterns. • An adjustment of the fatty acids degree of unsaturation occurs during the infection. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) displays marked cellular and metabolic heterogeneity that varies among cellular microenvironments within a tumor. Metabolic targeting has long been advocated as a therapy against many tumors including GBM, but how lipid metabolism is altered to suit different microenvironmental conditions and whether cancer stem cells (CSCs) have altered lipid metabolism are outstanding questions in the field. We interrogated gene expression in separate microenvironments of GBM organoid models that mimic the transition between nutrient-rich and nutrient-poor pseudopalisading/perinecrotic tumor zones using spatial-capture RNA-sequencing. We revealed a striking difference in lipid processing gene expression and total lipid content between diverse cell populations from the same patient, with lipid enrichment in hypoxic organoid cores and also in perinecrotic and pseudopalisading regions of primary patient tumors. This was accompanied by regionally restricted upregulation of hypoxia-inducible lipid droplet-associated (HILPDA) gene expression in organoid cores and pseudopalisading regions of clinical GBM specimens, but not lower-grade brain tumors. CSCs have low lipid droplet accumulation compared to non-CSCs in organoid models and xenograft tumors, and prospectively sorted lipid-low GBM cells are functionally enriched for stem cell activity. Targeted lipidomic analysis of multiple patient-derived models revealed a significant shift in lipid metabolism between GBM CSCs and non-CSCs, suggesting that lipid levels may not be simply a product of the microenvironment but also may be a reflection of cellular state. CSCs had decreased levels of major classes of neutral lipids compared to non-CSCs, but had significantly increased polyunsaturated fatty acid production due to high fatty acid desaturase (FADS1/2) expression which was essential to maintain CSC viability and self-renewal. Our data demonstrate spatially and hierarchically distinct lipid metabolism phenotypes occur clinically in the majority of patients, can be recapitulated in laboratory models, and may represent therapeutic targets for GBM. [ABSTRACT FROM AUTHOR]

Klebsiella sp. strain AqSCr, isolated from Cr(VI)-polluted groundwater, reduces Cr(VI) both aerobically and anaerobically and resists up 34 mM Cr(VI); this resistance is independent of the ChrA efflux transporter. In this study, we report the whole genome sequence and the transcriptional profile by RNA-Seq of strain AqSCr under Cr(VI)-adapted conditions and found 255 upregulated and 240 downregulated genes compared to controls without Cr(VI) supplementation. Genes differentially transcribed were mostly associated with oxidative stress response, DNA repair and replication, sulfur starvation response, envelope-osmotic stress response, fatty acid (FA) metabolism, ribosomal subunits, and energy metabolism. Among them, genes not previously associated with chromium resistance, for example, cybB , encoding a putative superoxide oxidase (SOO), gltA2 , encoding an alternative citrate synthase, and des , encoding a FA desaturase, were upregulated. The sodA gene encoding a manganese superoxide dismutase was upregulated in the presence of Cr(VI), whereas sodB encoding an iron superoxide dismutase was downregulated. Cr(VI) resistance mechanisms in strain AqSCr seem to be orchestrated by the alternative sigma factors fecl , rpoE , and rpoS (all of them upregulated). Membrane lipid analysis of the Cr(IV)-adapted strain showed a lower proportion of unsaturated lipids with respect to the control, which we hypothesized could result from unsaturated lipid peroxidation followed by degradation, together with de novo synthesis mediated by the upregulated FA desaturase-encoding gene, des. This report helps to elucidate both Cr(VI) toxicity targets and global bacterial response to Cr(VI). [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKNs) are among the most devastating pests in agriculture. Solanum torvum Sw. (Turkey berry) has been used as a rootstock for eggplant (aubergine) cultivation because of its resistance to RKNs, including Meloidogyne incognita and M. arenaria. We previously found that a pathotype of M. arenaria , A2-J, is able to infect and propagate in S. torvum. In vitro infection assays showed that S. torvum induced the accumulation of brown pigments during avirulent pathotype A2-O infection, but not during virulent A2-J infection. This experimental system is advantageous because resistant and susceptible responses can be distinguished within a few days, and because a single plant genome can yield information about both resistant and susceptible responses. Comparative RNA-sequencing analysis of S. torvum inoculated with A2-J and A2-O at early stages of infection was used to parse the specific resistance and susceptible responses. Infection with A2-J did not induce statistically significant changes in gene expression within one day post-inoculation (DPI), but afterward, A2-J specifically induced the expression of chalcone synthase, spermidine synthase, and genes related to cell wall modification and transmembrane transport. Infection with A2-O rapidly induced the expression of genes encoding class III peroxidases, sesquiterpene synthases, and fatty acid desaturases at 1 DPI, followed by genes involved in defense, hormone signaling, and the biosynthesis of lignin at 3 DPI. Both isolates induced the expression of suberin biosynthetic genes, which may be triggered by wounding during nematode infection. Histochemical analysis revealed that A2-O, but not A2-J, induced lignin accumulation at the root tip, suggesting that physical reinforcement of cell walls with lignin is an important defense response against nematodes. The S. torvum -RKN system can provide a molecular basis for understanding plant-nematode interactions. [ABSTRACT FROM AUTHOR]

ω3 Polyunsaturated fatty acids are currently obtained mainly from fisheries; thus, sustainable alternative sources such as oleaginous microorganisms are required. Here, we describe the isolation, characterization, and application of 3 novel ω3 desaturases with ω3 polyunsaturated fatty acid–producing activity at ordinary temperatures (28 °C). First, we selected Pythium sulcatum and Plectospira myriandra after screening for oomycetes with high eicosapentaenoic acid/arachidonic acid ratios and isolated the genes psulω3 and pmd17 , respectively, which encode ω3 desaturases. Subsequent characterization showed that PSULω3 exhibited ω3 desaturase activity on both C18 and C20 ω6 polyunsaturated fatty acids while PMD17 exhibited ω3 desaturase activity exclusively on C20 ω6 polyunsaturated fatty acids. Expression of psulω3 and pmd17 in the arachidonic acid–producer Mortierella alpina resulted in transformants that produced eicosapentaenoic acid/total fatty acid values of 38% and 40%, respectively, at ordinary temperatures. These ω3 desaturases should facilitate the construction of sustainable ω3 polyunsaturated fatty acid sources. [ABSTRACT FROM AUTHOR]

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Background: Defining the origin of genetic novelty is central to our understanding of the evolution of novel traits. Diversification among fatty acid desaturase (FAD) genes has played a fundamental role in the introduction of structural variation in fatty acyl derivatives. Because of its central role in generating diversity in insect semiochemicals, the FAD gene family has become a model to study how gene family expansions can contribute to the evolution of lineage-specific innovations. Here we used the codling moth (Cydia pomonella) as a study system to decipher the proximate mechanism underlying the production of the ∆8∆10 signature structure of olethreutine moths. Biosynthesis of the codling moth sex pheromone, (E8,E10)-dodecadienol (codlemone), involves two consecutive desaturation steps, the first of which is unusual in that it generates an E9 unsaturation. The second step is also atypical: it generates a conjugated diene system from the E9 monoene C12 intermediate via 1,4-desaturation. Results: Here we describe the characterization of the FAD gene acting in codlemone biosynthesis. We identify 27 FAD genes corresponding to the various functional classes identified in insects and Lepidoptera. These genes are distributed across the C. pomonella genome in tandem arrays or isolated genes, indicating that the FAD repertoire consists of both ancient and recent duplications and expansions. Using transcriptomics, we show large divergence in expression domains: some genes appear ubiquitously expressed across tissue and developmental stages; others appear more restricted in their expression pattern. Functional assays using heterologous expression systems reveal that one gene, Cpo_CPRQ, which is prominently and exclusively expressed in the female pheromone gland, encodes an FAD that possesses both E9 and ∆8∆10 desaturation activities. Phylogenetically, Cpo_CPRQ clusters within the Lepidoptera-specific ∆10/∆11 clade of FADs, a classic reservoir of unusual desaturase activities in moths. Conclusions: Our integrative approach shows that the evolution of the signature pheromone structure of olethreutine moths relied on a gene belonging to an ancient gene expansion. Members of other expanded FAD subfamilies do not appear to play a role in chemical communication. This advises for caution when postulating the consequences of lineage-specific expansions based on genomics alone. [ABSTRACT FROM AUTHOR]

Objective: Effects of linseed oil (LO) supplementation on the fat content and fatty acid profile of breast meat, and the expression of three genes in the liver, breast muscle and fat tissues of commercial 154-day-old hybrid male turkeys were investigated. Methods: The animals in the control group were fed a commercially available feed and received no LO supplementation (n = 70), whereas animals in the LO group (n = 70) were fed the same basic diet supplemented with LO (day 15 to 21, 0.5%; day 22 to 112, 1%). The effect of dietary LO supplementation on fatty acid composition of breast muscle was examined by gas chromatography, and the expression of fatty acid desaturase 2 (FADS2), peroxisome proliferator activated receptor gamma (PPARγ), and insulin-like growth factor 1 (IGF1) genes was analysed by means of quantitative reverse transcription polymerase chain reaction. Results: The LO supplementation affected the fatty acid composition of breast muscle. Hepatic FADS2 levels were considerably lower (p<0.001), while adipose tissue expression was higher (p<0.05) in the control compared to the LO group. The PPARγ expression was lower (p<0.05), whereas IGF1 was higher (p<0.05) in the fat of control animals. There were no significant (p>0.05) differences in FADS2, PPARγ, and IGF1 gene expressions of breast muscle; however, omega-6/omega-3 ratio of breast muscle substantially decreased (p<0.001) in the LO group compared to control. Conclusion: Fatty acid composition of breast meat was positively influenced by LO supplementation without deterioration of fattening parameters. Remarkably, increased FADS2 expression in the liver of LO supplemented animals was associated with a significantly decreased omega-6/omega-3 ratio, providing a potentially healthier meat product for human consumption. Increased PPARγ expression in fat tissue of the LO group was not associated with fat content of muscle, whereas a decreased IGF1 expression in fat tissue was associated with a trend of decreasing fat content in muscle of the experimental LO group. [ABSTRACT FROM AUTHOR]

Algal lipids are important molecules to store energy in algae and transfer energy in the marine food chain, and are potential materials for high value nutraceuticals (e.g., omega‐3 fatty acids) or biofuel production. However, how lipid biosynthesis is regulated is not well understood in many species including Eutreptiella from the phylum of Euglenozoa. Here, we characterized the fatty acid (FA) profile of an Eutreptiella species isolated from Long Island Sound, USA, using gas chromatography–tandem mass spectrometry (GC/MS/MS) and investigated their biosynthesis pathways by transcriptome sequencing. We discovered 24 types of FAs including a relatively high proportion of long‐chain unsaturated FAs. The abundances of C16, C18, and saturated FAs decreased when phosphate in the culture medium was depleted. Among the 24 FAs, docosahexaenoic acid (C22:6∆4,7,10,13,16,19) was most abundant, suggesting that Eutreptiella sp. preferentially invests in the synthesis of long‐chain polyunsaturated fatty acids (LC‐PFAs). Further transcriptomic analysis revealed that Eutreptiella sp. likely synthesizes LC‐PFAs via ∆8 pathway and uses type I and II fatty acid synthases. Using RT–qPCR, we found that some of the lipid synthesis genes, such as β‐ketoacyl‐ACP reductase, fatty acid desaturase, acetyl‐CoA carboxylase, acyl carrier protein, ∆8 desaturase, and Acyl‐ACP thioesterase, were more actively expressed during light period, and two carbon fixation genes were up‐regulated in the high‐lipid illuminated cultures, suggesting a linkage between photosynthesis and lipid production. The lipid profile renders Eutreptiella sp. a nutritional prey and valuable source for nutraceuticals, and the biosynthesis pathway documented here will be useful for future research and applications. [ABSTRACT FROM AUTHOR]

Purpose: Long-chain polyunsaturated fatty acids (LCPUFA) can be synthesised endogenously from linoleic acid (LA) and α-linolenic acid (ALA) in a pathway involving the fatty acid desaturase (FADS) genes. Endogenous synthesis is inefficient; therefore, dietary intake of preformed LCPUFA from their richest source of fish is preferred. This study investigated the effect of fish consumption on PUFA concentrations in women of childbearing age while stratifying by FADS genotype. The influence of fish consumption on lipid profile, and markers of inflammation and oxidative stress was also examined. Methods: Healthy women (n = 49) provided a buccal swab which was analysed for FADS2 genotype (rs3834458; T/deletion). Participants were stratified according to genotype and randomised to an intervention group to receive either no fish (n = 18), 1 portion (n = 14) or 2 portions (n = 17) (140 g per portion) of fish per week for a period of 8 weeks. Serum PUFA was analysed at baseline and post-intervention. Lipid profile, and markers of inflammation and oxidative stress were also analysed. Results: Participants consuming 2 portions of fish per week had significantly higher concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and total n-3 PUFA, and a lower n-6:n-3 ratio compared to those in the no fish or 1 portion per week group (all p < 0.05). Fish consumption did not have a significant effect on biomarkers of oxidative stress, inflammation and lipid profile in the current study. Conclusion: Consumption of 2 portions of fish per week has beneficial effects on biological n-3 PUFA concentrations in women of childbearing age; however, no effects on oxidative stress, inflammation or lipid profile were observed. This trial was registered at www.clinicaltrials.gov (NCT03765580), registered December 2018. [ABSTRACT FROM AUTHOR]

Membrane-bound fatty acid desaturase (FAD) gene family plays crucial roles in regulation of fatty acid (FA) compositions in plants. Sunflower (Helianthus annuus L.) is an important oilseed crop in the world; however, no comprehensive study on exploring the role of FAD family in relation to stress tolerance in sunflower has been performed yet. In this study, we identified 40 putative FAD genes in H. annuus (HaFAD), which were unevenly distributed across 13 of the total 17 chromosomes. Phylogenetic analysis indicated that HaFAD genes were divided into four subfamilies, as supported by highly conserved gene structures and motifs. Collinearity analysis showed that tandem duplication events played a crucial role in the expansion of HaFAD gene family. In addition, tissue-specific expression showed that 32 HaFAD genes were widely expressed in various tissues or organs of sunflower. Furthermore, qRT-PCR results revealed significant expression changes of HaFAD genes in response to abiotic (cadmium, drought) and biotic (Orobanche cumana) stresses, suggesting their important functions in response to different stresses. Therefore, our results provide insights into HaFAD gene family in response to different stresses, and some specific up-regulated genes such as HaFAD3.2 , HaADS8 , HaFAD2.1 , and HaADS9 would be the potential candidate genes for the sunflower tolerance breeding. • A total of 40 FAD genes were identified in Helianthus annuus L. • Genome-wide characterization of FAD family was conducted in sunflower. • The heatmap of 32 HaFAD s in ten different tissues and organs was established. • 33 selected HaFAD s were differentially expressed under biotic and abiotic stresses. [ABSTRACT FROM AUTHOR]

BACKGROUND: PfFAD3 transgenic soybean expressing omega‐3 fatty acid desaturase 3 of Physaria produces increased level of α‐linolenic acid in seed. Composition data of non‐transgenic conventional varieties is important in the safety assessment of the genetically‐modified (GM) crops in the context of the natural variation. RESULTS: The natural variation was characterized in seed composition of 13 Korean soybean varieties grown in three locations in South Korea for 2 years. Univariate analysis of combined data showed significant differences by variety and cultivation environment for proximates, minerals, anti‐nutrients, and fatty acids. Percent variability analysis demonstrated that genotype, environment and the interaction of environment with genotype contributed to soybean seed compositions. Principal component analysis and orthogonal projections to latent structure discriminant analysis indicated that significant variance in compositions was attributable to location and cultivation year. The composition of three PfFAD3 soybean lines for proximates, minerals, anti‐nutrients, and fatty acids was compared to a non‐transgenic commercial comparator (Kwangankong, KA), and three non‐transgenic commercial varieties grown at two sites in South Korea. Only linoleic and linolenic acids significantly differed in PfFAD3‐1 lines compared to KA, which were expected changes by the introduction of the PfFAD3‐1 trait in KA. CONCLUSION: Genotype, environment, and the interaction of environment with genotype contributed to compositional variability in soybean. PfFAD3‐1 soybean is equivalent to the conventional varieties with respect to these components. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The editorial discusses the use of omega-3 polyunsaturated fatty acids (PUFAs) in preventing cardiovascular risk in individuals with metabolic syndrome. The study analyzed the effectiveness of icosapent ethyl (IPE), an EPA formulation, in reducing cardiovascular events in patients with metabolic syndrome. The results showed that IPE had beneficial effects on the primary composite endpoint, including myocardial infarction, coronary revascularization, and unstable angina. However, it did not significantly reduce the risk of cardiovascular death and stroke in this subgroup. The study suggests that IPE may reduce the high cardiovascular risk associated with metabolic syndrome, despite lacking robust effects on metabolic syndrome components. Further research is needed to identify factors that determine individual responses to omega-3 PUFA treatment. [Extracted from the article]

Fatty acid composition of olive oil has an important effect on the oil quality to such an extent that oils with a high oleic and low linoleic acid contents are preferable from a nutritional and technological point of view. In the present work, we have first studied the diversity of the fatty acid composition in a set of eighty-nine olive cultivars from the Worldwide Olive Germplasm Bank of IFAPA Cordoba (WOGBC-IFAPA), and in a core collection (Core-36), which includes 28 olive cultivars from the previously mentioned set. Our results indicate that oleic and linoleic acid contents displayed the highest degree of variability of the different fatty acids present in the olive oil of the 89 cultivars under study. In addition, the independent study of the Core-36 revealed two olive cultivars, Klon-14 and Abou Kanani, with extremely low and high linoleic acid contents, respectively. Subsequently, these two cultivars were used to investigate the specific contribution of different fatty acid desaturases to the linoleic acid content of mesocarp tissue during olive fruit development and ripening. Fatty acid desaturase gene expression levels, together with lipid analysis, suggest that not only OeFAD2-2 and OeFAD2-5 but also the different specificities of extraplastidial acyltransferase enzymes are responsible for the variability of the oleic/linoleic acid ratio in olive cultivars. All this information allows for an advancement in the knowledge of the linoleic acid biosynthesis in different olive cultivars, which can impact olive breeding programs to improve olive oil quality.

Olive (Olea europaea L.) is a world-famous woody oil tree and popular for redundant unsaturated fatty acids. Fatty acid desaturase (FAD) genes are responsible for fatty acid desaturation and stress regulation but have not yet been identified in olive at the whole genome level. This study identified 40 and 27 FAD genes in the cultivated olive O. europaea cv. Farga and the wild olive O. europaea var. Sylvestris, respectively. Phylogenetic analysis showed that all the FAD genes could be classified into the soluble FAB2/SAD clade and membrane-bound clade, including ADS/FAD5, DES, FAD4, SLD, ω-6 and ω-3, with the high consistency of subcellular localization, motif composition and exon-intron organization in each group. FAD genes in olive showed the diverse functional differentiation in morphology of different tissues, fruit development and stress responses. Among them, OeFAB2.8 and OeFAD2.3 were up-regulated and OeADS.1, OeFAD4.1 and OeFAD8.2 were down-regulated under the wound, Verticillium dahliae and cold stresses. This study presents a comprehensive analysis of the FAD genes at the whole-genome level in olives and will provide guidance for the improvement of oil quality or stress tolerance of olive trees.

Perilla, also termed as purple mint, Chinese basil, or Perilla mint, is a flavoring herb widely used in East Asia. Both crude oil and essential oil are employed for consumption as well as industrial purposes. Fatty acids (FAs) biosynthesis and oil body assemblies in Perilla have been extensively investigated over the last three decades. Recent advances have been made in order to reveal the enzymes involved in the fatty acid biosynthesis in Perilla. Among those fatty acids, alpha-linolenic acid retained the attention of scientists mainly due to its medicinal and nutraceutical properties. Lipids synthesis in Perilla exhibited similarities with Arabidopsis thaliana lipids’ pathway. The homologous coding genes for polyunsaturated fatty acid desaturases, transcription factors, and major acyl-related enzymes have been found in Perilla via de novo transcriptome profiling, genome-wide association study, and in silico whole-genome screening. The identified genes covered de novo fatty acid synthesis, acyl-CoA dependent Kennedy pathway, acyl-CoA independent pathway, Triacylglycerols (TAGs) assembly, and acyl editing of phosphatidylcholine. In addition to the enzymes, transcription factors including WRINKLED, FUSCA3, LEAFY COTYLEDON1, and ABSCISIC ACID INSENSITIVE3 have been suggested. Meanwhile, the epigenome aspect impacting the transcriptional regulation of FAs is still unclear and might require more attention from the scientific community. This review mainly outlines the identification of the key gene master players involved in Perilla FAs biosynthesis and TAGs assembly that have been identified in recent years. With the recent advances in genomics resources regarding this orphan crop, we provided an updated overview of the recent contributions into the comprehension of the genetic background of fatty acid biosynthesis. The provided resources can be useful for further usage in oil-bioengineering and the design of alpha-linolenic acid-boosted Perilla genotypes in the future.

Chlamydomonas reinhardtii cells exposed to abiotic stresses (e.g. nitrogen, zinc, or phosphorus deficiency) accumulate triacylglycerols (TAG), which are stored in lipid droplets. Here, we report that iron starvation leads to formation of lipid droplets and accumulation of TAGs. This occurs between 12 and 24 h after the switch to iron-starvation medium. C. reinhardtii cells deprived of iron have more saturated fatty acid (FA), possibly due to the loss of function of FA desaturases, which are iron-requiring enzymes with diiron centers. The abundance of a plastid acyl-ACP desaturase (FAB2) is decreased to the same degree as ferredoxin. Ferredoxin is a substrate of the desaturases and has been previously shown to be a major target of the iron deficiency response. The increase in saturated FA (C16:0 and C18:0) is concomitant with the decrease in unsaturated FA (C16:4, C18:3, or C18:4). This change was gradual for diacylglyceryl-N,N,N-trimethylhomoserine (DGTS) and digalactosyldiacylglycerol (DGDG), whereas the monogalactosyldiacylglycerol (MGDG) FA profile remained stable during the first 12 h, whereas MGDG levels were decreasing over the same period of time. These changes were detectable after only 2 h of iron starvation. On the other hand, DGTS and DGDG contents gradually decreased until a minimum was reached after 24-48 h. RNA-Seq analysis of iron-starved C. reinhardtii cells revealed notable changes in many transcripts coding for enzymes involved in FA metabolism. The mRNA abundances of genes coding for components involved in TAG accumulation (diacylglycerol acyltransferases or major lipid droplet protein) were increased. A more dramatic increase at the transcript level has been observed for many lipases, suggesting that major remodeling of lipid membranes occurs during iron starvation in C. reinhardtii.

Reutealis trisperma oil is a new source for biodiesel production. The predominant fatty acids in this plant are stearic acid (9%), palmitic acid (10%), oleic acid (12%), linoleic acid (19%), and α-eleostearic acid (51%). The presence of polyunsaturated fatty acids (PUFAs), linoleic acid, and α-eleostearic acid decreases the oxidation stability of R. trisperma biodiesel. Although several studies have suggested that the fatty acid desaturase 2 (FAD2) enzyme is involved in the regulation of fatty acid desaturation, little is known about the genetic information of FAD2 in R. trisperma. The objectives of this study were to isolate, characterize, and determine the relationship between the R. trisperma FAD2 fragment and other Euphorbiaceae plants. cDNA fragments were isolated using reverse transcription polymerase chain reaction (PCR). The DNA sequence obtained by sequencing was used for further analysis. In silico analysis identified the fragment identity, subcellular localization, and phylogenetic construction of the R. trisperma FAD2 cDNA fragment and Euphorbiaceae. The results showed that a 923-bp partial sequence of R. trisperma FAD2 was successfully isolated. Based on in silico analysis, FAD2 was predicted to encode 260 amino acids, had a domain similarity with Omega-6 fatty acid desaturase, and was located in the endoplasmic reticulum membrane. The R. trisperma FAD2 fragment was more closely related to Vernicia fordii (HM755946.1). [ABSTRACT FROM AUTHOR]

Background: Rhodotorula toruloides is a robust producer of triacylglycerol owing to its fast growth rate and strong metabolic flux under conditions of high cell density fermentation. However, the molecular basis of fatty acid biosynthesis, desaturation and regulation remains elusive. Results: We present the molecular characterization of four fatty acid desaturase (FAD) genes in R. toruloides. Biosynthesis of oleic acid (OA) and palmitoleic acid (POA) was conferred by a single-copy ∆9 Fad (Ole1) as targeted deletion of which abolished the biosynthesis of all unsaturated fatty acids. Conversion of OA to linoleic acid (LA) and α-linolenic acid (ALA) was predominantly catalyzed by the bifunctional ∆12/∆15 Fad2. FAD4 was found to encode a trifunctional ∆9/∆12/∆15 FAD, playing important roles in lipid and biomass production as well as stress resistance. Furthermore, an abundantly transcribed OLE1-related gene, OLE2 encoding a 149-aa protein, was shown to regulate Ole1 regioselectivity. Like other fungi, the transcription of FAD genes was controlled by nitrogen levels and fatty acids in the medium. A conserved DNA motif, (T/C)(G/A)TTGCAGA(T/C)CCCAG, was demonstrated to mediate the transcription of OLE1 by POA/OA. The applications of these FAD genes were illustrated by engineering high-level production of OA and γ-linolenic acid (GLA). Conclusion: Our work has gained novel insights on the transcriptional regulation of FAD genes, evolution of FAD enzymes and their roles in UFA biosynthesis, membrane stress resistance and, cell mass and total fatty acid production. Our findings should illuminate fatty acid metabolic engineering in R. toruloides and beyond. [ABSTRACT FROM AUTHOR]

Fatty acid composition of olive oil has an important effect on the oil quality to such an extent that oils with a high oleic and low linoleic acid contents are preferable from a nutritional and technological point of view. In the present work, we have first studied the diversity of the fatty acid composition in a set of eighty-nine olive cultivars from the Worldwide Olive Germplasm Bank of IFAPA Cordoba (WOGBC-IFAPA), and in a core collection (Core-36), which includes 28 olive cultivars from the previously mentioned set. Our results indicate that oleic and linoleic acid contents displayed the highest degree of variability of the different fatty acids present in the olive oil of the 89 cultivars under study. In addition, the independent study of the Core-36 revealed two olive cultivars, Klon-14 and Abou Kanani, with extremely low and high linoleic acid contents, respectively. Subsequently, these two cultivars were used to investigate the specific contribution of different fatty acid desaturases to the linoleic acid content of mesocarp tissue during olive fruit development and ripening. Fatty acid desaturase gene expression levels, together with lipid analysis, suggest that not only OeFAD2-2 and OeFAD2-5 but also the different specificities of extraplastidial acyltransferase enzymes are responsible for the variability of the oleic/linoleic acid ratio in olive cultivars. All this information allows for an advancement in the knowledge of the linoleic acid biosynthesis in different olive cultivars, which can impact olive breeding programs to improve olive oil quality. [ABSTRACT FROM AUTHOR]

Winter turnip rape (Brassica rapa L.) is an important overwintering oil crop that is widely planted in northwestern China. It considered to be a good genetic resource for cold-tolerant research because its roots can survive harsh winter conditions. Here, we performed comparative transcriptomics analysis of the roots of two winter turnip rape varieties, Longyou7 (L7, strong cold tolerance) and Tianyou2 (T2, low cold tolerance), under normal condition (CK) and cold stress (CT) condition. A total of 8,366 differentially expressed genes (DEGs) were detected between the two L7 root groups (L7CK_VS_L7CT), and 8,106 DEGs were detected for T2CK_VS_T2CT. Among the DEGs, two ω-3 fatty acid desaturase (FAD3), two delta-9 acyl-lipid desaturase 2 (ADS2), one diacylglycerol kinase (DGK), and one 3-ketoacyl-CoA synthase 2 (KCS2) were differentially expressed in the two varieties and identified to be related to fatty acid synthesis. Four glutamine synthetase cytosolic isozymes (GLN), serine acetyltransferase 1 (SAT1), and serine acetyltransferase 3 (SAT3) were down-regulated under cold stress, while S-adenosylmethionine decarboxylase proenzyme 1 (AMD1) had an up-regulation tendency in response to cold stress in the two samples. Moreover, the delta-1-pyrroline-5-carboxylate synthase (P5CS), δ-ornithine aminotransferase (δ-OAT), alanine-glyoxylate transaminase (AGXT), branched-chain-amino-acid transaminase (ilvE), alpha-aminoadipic semialdehyde synthase (AASS), Tyrosine aminotransferase (TAT) and arginine decarboxylase related to amino acid metabolism were identified in two cultivars variously expressed under cold stress. The above DEGs related to amino acid metabolism were suspected to the reason for amino acids content change. The RNA-seq data were validated by real-time quantitative RT-PCR of 19 randomly selected genes. The findings of our study provide the gene expression profile between two varieties of winter turnip rape, which lay the foundation for a deeper understanding of the highly complex regulatory mechanisms in plants during cold treatment. [ABSTRACT FROM AUTHOR]

Background: The macrophage‐activating lipopeptide‐2 (MALP‐2) activates cells carrying a functional Toll‐like receptor (TLR)‐2/6. Human sebocytes express functional TLR‐2, TLR‐4 and CD14. Upregulation of stearoyl‐CoA desaturase (SCD) and fatty acid desaturase‐2 (FADS2) expression induces pro‐inflammatory sebaceous activity. On the other hand, corticotropin‐releasing hormone (CRH) is likely to serve as an autocrine stress hormone in human sebocytes. In addition to its antiproliferative, lipogenetic and androgen‐activating functions, CRH exhibits a pro‐inflammatory action and its expression is upregulated in acne‐involved sebaceous glands. Objective: Determination of the pro‐inflammatory function of MALP‐2 and CRH and clarification of the option that MALP‐2 and/or CRH activity on human sebocytes might be mediated through SCD and/or FADS2. Methods: SZ95 sebocytes were treated with MALP‐2, CRH and the SCD inhibitor/ligand FPCA. SCD, FADS2, TLR‐2 mRNA and protein levels and IL‐6 and IL‐8 secretion were investigated. Intracellular CRH levels were assessed under treatment with CRH, MALP‐2, linoleic acid and arachidonic acid. Phorbol 12‐myristate 13‐acetate and dexamethasone served as positive and negative controls, respectively. Results: MALP‐2 upregulated SCD, FADS2, TLR‐2 mRNA and protein levels and IL‐6 and IL‐8 secretion from SZ95 sebocytes. Co‐incubation of SZ95 sebocytes with MALP‐2/FPCA did not affect the MALP‐2‐induced SCD mRNA upregulation but reduced FADS2 mRNA levels and inhibited IL‐8 secretion. CRH induced an early, low‐level SCD and FADS2 upregulation and TLR‐2 and IL‐8 secretion. High intracellular CRH concentrations could be detected early after CRH treatment and persisted up to 24 h. MALP‐2 stimulated intracellular CRH levels. Conclusions: MALP‐2 stimulates the inflammatory signalling in human sebocytes through SCD and FADS2 activation. Inhibition of FADS2 mRNA levels and IL‐8 secretion through MALP‐2/FCPA co‐incubation and diminution of fatty acid unsaturation might lead to a reduction of pro‐inflammatory sebaceous lipids. CRH upregulates inflammatory signalling via the SCD/FADS2 pathway, and MALP‐2 selectively enhances CRH levels in human sebocytes. [ABSTRACT FROM AUTHOR]

An 8‐week growth trial was conducted to evaluate effects of dietary oil sources on growth, enzymes activity and genes expression levels related to lipid metabolism of hybrid grouper (♀Epinephelus fuscoguttatus × ♂E. lanceolatu) juveniles. Seven iso‐lipid (97 g/kg of dry matter) and iso‐protein (503.5 g/kg of dry matter) experimental diets were formulated containing 50 g/kg fish oil (FO; acting as controls) or various vegetable oils (VOs): corn oil (CO), sunflower oil (SO), tea oil (TO), olive oil (OO), rice oil (RO) and mixed oil (MO; comprising equal amounts of these oils). Each diet was fed to triplicate groups of 40 fish for per repetition (15.09 ± 0.01 g) for 56 days. The results show that (a) alternative dietary oils had no significant effects on final weight compared with control group (p >.05); (b) compared with FO group, VOs significantly changed the contents of serum lipoproteins, cholesterol, triglycerides and the activity of liver lipid‐metabolizing enzymes (p <.05); (c) CO group had the least effect on the serum lipoproteins, triglycerides and cholesterol of grouper compared with control; the activity of liver lipid‐metabolizing enzymes in RO and control group was the closest; (d) the mRNA levels of Δ6 Fatty acid desaturase (Δ6Fad), hormone‐sensitive lipase (HSL) and lipoprotein lipase (LPL) were not significantly effected by lipid sources, but CO, TO, OO and MO significantly down‐regulated the expression of fatty acid synthetase (FAS) mRNA level in liver, while RO opposite (p <.05); (e) vegetable oil significantly up‐regulated peroxisome proliferator‐activated receptor α (PPARα) and peroxisome proliferator‐activated receptor β (PPARβ) mRNA levels, while TO and RO down‐regulated peroxisome proliferator‐activated receptor γ (PPARγ) mRNA levels (p <.05); and 6) MO significantly increased the mRNA levels of heart‐type fatty acid‐binding protein (H‐FABP) and adipocyte‐type fatty acid‐binding protein (A‐FABP) (p <.05), while other VOs had no effect on them (p >.05). In conclusion, dietary substitution of FO by VO in diet affected lipid metabolism of grouper, which may be regulated by PPARs. [ABSTRACT FROM AUTHOR]

The Channel catfish is one of the most important freshwater fish species in North America. Conventionally their selection for genetic improvement is focused in growth related traits but not on quality traits as flavor and fatty acid deposition. The aim of this study was the sequencing of Stearoyl‐CoA Desaturase (SCD) and Fatty Acid Desaturase 2 (FADS2) genes, two of main genes in the biosynthesis of long chain polyunsaturated fatty acids, for novel variation discovering as a preliminary of marker assisted broader assessment. In SCD gene, two novel synonym polymorphisms (Exon 1 and 3) and a non‐synonymous Serine coding polymorphism in exon 3, were found. In FADS2, two synonymous polymorphisms (Exon 1 and 3) and multiple polymorphisms in non‐coding regions were discovered. Further association analysis of these novel variations could reveal punctual effect on fatty acid deposition traits and their utility for marker assisted selection purposes. [ABSTRACT FROM AUTHOR]

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Background: Fruit ripening in Prunus persica melting varieties involves several physiological changes that have a direct impact on the fruit organoleptic quality and storage potential. By studying the proteomic differences between the mesocarp of mature and ripe fruit, it would be possible to highlight critical molecular processes involved in the fruit ripening. Results: To accomplish this goal, the proteome from mature and ripe fruit was assessed from the variety O'Henry through shotgun proteomics using 1D-gel (PAGE-SDS) as fractionation method followed by LC/MS-MS analysis. Data from the 131,435 spectra could be matched to 2740 proteins, using the peach genome reference v1. After data pre-treatment, 1663 proteins could be used for comparison with datasets assessed using transcriptomic approaches and for quantitative protein accumulation analysis. Close to 26% of the genes that code for the proteins assessed displayed higher expression at ripe fruit compared to other fruit developmental stages, based on published transcriptomic data. Differential accumulation analysis between mature and ripe fruit revealed that 15% of the proteins identified were modulated by the ripening process, with glycogen and isocitrate metabolism, and protein localization overrepresented in mature fruit, as well as cell wall modification in ripe fruit. Potential biomarkers for the ripening process, due to their differential accumulation and gene expression pattern, included a pectin methylesterase inhibitor, a gibbellerin 2-beta-dioxygenase, an omega-6 fatty acid desaturase, a homeobox-leucine zipper protein and an ACC oxidase. Transcription factors enriched in NAC and Myb protein domains would target preferentially the genes encoding proteins more abundant in mature and ripe fruit, respectively. Conclusions: Shotgun proteomics is an unbiased approach to get deeper into the proteome allowing to detect differences in protein abundance between samples. This technique provided a resolution so that individual gene products could be identified. Many proteins likely involved in cell wall and sugar metabolism, aroma and color, change their abundance during the transition from mature to ripe fruit. [ABSTRACT FROM AUTHOR]

Summary: Forest fires generate a large amount of carbon that remains resident on the site as dead and partially 'pyrolysed' (i.e. burnt) material that has long residency times and constitutes a significant pool in fire‐prone ecosystems. In addition, fire‐induced hydrophobic soil layers, caused by condensation of pyrolysed waxes and lipids, increase post‐fire erosion and can lead to long‐term productivity losses. A small set of pyrophilous fungi dominate post‐fire soils and are likely to be involved with the degradation of all these compounds, yet almost nothing is currently known about what these fungi do or the metabolic processes they employ. In this study, we sequenced and analysed genomes from fungi isolated after Rim fire near Yosemite National Park in 2013 and showed the enrichment/expansion of CAZymes and families known to be involved in fruiting body initiation when compared to other basidiomycete fungi. We found gene families potentially involved in the degradation of the hydrophobic layer and pyrolysed organic matter, such as hydrophobic surface binding proteins, laccases (AA1_1), xylanases (GH10, GH11), fatty acid desaturases and tannases. Thus, pyrophilous fungi are important actors to restate the soil's functional capabilities. [ABSTRACT FROM AUTHOR]