Search Results (41)

Sea buckthorn is a vital woody oil species valued for its role in soil conservation and its bioactive seed oil, which is rich in unsaturated fatty acids and other compounds. However, low seed oil content and small seed size are the main bottlenecks restricting the development and utilization of sea buckthorn. In this study, we tested the seed oil content and seed size of 12 sea buckthorn cultivars and identified the key genes and transcription factors involved in seed development and lipid biosynthesis via the integration of UID RNA-seq (Unique Identifiers, UID), WGCNA (weighted gene co-expression network analysis) and qRT-PCR (quantitative real-time PCR) analysis. The results revealed five cultivars (CY02, CY11, CY201309, CY18, CY21) with significantly higher oil contents and five cultivars (CY10, CY201309, CY18, CY21, CY27) with significantly heavier seeds. A total of 10,873 genes were significantly differentially expressed between the S1 and S2 seed developmental stages of the 12 cultivars. WGCNA was used to identify five modules related to seed oil content and seed weight/size, and 417 candidate genes were screened from these modules. Among them, multiple hub genes and transcription factors were identified; for instance, ATP synthase, ATP synthase subunit D and Acyl carrier protein 1 were related to seed development; plastid–lipid-associated protein, acyltransferase-like protein, and glycerol-3-phosphate 2-O-acyltransferase 6 were involved in lipid biosynthesis; and transcription factors DOF1.2, BHLH137 and ERF4 were associated with seed enlargement and development. These findings provide crucial insights into the genetic regulation of seed traits in sea buckthorn, offering targets for future breeding efforts aimed at improving oil yield and quality. Full article

Sunflower is one of the four most important oilseed crops in the world, and its edible oil is of high nutritional quality. However, the molecular regulatory mechanism of oil accumulation in sunflowers is still unclear. In this study, we selected two inbred lines with significant differences in oleic acid content and similar agronomic traits: the high oleic acid content (82.5%) inbred line 227 and the low oleic acid content (30.8%) inbred line 228. Sunflower seeds were selected for transcriptome experiments at 10, 20, and 30 days after full bloom (DAFB). There were 21, 225, and 632 differentially expressed genes (DEGs) identified at the three times, respectively. The Gene Ontology (GO) analysis showed that DEGs from two sunflower cultivars at three stages were significantly enriched in the activities of omega-6 fatty acid desaturase and glucosyltransferase. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis found that at 10, 20, and 30 DAFB, DEGs were significantly enriched in the unsaturated fatty acid synthesis pathway, glutathione metabolism pathway, and pyruvate metabolism pathway. Through mapping analysis of GO in the KEGG pathway, it was found that the omega-6 fatty acid desaturase gene FAD6/FAD2, diacylglyceroyltransferase gene DGAT, glycerol-3-phosphate acyltransferase gene GPAT, and long-chain acyl-CoA synthase gene LACS may play important roles in regulating sunflower oleic acid content. Our research provides candidate genes and a research basis for breeding high oleic sunflowers. Full article

Glycerol-3-phosphate acyltransferase (GPAT), as a rate-limiting enzyme engaged in lipid synthesis pathways, exerts an important role in plant growth and development as well as environmental adaptation throughout diverse growth stages. Alfalfa (Medicago sativa L.) is one of the most significant leguminous forages globally; however, its growth process is frequently exposed to environmental stress, giving rise to issues such as impeded growth and decreased yield. At present, the comprehension of the GPAT genes in alfalfa and their reactions to abiotic stresses is conspicuously deficient. This study identified 15 GPATs from the genome of “Zhongmu No. 1” alfalfa, which were phylogenetically categorized into three major groups (Groups I ~ III). Furthermore, Group III is further subdivided into three distinct subgroups. MsGPATs belonging to the same subfamily exhibited similar protein conserved motifs and gene structural characteristics, in which groups with simple conserved motifs had more complex gene structures. A multitude of regulatory cis-elements pertinent to hormones and responses to environmental stress were detected in their promoter regions. In addition, a spatial–temporal expression analysis showed that MsGPATs have significant tissue specificity. Furthermore, the transcriptomic analysis of ABA treatment and the qRT-PCR results under drought, salt, and cold stress demonstrated that the majority of MsGPATs respond to abiotic stress with pronounced timely characteristics. It was also ascertained that these GPAT genes might assume a crucial role in salt and drought stress. This research can further constitute a fundamental basis for the exploration of the alfalfa GPAT family, the screening of key GPATs, and the investigation of their functionalities. Full article

Glycerol-3-phosphate acyltransferase (GPAT) genes encode enzymes involved in the biosynthesis of plant oils. Rapeseed has four BnGPAT9 genes, but the expression patterns and functions of these four homologous copies in rapeseed for seed oil accumulation are not well understood. In this study, we cloned the four BnGPAT9 genes and their promoters from Brassica napus and found significant differences in the expression of BnGPAT9 genes among different rapeseed varieties. We confirmed that BnGPAT9-A01/C01 are highly conserved in rapeseed, with high expression levels in various tissues, especially during the late stages of silique development and seed maturation. All four BnGPAT9 genes (BnGPAT9-A01/C01/A10/C09) can promote seed oil accumulation, but BnGPAT9-A01/C01 have a greater effect. Overexpression in Arabidopsis and rapeseed increased seed oil content and altered fatty acid composition, significantly increasing linolenic acid content. Transcriptome analysis revealed that BnGPAT9 genes promote the upregulation of genes related to oil synthesis, particularly those in the Plant–pathogen interaction, alpha-Linolenic acid metabolism, MAPK signaling pathway—plant, and Glutathione metabolism pathways. In summary, these results indicate that the four BnGPAT9 genes in rapeseed have different expression patterns and roles in regulating seed oil accumulation, with BnGPAT9-A01/C01 contributing the most to promoting oil accumulation. Full article

Glycerol-3-phosphoacyltransferase (GPAT) is an important rate-limiting enzyme in the biosynthesis of triacylglycerol (TAG), which is of great significance for plant growth, development, and response to abiotic stress. Although the characteristics of GPAT have been studied in many model plants, little is known about its expression profile and function in barley, especially under abiotic stress. In this study, 22 GPAT genes were identified in the barley genome and divided into three groups (I, II, III), with the latter Group III subdivided further into three subgroups based on the phylogenetic analysis. The analyses of conserved motifs, gene structures, and the three-dimensional structure of HvGPAT proteins also support this classification. Through evolutionary analysis, we determined that HvGPATs in Group I were the earliest to diverge during 268.65 MYA, and the differentiation of other HvGPATs emerged during 86.83–169.84 MYA. The tissue expression profile showed that 22 HvGPAT genes were almost not expressed in INF1 (inflorescence 1). Many functional elements related to stress responses and hormones in cis-element analysis, as well as qRT-PCR results, confirm that these HvGPAT genes were involved in abiotic stress responses. The expression level of HvGPAT18 was significantly increased under abiotic stress and its subcellular localization indicated its function in the endoplasmic reticulum. Various physiological traits under abiotic stress were evaluated using transgenic Arabidopsis to gain further insight into the role of HvGPAT18, and it was found that transgenic seedlings have stronger resistance under abiotic stress than to the wild-type (WT) plants. Overall, our results provide new insights into the evolution and function of the barley GPAT gene family and enable us to explore the molecular mechanism of functional diversity behind the evolutionary history of these genes. Full article

This review delves into the enzymatic processes governing the initial stages of glycerophospholipid (phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine) and triacylglycerol synthesis. The key enzymes under scrutiny include GPAT and AGPAT. Additionally, as most AGPATs exhibit LPLAT activity, enzymes participating in the Lands cycle with similar functions are also covered. The review begins by discussing the properties of these enzymes, emphasizing their specificity in enzymatic reactions, notably the incorporation of polyunsaturated fatty acids (PUFAs) such as arachidonic acid and docosahexaenoic acid (DHA) into phospholipids. The paper sheds light on the intricate involvement of these enzymes in various diseases, including obesity, insulin resistance, and cancer. To underscore the relevance of these enzymes in cancer processes, a bioinformatics analysis was conducted. The expression levels of the described enzymes were correlated with the overall survival of patients across 33 different types of cancer using the GEPIA portal. This review further explores the potential therapeutic implications of inhibiting these enzymes in the treatment of metabolic diseases and cancer. By elucidating the intricate enzymatic pathways involved in lipid synthesis and their impact on various pathological conditions, this paper contributes to a comprehensive understanding of these processes and their potential as therapeutic targets. Full article

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first step in triacylglycerol synthesis. Understanding its substrate recognition mechanism may help to design drugs to regulate the production of glycerol lipids in cells. In this work, we investigate how the native substrate, glycerol-3-phosphate (G3P), and palmitoyl-coenzyme A (CoA) bind to the human GPAT isoform GPAT4 via molecular dynamics simulations (MD). As no experimentally resolved GPAT4 structure is available, the AlphaFold model is employed to construct the GPAT4–substrate complex model. Using another isoform, GPAT1, we demonstrate that once the ligand binding is properly addressed, the AlphaFold complex model can deliver similar results to the experimentally resolved structure in MD simulations. Following the validated protocol of complex construction, we perform MD simulations using the GPAT4–substrate complex. Our simulations reveal that R427 is an important residue in recognizing G3P via a stable salt bridge, but its motion can bring the ligand to different binding hotspots on GPAT4. Such high flexibility can be attributed to the flexible region that exists only on GPAT4 and not on GPAT1. Our study reveals the substrate recognition mechanism of GPAT4 and hence paves the way towards designing GPAT4 inhibitors. Full article

Glycerol-3-phosphate acyltransferase GPAT9 catalyzes the first acylation of glycerol-3-phosphate (G3P), a committed step of glycerolipid synthesis in Arabidopsis. The role of GPAT9 in Brassica napus remains to be elucidated. Here, we identified four orthologs of GPAT9 and found that BnaGPAT9 encoded by BnaC01T0014600WE is a predominant isoform and promotes seed oil accumulation and eukaryotic galactolipid synthesis in Brassica napus. BnaGPAT9 is highly expressed in developing seeds and is localized in the endoplasmic reticulum (ER). Ectopic expression of BnaGPAT9 in E. coli and siliques of Brassica napus enhanced phosphatidic acid (PA) production. Overexpression of BnaGPAT9 enhanced seed oil accumulation resulting from increased 18:2-fatty acid. Lipid profiling in developing seeds showed that overexpression of BnaGPAT9 led to decreased phosphatidylcholine (PC) and a corresponding increase in phosphatidylethanolamine (PE), implying that BnaGPAT9 promotes PC flux to storage triacylglycerol (TAG). Furthermore, overexpression of BnaGPAT9 also enhanced eukaryotic galactolipids including monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), with increased 36:6-MGDG and 36:6-DGDG, and decreased 34:6-MGDG in developing seeds. Collectively, these results suggest that ER-localized BnaGPAT9 promotes PA production, thereby enhancing seed oil accumulation and eukaryotic galactolipid biosynthesis in Brassica napus. Full article

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first step in triacylglycerol (TAG) biosynthesis. However, GPAT members and their functions remain poorly understood in Perilla frutescens, a special edible-medicinal plant with its seed oil rich in polyunsaturated fatty acids (mostly α-linolenic acid, ALA). Here, 14 PfGPATs were identified from the P. frutescens genome and classified into three distinct groups according to their phylogenetic relationships. These 14 PfGPAT genes were distributed unevenly across 11 chromosomes. PfGPAT members within the same subfamily had highly conserved gene structures and four signature functional domains, despite considerable variations detected in these conserved motifs between groups. RNA-seq and RT-qPCR combined with dynamic analysis of oil and FA profiles during seed development indicated that PfGPAT9 may play a crucial role in the biosynthesis and accumulation of seed oil and PUFAs. Ex vivo enzymatic assay using the yeast expression system evidenced that PfGPAT9 had a strong GPAT enzyme activity crucial for TAG assembly and also a high substrate preference for oleic acid (OA, C18:1) and ALA (C18:3). Heterogeneous expression of PfGPAT9 significantly increased total oil and UFA (mostly C18:1 and C18:3) levels in both the seeds and leaves of the transgenic tobacco plants. Moreover, these transgenic tobacco lines exhibited no significant negative effect on other agronomic traits, including plant growth and seed germination rate, as well as other morphological and developmental properties. Collectively, our findings provide important insights into understanding PfGPAT functions, demonstrating that PfGPAT9 is the desirable target in metabolic engineering for increasing storage oil enriched with valuable FA profiles in oilseed crops. Full article

This study aimed to assess the impact of oleic acid (OA) supplementation on the biosynthesis of 10-hydroxy-2-decenoic acid (10-HDA) in Apis mellifera ligustica. In experiment 1, varying concentrations of OA (2%, 4%, 6% and 8%) were added to an artificial diet for newly emerged bees reared in cages. Analysis of 10-HDA content and gene expression in the mandibular gland (MG) revealed that the 8% OA treatment had the greatest impact on promoting the synthesis of 10-HDA. Subsequent investigations utilized RNA-seq and lipidomics to characterize the molecular signature in the MG after feeding the 8% OA diet. Phosphatidylcholine (PC) and triacylglycerol (TAG) were found to be the predominant lipids in the MG of worker bees. A total of 154 TAGs were identified, with TAG (18:1-18:1-18:1) exhibiting the highest abundance, which increased by 1.5 times. The major TAG species contained palmitic acid (16:0) and oleic acid (18:1) in their structure, which was associated with fatty acid composition of diet. The increase in abundance of main TAGs may be attributed to the upregulation of glycerol-3-phosphate acyltransferase (Gpat) and glycerol kinase (GK) gene expression at the transcriptional level. The upregulation of differentially expressed genes (DEGs) related to carbohydrate metabolism may contribute to meeting the heightened metabolic demands of the MGs in worker bees. Royal jelly (RJ) samples from bee colonies fed with the 8% OA diet exhibited higher 10-HDA level than RJ collected from bee colonies fed with the artificial diet. These results indicate that 8% OA addition in the diet enhanced biosynthesis of 10-HDA in the mandibular gland, which was accompanied by significant and highly species-selective remodeling of TAGs. Full article

Despite the importance of lipid metabolism in various biological processes, little is known about the functionality of ATS1, a plastid glycerol-3-phosphate acyltransferase catalyzing the initial step of the prokaryotic glycerolipids biosynthetic pathway, in plant response to salt stress. In this study, both the loss-of-function mutants and the overexpression lines of ATS1 were analyzed for salt tolerance properties. The results showed that ATS1 overexpression lines had lower seed germination, shoot biomass, chlorophyll content, the proportion of relatively normal pod, and higher root/shoot ratio and anthocyanidin content compared with the wild type. Physiological and biochemical analysis revealed that ats1 mutants had more unsaturated fatty acids to stabilize the plasma membrane under salt damage. Additionally, less induction of three main antioxidant enzymes activity and lower MDA content in ats1 mutants indicated that mutation of the ATS1 gene could reduce the damage extent. Furthermore, the ats1 mutants maintained the K⁺/Na⁺ homeostasis by upregulating HAK5 expression to increase K⁺ absorption and down-regulating HKT1 expression to prevent Na⁺ uptake. This study suggested that the ATS1 gene negatively affects salt resistance in Arabidopsis. Full article

One area of glioblastoma research is the metabolism of tumor cells and detecting differences between tumor and healthy brain tissue metabolism. Here, we review differences in fatty acid metabolism, with a particular focus on the biosynthesis of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) by fatty acid synthase (FASN), elongases, and desaturases. We also describe the significance of individual fatty acids in glioblastoma tumorigenesis, as well as the importance of glycerophospholipid and triacylglycerol synthesis in this process. Specifically, we show the significance and function of various isoforms of glycerol-3-phosphate acyltransferases (GPAT), 1-acylglycerol-3-phosphate O-acyltransferases (AGPAT), lipins, as well as enzymes involved in the synthesis of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), and cardiolipin (CL). This review also highlights the involvement of diacylglycerol O-acyltransferase (DGAT) in triacylglycerol biosynthesis. Due to significant gaps in knowledge, the GEPIA database was utilized to demonstrate the significance of individual enzymes in glioblastoma tumorigenesis. Finally, we also describe the significance of lipid droplets in glioblastoma and the impact of fatty acid synthesis, particularly docosahexaenoic acid (DHA), on cell membrane fluidity and signal transduction from the epidermal growth factor receptor (EGFR). Full article

Polygonatum rhizomes are rich in various compounds with many biological activities and are widely used in functional foods and pharmaceutical products. In order to screen for superior Polygonatum cyrtonema Hua (P. cyrtonema) germplasm and also to elucidate the nutritional and medicinal values of rhizomes, the metabolic composition and quality traits of rhizomes from different germplasms and age sections of P. cyrtonema were analysed by widely targeted metabolomics, and the molecular mechanism of triacylglycerol synthesis was explored. The results showed that the different germplasms and age sections of P. cyrtonema were rich in different nutritional and medicinal components. Of these, the broad-leaved green stem (GK) germplasm is rich in polysaccharides, alkaloids, and lipids; the pointed-leaved green stem (JL) germplasm is rich in flavonoids, steroids, and amino acids, while the pointed-leaved purple stem (JZ) germplasm contains more phenolic acids. The one-year (AT) age section is rich in polysaccharides, steroids, organic acids, and lipids; the three years (CT) age section contains more flavonoids, alkaloids, and amino acid metabolites. Lipids were significantly enriched in the broad-leaved green stem germplasm and the one-year age section. Interestingly, the highest accumulation of triacylglycerols, an important component of lipids, was also found in the GK germplasm and the AT age section. Nineteen, 14, and 13 members of the glycerol-3-phosphate acyltransferase (GPAT), lysophosphatidic acid acyltransferase (LPAT), and diacylglycerol acyltransferase (DGAT) gene families, respectively, involved in triacylglycerol synthesis were also identified. The quantitative real-time PCR (qRT-PCR) results further suggested that the differentially expressed PcDGAT1, PcDGAT2.4, PcGPAT9.1, PcLPAT2.9, and PcLPAT4.3 genes may play important roles in triacylglycerol synthesis in P. cyrtonema. Therefore, this study provides a new theoretical reference for product development and the breeding of new varieties of Polygonatum species. Full article

Zilpaterol hydrochloride (ZH) redistributes ingested energy and improves feed efficiency by increasing muscle mass and reducing fat in sheep and cattle carcasses in fattening; however, by increasing lipolysis and reducing intramuscular fat (IMF), it can affect meat quality in terms of the attributes of tenderness, juiciness, taste and color; in contrast, Zn methionine (ZM), due to its lipogenic effect, can improve meat marbling without affecting production efficiency. In the current study, 36 male Suffolk sheep were used (25 ± 0.58 kg live weight, LW) to evaluate the supply of ZH and ZM on growth, carcass traits, meat quality, fatty acid content and expression of genes which regulate the deposition of fatty acids (FA) in IMF. A completely randomized design was used, with factorial arrangement of 2 × 2 ZH (0 and 0.2 mg kg⁻¹ LW) and ZM (0 and 80 mg Zn kg⁻¹ dry matter, DM). The results showed that ZH increased (p < 0.05) carcass yield, compactness index and chop eye area and decreased greasing (p < 0.02). The content of ether extract in meat increased (p < 0.05) in sheep with ZM plus ZH, and in sheep with ZM (p < 0.01). ZH (p < 0.05) reduced (p < 0.02) the meat’s color index L*, a*, b*, C* and H*. The content in IMF of stearic (C18:0) and arachidic (C20:0) FA was reduced (p ≤ 0.05) by the effect of ZH, but the palmitoleic (C16:1), eicosatetraenoic (C20:4n6) and conjugated linoleic FA were increased (p ≤ 0.05) by the effect of ZH. ZM increased (p ≤ 0.05) palmitoleic (C16:1) and conjugated linoleic FA; the ZH interaction with ZM increased (p ≤ 0.05) linoleic (C18:2 c 9 c 12), linolenic (C18:3 c 9c12c15) and eicosatetraenoic (C20:4n6) FA. The ZH interaction with ZM influenced (p ≤ 0.05) the total saturated fatty acids (SFA), unsaturated fatty acids (UFA) and polyunsaturated fatty acids (PFA). ZH increased (p ≤ 0.05) the relative expression of mRNA from the enzymes lipoprotein lipase (LPL), hormone-sensitive lipase (HSL), glycerol -3-phosphate acyltransferase (GPAT1) and diglyceride acyltransferase (DGAT1). ZM increased (p ≤ 0.05) the relative expression of mRNA from the enzyme gene acetyl-CoA carboxylase (ACC) and HSL, monoglyceride lipase (MGL). The ZM interaction with ZH increased (p ≤ 0.05) the relative expression of mRNA genes of the enzymes HSL and ACC. It was concluded that ZH improved feed conversion (FC), increased yield and reduced fat in carcasses; ZM increased IMF in Longissimus dorsi. ZH and ZM influenced the FA composition, reduced the SFA and increased the UFA and PFA; both additives also influenced the relative mRNA expression of genes involved in fatty acid metabolism. Full article

MicroRNAs (miRNAs) are small RNA molecules consisting of approximately 22 nucleotides that are engaged in the regulation of various bio-processes. There is growing evidence that miR-29 is a key regulator of hepatic lipid metabolism. Mimics and inhibitors of bta-miRNA29d-3p were transiently transfected in bovine mammary epithelial cells (BMECs) to reveal the regulation of bta-miRNA29d-3p on lipid accumulation in BMECs. Results showed that overexpression of bta-miRNA29d-3p significantly inhibited the expression of genes related to triglyceride (TAG) synthesis, namely DGAT1 and mitochondrial glycerol-3-phosphate acyltransferase (GPAM, p < 0.01) and down-regulated TAG levels in cells (p < 0.05). The expression of fatty acid synthesis and desaturation-related genes FASN, SCD1, and ACACA, and transcription factor SREBF1 also decreased. Interference of bta-miRNA29d-3p significantly increased the expression of GPAM, DGAT1, FASN, SCD1, ACACA, and SREBF1 (p < 0.01), and significantly upregulated the concentration of TAG in cells. Furthermore, a luciferase reporter assay confirmed that GPAM is a direct target of bta-miRNA29d-3p. In summary, bta-miRNA29d-3p modulates fatty acid metabolism and TAG synthesis by regulating genes related to lipid metabolism in BMECs and targeting GPAM. Thus, bta-miRNA29d-3p plays an important role in controlling mammary lipid synthesis in cows. Full article