Disease Resistance against Magnaporthe grisea is Enhanced in Transgenic Rice with Suppression of  -3 Fatty Acid Desaturases

Fatty acids and their derivatives play important signaling roles in plant defense responses. It has been shown that suppressing a gene for stearoyl acyl carrier protein fatty-acid desaturase (SACPD) enhances the resistance of Arabidopsis (SSI2) and soybean to multiple pathogens. In this study, we present functional analyses of a rice homolog of SSI2 (OsSSI2) in disease resistance of rice plants. A transposon insertion mutation (Osssi2-Tos17) and RNAi-mediated knockdown of OsSSI2 (OsSSI2-kd) reduced the oleic acid (18:1) level and increased that of stearic acid (18:0), indicating that OsSSI2 is responsible for fatty-acid desaturase activity. These plants displayed spontaneous lesion formation in leaf blades, retarded growth, slight increase in endogenous free salicylic acid (SA) levels, and SA/benzothiadiazole (BTH)-specific inducible genes, including WRKY45, a key regulator of SA/BTH-induced resistance, in rice. Moreover, the OsSSI2-kd plants showed markedly enhanced resistance to the blast fungus Magnaporthe grisea and leaf-blight bacteria Xanthomonas oryzae pv. oryzae. These results suggest that OsSSI2 is involved in the negative regulation of defense responses in rice, as are its Arabidopsis and soybean counterparts. Microarray analyses identified 406 genes that were differentially expressed (≥2-fold) in OsSSI2-kd rice plants compared with wild-type rice and, of these, approximately 39% were BTH responsive. Taken together, our results suggest that induction of SA-responsive genes, including WRKY45, is likely responsible for enhanced disease resistance in OsSSI2-kd rice plants.

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Influence of plant fatty acid desaturases on plant-aphid interactions

10.1603/ice.2016.105519 ◽

2016 ◽

Author(s):

Fiona L. Goggin

Keyword(s):

Fatty Acid ◽

Fatty Acid Desaturases

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Presence or absence? Primary structure, regioselectivity and evolution of Δ12/ω3 fatty acid desaturases in nematodes

Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids ◽

10.1016/j.bbalip.2019.05.001 ◽

2019 ◽

Vol 1864 (9) ◽

pp. 1194-1205 ◽

Cited By ~ 2

Author(s):

Ralph Menzel ◽

Henrik von Chrzanowski ◽

Tina Tonat ◽

Kristina van Riswyck ◽

Patrick Schliesser ◽

...

Keyword(s):

Fatty Acid ◽

Primary Structure ◽

Fatty Acid Desaturases

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ChemInform Abstract: Synthesis of Inhibitors of Fatty Acid Desaturases

ChemInform ◽

10.1002/chin.199713262 ◽

2010 ◽

Vol 28 (13) ◽

pp. no-no

Author(s):

J. R. AL DULAYYMI ◽

M. S. BAIRD ◽

C. M. DALE ◽

B. GREHAN ◽

M. F. SHORTT ◽

...

Keyword(s):

Fatty Acid ◽

Fatty Acid Desaturases

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Cloning and expression analysis of three cDNAs encoding omega-3 fatty acid desaturases from Descurainia sophia

Biotechnology Letters ◽

10.1007/s10529-007-9391-9 ◽

2007 ◽

Vol 29 (9) ◽

pp. 1417-1424 ◽

Cited By ~ 10

Author(s):

Sanyuan Tang ◽

Rongzhan Guan ◽

Hongsheng Zhang ◽

Ji Huang

Keyword(s):

Fatty Acid ◽

Expression Analysis ◽

Cloning And Expression ◽

Omega 3 ◽

Fatty Acid Desaturases ◽

Omega 3 Fatty Acid ◽

Descurainia Sophia

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Saccharomyces kluyveri FAD3 encodes an ω3 fatty acid desaturase

Microbiology ◽

10.1099/mic.0.27049-0 ◽

2004 ◽

Vol 150 (6) ◽

pp. 1983-1990 ◽

Cited By ~ 34

Author(s):

Takahiro Oura ◽

Susumu Kajiwara

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Linoleic Acid ◽

Linolenic Acid ◽

Functional Characterization ◽

Fatty Acid Desaturase ◽

Fatty Acid Desaturases ◽

Desaturase Gene ◽

Saccharomyces Kluyveri ◽

Fatty Acid Desaturase Gene

Fungi, like plants, are capable of producing the 18-carbon polyunsaturated fatty acids linoleic acid and α-linolenic acid. These fatty acids are synthesized by catalytic reactions of Δ12 and ω3 fatty acid desaturases. This paper describes the first cloning and functional characterization of a yeast ω3 fatty acid desaturase gene. The deduced protein encoded by the Saccharomyces kluyveri FAD3 gene (Sk-FAD3) consists of 419 amino acids, and shows 30–60 % identity with Δ12 fatty acid desaturases of several eukaryotic organisms and 29–31 % identity with ω3 fatty acid desaturases of animals and plants. During Sk-FAD3 expression in Saccharomyces cerevisiae, α-linolenic acid accumulated only when linoleic acid was added to the culture medium. The disruption of Sk-FAD3 led to the disappearance of α-linolenic acid in S. kluyveri. These findings suggest that Sk-FAD3 is the only ω3 fatty acid desaturase gene in this yeast. Furthermore, transcriptional expression of Sk-FAD3 appears to be regulated by low-temperature stress in a manner different from the other fatty acid desaturase genes in S. kluyveri.

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Phytohormones Regulate the Non-Redundant Response of ω-3 Fatty Acid Desaturases to Low Temperatures in Chorispora Bungeana

10.21203/rs.3.rs-719872/v1 ◽

2021 ◽

Author(s):

Yulan Shi ◽

Sizhong Yang ◽

Xiule Yue ◽

Zhixing Zhao ◽

Lizhe An

Keyword(s):

Fatty Acids ◽

Abscisic Acid ◽

Fatty Acid ◽

Stress Response ◽

Low Temperatures ◽

Cultured Cells ◽

Temperature Decrease ◽

Fatty Acid Desaturases ◽

Cold Environments ◽

Chorispora Bungeana

Abstract To explore the contribution of ω-3 fatty acid desaturases (FADs) to cold stress response in a special cryophyte, Chorispora bungeana (C. bungeana), two plastidial ω-3 FAD genes (CbFAD7 and CbFAD8) were cloned and verified in a Arabidopsis fad7fad8 mutant, before being compared with the microsomal ω-3 FAD gene (CbFAD3) on expression profile. Though these genes were expressed in all tested tissues of C. bungeana, CbFAD7 and CbFAD8 have the highest expression in leaves, while CbFAD3 was mostly expressed in non-green tissues. Low temperatures (4, 0 and -4 ℃) resulted in significant increases in trienoic fatty acids (TAs, mainly C18:3), which were consistent with the non-redundant expression of CbFAD3 and CbFAD8 in suspension-cultured cells, and the coordination of CbFAD7 and CbFAD8 in leaves. Furthermore, the contribution of CbFAD8 increased as temperature decrease in the two tissues. Our data revealed that jasmonie acid and brassinosteroids participated in the cold-responsive expression of these genes in both tissues, and the pyhtohormone regulation in leaves was more complicated with the participation of abscisic acid and gibberellin. These results point to the hormone-regulated non-redundant contribution of ω-3 CbFADs to maintain appropriate level of TAs under low temperatures, which help C. bungeana survive in cold environments.

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SCD1/FADS2 fatty acid desaturases equipoise lipid metabolic activity and redox-driven ferroptosis in ascites-derived ovarian cancer cells

10.21203/rs.3.rs-1087508/v1 ◽

2021 ◽

Author(s):

Yang XUAN ◽

Mingo YUNG ◽

Fushun Chen ◽

Huogang WANG ◽

Wai-Sun CHAN ◽

...

Keyword(s):

Ovarian Cancer ◽

Fatty Acid ◽

Unsaturated Fatty Acids ◽

Malignant Ascites ◽

Peritoneal Metastases ◽

Ovarian Cancer Cells ◽

Platinum Resistance ◽

Fatty Acid Desaturases ◽

Genetic Ablation ◽

Metabolic Activities

Abstract Malignant ascites in peritoneal metastases is a lipid-enriched microenvironment and is frequently involved in the poor prognosis of epithelial ovarian cancer (EOC). However, the detailed mechanisms underlying ovarian cancer (OvCa) cells dictating their lipid metabolic activities in promoting tumor progression remain elusive. Here, we report that two critical fatty acid desaturases, stearoyl-CoA desaturase-1 (SCD1) and acyl-CoA 6-desaturase (FADS2), are aberrantly upregulated, accelerating lipid metabolic activities and tumor aggressiveness of ascites-derived OvCa cells. Lipidomic analysis revealed that the elevation of unsaturated fatty acids (UFAs) is positively associated with SCD1/FADS2 levels and the oncogenic capacities of OvCa cells. In contrast, pharmaceutical inhibition and genetic ablation of SCD1/FADS2 retarded tumor growth, suppressed cancer stem cell (CSC) formation and reduced platinum resistance in OvCa cells. Mechanistically, inhibition of SCD1/FADS2 directly downregulated GPX4 and the GSH/GSSG ratio, causing disruption of the cellular redox balance and subsequent iron-mediated lipid peroxidation in ascites-derived OvCa cells. Hence, combinational treatment with SCD1/FADS2 inhibitors and cisplatin synergistically repressed tumor cell dissemination, providing a promising chemotherapeutic strategy against EOC platinum resistance and peritoneal metastases.

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Transgenic Rice Expressing Isoflavone Synthase Gene from Soybean Shows Resistance against Blast Fungus (Magnaporthe oryzae)

Plant Disease ◽

10.1094/pdis-08-20-1777-re ◽

2021 ◽

Author(s):

Suresh Pokhrel ◽

Sathish K Ponniah ◽

Yulin Jia ◽

Oliver Yu ◽

Muthusamy Manoharan

Keyword(s):

Disease Resistance ◽

Transgenic Rice ◽

Magnaporthe Oryzae ◽

Plant Disease Resistance ◽

Rice Blast ◽

Plant Disease ◽

Plant Secondary Metabolites ◽

Single Copy ◽

Transgenic Lines ◽

Isoflavone Synthase

The isoflavones are a group of plant secondary metabolites primarily synthesized in legumes and are known for their role in improving human health and plant disease resistance. The isoflavones, especially genistein, act as precursors for the production of phytoalexins, which may induce broad-spectrum disease resistance in plants. In the present study, we screened transgenic rice lines expressing the isoflavone synthase (GmIFS1) gene from soybean for rice blast (Magnaporthe oryzae) resistance. Two homozygous transgenic lines (I2 and I10), based on single copy gene integration, were identified. The expression of GmIFS1 in transgenic lines was confirmed by qRT-PCR. Genistein was detected in the transgenic lines using LC-MS/MS. Subsequently, the transgenic lines were evaluated against the rice blast pathogen, isolate YJ54 (race IB-54). The results indicated that more than 60% of the plants in both the lines (I2 and I10) showed resistance against the blast pathogen. The progenies of one of the resistant transgenic lines (I10) also showed more than 65% resistance against rice blast. The resistance of these transgenic lines against rice blast may be attributed to the synthesis of isoflavone (genistein) in rice.

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