AIM:To compare the effect of vegetable oils on the uptake of lutein and zeaxanthin by adult retinal pigment epithelial(ARPE)-19 cells in vitro.METHODS:ARPE-19 cells were cultured in Dulbecco’s Modified Eagle Medium-F...AIM:To compare the effect of vegetable oils on the uptake of lutein and zeaxanthin by adult retinal pigment epithelial(ARPE)-19 cells in vitro.METHODS:ARPE-19 cells were cultured in Dulbecco’s Modified Eagle Medium-F-12 supplemented with 10%foetal bovine serum and 1%penicillin–streptomycin in a humidified 5%CO_(2) incubator maintained at 37℃.Cells were treated with 247μmol/L lutein,49μmol/L zeaxanthin and 1%(v/v)of either coconut oil,corn oil,peanut oil,olive oil,sunflower oil,soybean oil,castor oil,or linseed oil for 48h.Lutein and zeaxanthin concentration in the cells were quantified by high performance liquid chromatography.RESULTS:Among the oils tested,the highest lutein and zeaxanthin uptake was observed with coconut oil while the lowest was observed with linseed oil.CONCLUSION:ARPE-19 uptake of lutein and zeaxanthin are found to be dependent on the type of oils.展开更多
At present,the purification process of zeaxanthin mainly includes organic solvent extraction,ultrasonic-assisted extraction and enzyme extraction,and the content determination technology mainly includes ultraviolet-sp...At present,the purification process of zeaxanthin mainly includes organic solvent extraction,ultrasonic-assisted extraction and enzyme extraction,and the content determination technology mainly includes ultraviolet-spectrophotometry and high performance liquid chromatography.In this paper,the purification process and content determination technology of zeaxanthin in recent years are reviewed in order to provide ideas and theoretical basis for further research and application of zeaxanthin.展开更多
AIM: To compare serum Lutein and Zeaxanthin (L/Z) concentrations between patients with nonproliferative diabetic retinopathy (NDR) and normal subjects,and to explore the effect of L/Z supplementation on serum L/Z leve...AIM: To compare serum Lutein and Zeaxanthin (L/Z) concentrations between patients with nonproliferative diabetic retinopathy (NDR) and normal subjects,and to explore the effect of L/Z supplementation on serum L/Z level and visual function in NDR patients METHODS: Subjects were divided into three groups: 30 NDR patients supplied with Lutein 6mg/d and Zeaxanthin 0.5mg/d for three months (DR Group),30 NDR patients without L/Z supplementation (DR Control Group) and 30 normal subjects (Control Group).Serum L/Z concentrations were measured by liquid high-resolution chromatography (HPLC).Visual acuity was recorded at baseline,1 month,2 months and 3 months post initial supplementation.Serum L/Z concentration were measured at baseline,1 month and 2 months post initial supplementation.Contrast sensitivity (CS) and fovea thickness were recorded at baseline and 3 months post initial supplementation.RESULTS: Mean serum lutein concentrations in DR group were 0.0686±0.0296μg/mL and zeaxanthin concentration was 0.0137±0.0059μg/mL.The L/Z level of DR group was significantly lower compared to the control group( lutein: 0.2302±0.1308μg/mL,zeaxanthin: 0.0456±0.0266μg/m,P = 0.000).The concentration of lutein and zeaxanthin in the DR control group at base line was 0.0714±0.0357μg/mL and 0.0119±0.0072μg/mL,respectively.There was no significant change of L/Z concentration in the DR control group during the study.Serum L/Z concentrations of DR group increased significantly after supplementation(F=109.124,P=0.000;F=219.207,P=0.000).Visual acuity improved significantly after medication.Compared with pre-medication,the average CS values of 1.5cpd,3cpd and 6cpd after three months increased significantly (P =0.030,0.013,0.008) and the foveal thickness decreased.(P =0.05) CONCLUSION: Serum L/Z concentrations in DR patients are significantly lower than those in normal subjects,and L/Z intake can improve the visual acuity,CS and macular edema in DR patients,suggesting that L/Z supplementation might be targeted as potential potential therapeutic agents in treating NDR.展开更多
Zeaxanthin is a common carotenoid, which is a powerful antioxidant that protects against damage caused by reactive oxygen species. The aim of the present study was to investigate the effects of zeaxanthin supplementat...Zeaxanthin is a common carotenoid, which is a powerful antioxidant that protects against damage caused by reactive oxygen species. The aim of the present study was to investigate the effects of zeaxanthin supplementation on in vitro maturation of porcine embryo development. We investigated nuclear maturation, intracellular glutathione （GSH）, and reactive oxygen species （ROS） levels during in vitro maturation, and subsequent embryonic development following parthenogenetic activation and in vitro fertilization OVF）. The oocytes were maturated and used at the metaphase II stage. After 42 hours of in vitro maturation, the zeaxanthin-treated group （0.5 μmol/L） showed significant increases in nuclear maturation （89.6%） than the control group （83.4%） （P 〈 0.05）. The intracellular GSH levels increased significantly （P 〈 0.05） as zeaxanthin concentrations increased; ROS generation levels decreased with increased zeaxanthin concentrations, but there were no significant differences. There were no significant differences in subsequent embryonic development, cleavage rate, blastocyst stage rate, and total blastocyst cell numbers following parthenogenetic activation and IVF when in vitro maturation media was supplemented with zeaxanthin. These results suggest that treatment with zeaxanthin during in vitro maturation improved the nuclear maturation of porcine oocytes by increasing the intracellular GSH level, thereby slightly decreasing the intracellular ROS level.展开更多
As one of optical isomers of zeaxanthin, meso-zeaxanthin is an important ingredient of macular pigment. Compared with lutein and zeaxanthin, meso-zeaxanthin may display strong functions as antioxidant and filtering sh...As one of optical isomers of zeaxanthin, meso-zeaxanthin is an important ingredient of macular pigment. Compared with lutein and zeaxanthin, meso-zeaxanthin may display strong functions as antioxidant and filtering short-wavelength, for example, the blue light. Comparisons among lutein, zeaxanthin and meso-zeaxanthin as well as functions and distributions together with the source of meso-zeaxanthin were discussed. The application as a supplement of diet and issues should be studied in the future for mesozeaxanthin were also analyzed.展开更多
AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were iso...AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were isolated from cadaver and cultured in vitro. They were challenged with UVB radiation and H2 O2 with and without zeaxanthin pretreatment. Cell viability, p38 and c-JUN NH(2)-terminal kinase(JNK) phosphorylation, IL-6, IL-8 and MCP-1 secretion and malondialdehyde(MDA) content were measured.RESULTS: Zeaxanthin had no measurable cytotoxicity on limbal or conjunctival epithelial cells when used at concentrations of 5 μg/mL and below. At 30 mJ/cm2 UVB, the pretreatment of zeaxanthin increased the percentage of live cells from 50% to 69%(P=0.01) and from 66% to 75%(P=0.05) for limbal and conjunctival epithelial cells, respectively. The concentrations of IL-6, IL-8 and MCP-1 in the culture medium reduced to 66%(for IL-6 and MCP-1)and 56%(for IL-8) of the levels without zeaxanthin. This was accompanied by reduced p38 and JNK protein phosphorylation. Pretreatment of zeaxanthin also reduced intracellular MDA content caused by H2 O2 stimulation from 0.86 μmol/L to 0.52 μmol/L(P=0.02) in limbal epithelial cells and from 0.96 μmol/L to 0.56 μmol/L in conjunctival epithelial cells(P=0.03). However, zeaxanthin did nothave significant effect on H2 O2-induced cell death in limbal or conjunctival epithelial cells.CONCLUSION: Zeaxanthin is an effective reagent in reducing the detrimental effect of UV-radiation and oxidative stress on ocular surface epithelial cells.展开更多
AIM： To evaluate the efficacy of Goji berry supplementation on improving macular pigment, serum zeaxanthin levels and visual acuity in patients with early age-related macular degeneration （AMD）. METHODS： A total ...AIM： To evaluate the efficacy of Goji berry supplementation on improving macular pigment, serum zeaxanthin levels and visual acuity in patients with early age-related macular degeneration （AMD）. METHODS： A total of 114 patients （aged from 51 to 92y, mean age 69.53±8.41y） with early AMD were enrolled in our prospective, randomized controlled study. The included patients were assigned randomly to the Goji group （n=57） with 25 g of Goji berries supplementation per day for 90d and the control group （n=57） with their normal diet for 90d. Macular pigment optical density （MPOD） was measured using heterochromatic flicker photometry （HFP）. The levels of serum lutein （L）/zeaxanthin （Z） were analyzed using high-performance liquid chromatography （HPLC）. MPOD, serum L/Z levels and best corrected visual acuity （BCVA） were recorded at baseline and 90d. RESULTS： In the Goji group, there were no statistically significant differences in the serum L levels between the baseline （0.199±0.149 μmol/mL） and 90d （0.203±0.181 μmol/mL） （t=-0.186, P=0.850）; however the serum Z levels were increased at 90d （0.101±0.087 μmol/mL） compared with those at the baseline （0.029±0.032 μmol/mL） （t=6.412, P〈0.001）. Patients treated with Goji berry for 90d showed an elevated MPOD （0.877±0.202 DU） from the baseline （0.731±0.205 DU） （t=-4.741, P=0.000）. In contrast to the control group, the serum Z levels and MPOD were higher in the Goji group at 90d （both P〈0.05）. At 90d, patients with Goji berry supplementation had a relative decrease in BCVA （0.21±0.18 logMAR） compared with the baseline （0.27±0.20） （t=2.397, P=0.020）. CONCLUSION： Overall, daily supplementation with Goji berry for 90d improves MPOD by increasing serum Z levels rather than serum L levels in early AMD patients. Goji berry may be an effective therapeutic intervention for preventing the progression of early AMD.展开更多
From time immemorial, human beings have used pigments made from vegetables, fruits, superior plants, animal tissues and cereals. One of the greatest sources of pigments is the bacterium that, with the use of the moder...From time immemorial, human beings have used pigments made from vegetables, fruits, superior plants, animal tissues and cereals. One of the greatest sources of pigments is the bacterium that, with the use of the modern technology, has increased the production of metabolites of interest. The microbiological production of carotenoids has not been optimized to obtain pigment production quantities of pigments and carotenoids recovery that lower production costs. The aim of this work was to design a Zeaxanthin production process with Flavobacterium sp. immobilized cells in a fluidized bed bioreactor. An optimum culture medium for Zeaxanthin production in stirred flasks (2.46 g·L–1) was obtained. Furthermore, optimum process conditions for a maximum yield of Zeaxanthin production, by fluidized bed bioreactor, were established. A statistical analysis showed that the most significant factors were air flow, pH and NaCl concentration (4.5 g·L–1). In this study a maximum Zeaxanthin production of 3.8 g·L–1 was reached. The highest reported yield to date was 0.329 g·L–1.展开更多
Reducing losses caused by pathogens is an effective strategy for stabilizing crop yields.Daunting challenges remain in cloning and characterizing genes that inhibit stripe rust,a devastating disease of wheat(Triticum ...Reducing losses caused by pathogens is an effective strategy for stabilizing crop yields.Daunting challenges remain in cloning and characterizing genes that inhibit stripe rust,a devastating disease of wheat(Triticum aestivum)caused by Puccinia striiformis f.sp.tritici(Pst).We found that suppression of wheat zeaxanthin epoxidase 1(ZEP1)increased wheat defense against Pst.We isolated the yellow rust slower 1(yrs1)mutant of tetraploid wheat in which a premature stop mutation in ZEP1-B underpins the phenotype.Genetic analyses revealed increased H_(2)O_(2) accumulation in zep1 mutants and demonstrated a correlation between ZEP1 dysfunction and slower Pst growth in wheat.Moreover,wheat kinase START 1.1(WKS1.1,Yr36)bound,phosphorylated,and suppressed the biochemical activity of ZEP1.A rare natural allele in the hexaploid wheat ZEP1-B promoter reduced its transcription and Pst growth.Our study thus identified a novel suppressor of Pst,characterized its mechanism of action,and revealed beneficial variants for wheat disease control.This work opens the door to stacking wheat ZEP1 variants with other known Pst resistance genes in future breeding programs to enhance wheat tolerance to pathogens.展开更多
Carotenoids constitute a large group of natural pigments widely distributed in nature.These compounds not only provide fruits and flowers with distinctive colors,but also have significant health benefits for humans.Lu...Carotenoids constitute a large group of natural pigments widely distributed in nature.These compounds not only provide fruits and flowers with distinctive colors,but also have significant health benefits for humans.Lutein and zeaxanthin,both oxygen-containing carotenoids,are considered to play vital roles in promoting ocular development and maintaining eye health.However,humans and mammals cannot synthesize these carotenoid derivatives,which can only be taken from certain fruits or vegetables.Here,by introducing four endogenous synthetic genes,SlLCYE,SlLCYB,SlHYDB,and SlHYDE under fruit-specific promoters,we report the metabolic engineering of lutein/zeaxanthin biosynthesis in tomato fruit.Transgenic lines overexpression of one(SlLCYE),two(SlLCYE and SlLCYB;SlLCYB and SlHYDB),and all these four synthetic genes re-established the lutein/zeaxanthin biosynthetic pathways in the ripe tomato fruit and thus resulted in various types of carotenoid riched lines.Metabolic analyses of these engineered tomato fruits showed the strategy involved expression of SlLCYE tends to produceα-carotene and lutein,as well as a higher content of β-carotene and zeaxanthin was detected in lines overexpressing SlLCYB.In addition,the different combinations of engineered tomatoes with riched carotenoids showed higher antioxidant capacity and were associated with a significantly extended shelf life during postharvest storage.This work provides a successful example of accurate metabolic engineering in tomato fruit,suggesting the potential utility for synthetic biology to improve agronomic traits in crops.These biofortified tomato fruits could be also exploited as new research subjects for studying the health benefits of carotenoid derivatives.展开更多
文摘AIM:To compare the effect of vegetable oils on the uptake of lutein and zeaxanthin by adult retinal pigment epithelial(ARPE)-19 cells in vitro.METHODS:ARPE-19 cells were cultured in Dulbecco’s Modified Eagle Medium-F-12 supplemented with 10%foetal bovine serum and 1%penicillin–streptomycin in a humidified 5%CO_(2) incubator maintained at 37℃.Cells were treated with 247μmol/L lutein,49μmol/L zeaxanthin and 1%(v/v)of either coconut oil,corn oil,peanut oil,olive oil,sunflower oil,soybean oil,castor oil,or linseed oil for 48h.Lutein and zeaxanthin concentration in the cells were quantified by high performance liquid chromatography.RESULTS:Among the oils tested,the highest lutein and zeaxanthin uptake was observed with coconut oil while the lowest was observed with linseed oil.CONCLUSION:ARPE-19 uptake of lutein and zeaxanthin are found to be dependent on the type of oils.
基金Supported by Central Talent Training Fund Project for Local University Reform and Development(2020GSP16).
文摘At present,the purification process of zeaxanthin mainly includes organic solvent extraction,ultrasonic-assisted extraction and enzyme extraction,and the content determination technology mainly includes ultraviolet-spectrophotometry and high performance liquid chromatography.In this paper,the purification process and content determination technology of zeaxanthin in recent years are reviewed in order to provide ideas and theoretical basis for further research and application of zeaxanthin.
文摘AIM: To compare serum Lutein and Zeaxanthin (L/Z) concentrations between patients with nonproliferative diabetic retinopathy (NDR) and normal subjects,and to explore the effect of L/Z supplementation on serum L/Z level and visual function in NDR patients METHODS: Subjects were divided into three groups: 30 NDR patients supplied with Lutein 6mg/d and Zeaxanthin 0.5mg/d for three months (DR Group),30 NDR patients without L/Z supplementation (DR Control Group) and 30 normal subjects (Control Group).Serum L/Z concentrations were measured by liquid high-resolution chromatography (HPLC).Visual acuity was recorded at baseline,1 month,2 months and 3 months post initial supplementation.Serum L/Z concentration were measured at baseline,1 month and 2 months post initial supplementation.Contrast sensitivity (CS) and fovea thickness were recorded at baseline and 3 months post initial supplementation.RESULTS: Mean serum lutein concentrations in DR group were 0.0686±0.0296μg/mL and zeaxanthin concentration was 0.0137±0.0059μg/mL.The L/Z level of DR group was significantly lower compared to the control group( lutein: 0.2302±0.1308μg/mL,zeaxanthin: 0.0456±0.0266μg/m,P = 0.000).The concentration of lutein and zeaxanthin in the DR control group at base line was 0.0714±0.0357μg/mL and 0.0119±0.0072μg/mL,respectively.There was no significant change of L/Z concentration in the DR control group during the study.Serum L/Z concentrations of DR group increased significantly after supplementation(F=109.124,P=0.000;F=219.207,P=0.000).Visual acuity improved significantly after medication.Compared with pre-medication,the average CS values of 1.5cpd,3cpd and 6cpd after three months increased significantly (P =0.030,0.013,0.008) and the foveal thickness decreased.(P =0.05) CONCLUSION: Serum L/Z concentrations in DR patients are significantly lower than those in normal subjects,and L/Z intake can improve the visual acuity,CS and macular edema in DR patients,suggesting that L/Z supplementation might be targeted as potential potential therapeutic agents in treating NDR.
基金supported,in part,by a grant from the "National Research Foundation of Korea Grant funded by the Korean Government(NRF-2015H1D3A1066175)"the "Cooperative Research Program for Agriculture Science & Technology Development(Project No.PJ011288,PJ011077)" Rural Development Administration+1 种基金the "Ministry of Trade,Industry & Energy (MOTIE),Korea Institute for Advancement of Technology(KIAT) through the Leading Industry Development for Economic Region(Project No.R0004357)""Korea Institute of Planning and Evaluation for Technology in Food,Agriculture,Forestry and Fisheries (IPET) through Advanced Production Technology Development Program,funded by Ministry of Agriculture,Food and Rural Affairs(MAFRA)(Grant number: 115103-02)," Republic of Korea
文摘Zeaxanthin is a common carotenoid, which is a powerful antioxidant that protects against damage caused by reactive oxygen species. The aim of the present study was to investigate the effects of zeaxanthin supplementation on in vitro maturation of porcine embryo development. We investigated nuclear maturation, intracellular glutathione （GSH）, and reactive oxygen species （ROS） levels during in vitro maturation, and subsequent embryonic development following parthenogenetic activation and in vitro fertilization OVF）. The oocytes were maturated and used at the metaphase II stage. After 42 hours of in vitro maturation, the zeaxanthin-treated group （0.5 μmol/L） showed significant increases in nuclear maturation （89.6%） than the control group （83.4%） （P 〈 0.05）. The intracellular GSH levels increased significantly （P 〈 0.05） as zeaxanthin concentrations increased; ROS generation levels decreased with increased zeaxanthin concentrations, but there were no significant differences. There were no significant differences in subsequent embryonic development, cleavage rate, blastocyst stage rate, and total blastocyst cell numbers following parthenogenetic activation and IVF when in vitro maturation media was supplemented with zeaxanthin. These results suggest that treatment with zeaxanthin during in vitro maturation improved the nuclear maturation of porcine oocytes by increasing the intracellular GSH level, thereby slightly decreasing the intracellular ROS level.
文摘As one of optical isomers of zeaxanthin, meso-zeaxanthin is an important ingredient of macular pigment. Compared with lutein and zeaxanthin, meso-zeaxanthin may display strong functions as antioxidant and filtering short-wavelength, for example, the blue light. Comparisons among lutein, zeaxanthin and meso-zeaxanthin as well as functions and distributions together with the source of meso-zeaxanthin were discussed. The application as a supplement of diet and issues should be studied in the future for mesozeaxanthin were also analyzed.
基金Supported by the National Natural Science Foundation of China(No.81570829)
文摘AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were isolated from cadaver and cultured in vitro. They were challenged with UVB radiation and H2 O2 with and without zeaxanthin pretreatment. Cell viability, p38 and c-JUN NH(2)-terminal kinase(JNK) phosphorylation, IL-6, IL-8 and MCP-1 secretion and malondialdehyde(MDA) content were measured.RESULTS: Zeaxanthin had no measurable cytotoxicity on limbal or conjunctival epithelial cells when used at concentrations of 5 μg/mL and below. At 30 mJ/cm2 UVB, the pretreatment of zeaxanthin increased the percentage of live cells from 50% to 69%(P=0.01) and from 66% to 75%(P=0.05) for limbal and conjunctival epithelial cells, respectively. The concentrations of IL-6, IL-8 and MCP-1 in the culture medium reduced to 66%(for IL-6 and MCP-1)and 56%(for IL-8) of the levels without zeaxanthin. This was accompanied by reduced p38 and JNK protein phosphorylation. Pretreatment of zeaxanthin also reduced intracellular MDA content caused by H2 O2 stimulation from 0.86 μmol/L to 0.52 μmol/L(P=0.02) in limbal epithelial cells and from 0.96 μmol/L to 0.56 μmol/L in conjunctival epithelial cells(P=0.03). However, zeaxanthin did nothave significant effect on H2 O2-induced cell death in limbal or conjunctival epithelial cells.CONCLUSION: Zeaxanthin is an effective reagent in reducing the detrimental effect of UV-radiation and oxidative stress on ocular surface epithelial cells.
基金Supported by Special Foundation for Public Welfare Research of China(No.2013CZ-9)
文摘AIM： To evaluate the efficacy of Goji berry supplementation on improving macular pigment, serum zeaxanthin levels and visual acuity in patients with early age-related macular degeneration （AMD）. METHODS： A total of 114 patients （aged from 51 to 92y, mean age 69.53±8.41y） with early AMD were enrolled in our prospective, randomized controlled study. The included patients were assigned randomly to the Goji group （n=57） with 25 g of Goji berries supplementation per day for 90d and the control group （n=57） with their normal diet for 90d. Macular pigment optical density （MPOD） was measured using heterochromatic flicker photometry （HFP）. The levels of serum lutein （L）/zeaxanthin （Z） were analyzed using high-performance liquid chromatography （HPLC）. MPOD, serum L/Z levels and best corrected visual acuity （BCVA） were recorded at baseline and 90d. RESULTS： In the Goji group, there were no statistically significant differences in the serum L levels between the baseline （0.199±0.149 μmol/mL） and 90d （0.203±0.181 μmol/mL） （t=-0.186, P=0.850）; however the serum Z levels were increased at 90d （0.101±0.087 μmol/mL） compared with those at the baseline （0.029±0.032 μmol/mL） （t=6.412, P〈0.001）. Patients treated with Goji berry for 90d showed an elevated MPOD （0.877±0.202 DU） from the baseline （0.731±0.205 DU） （t=-4.741, P=0.000）. In contrast to the control group, the serum Z levels and MPOD were higher in the Goji group at 90d （both P〈0.05）. At 90d, patients with Goji berry supplementation had a relative decrease in BCVA （0.21±0.18 logMAR） compared with the baseline （0.27±0.20） （t=2.397, P=0.020）. CONCLUSION： Overall, daily supplementation with Goji berry for 90d improves MPOD by increasing serum Z levels rather than serum L levels in early AMD patients. Goji berry may be an effective therapeutic intervention for preventing the progression of early AMD.
文摘From time immemorial, human beings have used pigments made from vegetables, fruits, superior plants, animal tissues and cereals. One of the greatest sources of pigments is the bacterium that, with the use of the modern technology, has increased the production of metabolites of interest. The microbiological production of carotenoids has not been optimized to obtain pigment production quantities of pigments and carotenoids recovery that lower production costs. The aim of this work was to design a Zeaxanthin production process with Flavobacterium sp. immobilized cells in a fluidized bed bioreactor. An optimum culture medium for Zeaxanthin production in stirred flasks (2.46 g·L–1) was obtained. Furthermore, optimum process conditions for a maximum yield of Zeaxanthin production, by fluidized bed bioreactor, were established. A statistical analysis showed that the most significant factors were air flow, pH and NaCl concentration (4.5 g·L–1). In this study a maximum Zeaxanthin production of 3.8 g·L–1 was reached. The highest reported yield to date was 0.329 g·L–1.
基金supported by the National Key Research and Development Program(2022YFF1001501)the National Natural Science Foundation of China(31972350)+1 种基金the Chinese Universities Scientific Fund(2022TC174)the financial support from an open project of the State Key Laboratory of Crop Stress Adaptation and Improvement in Henan University.
文摘Reducing losses caused by pathogens is an effective strategy for stabilizing crop yields.Daunting challenges remain in cloning and characterizing genes that inhibit stripe rust,a devastating disease of wheat(Triticum aestivum)caused by Puccinia striiformis f.sp.tritici(Pst).We found that suppression of wheat zeaxanthin epoxidase 1(ZEP1)increased wheat defense against Pst.We isolated the yellow rust slower 1(yrs1)mutant of tetraploid wheat in which a premature stop mutation in ZEP1-B underpins the phenotype.Genetic analyses revealed increased H_(2)O_(2) accumulation in zep1 mutants and demonstrated a correlation between ZEP1 dysfunction and slower Pst growth in wheat.Moreover,wheat kinase START 1.1(WKS1.1,Yr36)bound,phosphorylated,and suppressed the biochemical activity of ZEP1.A rare natural allele in the hexaploid wheat ZEP1-B promoter reduced its transcription and Pst growth.Our study thus identified a novel suppressor of Pst,characterized its mechanism of action,and revealed beneficial variants for wheat disease control.This work opens the door to stacking wheat ZEP1 variants with other known Pst resistance genes in future breeding programs to enhance wheat tolerance to pathogens.
基金This study was funded by the National Natural Science Foundation of China(32170266)the Institutional Research Fund of Sichuan University(2020SCUNL106)the Fundamental Research Funds for the Central Universities(SCU2022D003).
文摘Carotenoids constitute a large group of natural pigments widely distributed in nature.These compounds not only provide fruits and flowers with distinctive colors,but also have significant health benefits for humans.Lutein and zeaxanthin,both oxygen-containing carotenoids,are considered to play vital roles in promoting ocular development and maintaining eye health.However,humans and mammals cannot synthesize these carotenoid derivatives,which can only be taken from certain fruits or vegetables.Here,by introducing four endogenous synthetic genes,SlLCYE,SlLCYB,SlHYDB,and SlHYDE under fruit-specific promoters,we report the metabolic engineering of lutein/zeaxanthin biosynthesis in tomato fruit.Transgenic lines overexpression of one(SlLCYE),two(SlLCYE and SlLCYB;SlLCYB and SlHYDB),and all these four synthetic genes re-established the lutein/zeaxanthin biosynthetic pathways in the ripe tomato fruit and thus resulted in various types of carotenoid riched lines.Metabolic analyses of these engineered tomato fruits showed the strategy involved expression of SlLCYE tends to produceα-carotene and lutein,as well as a higher content of β-carotene and zeaxanthin was detected in lines overexpressing SlLCYB.In addition,the different combinations of engineered tomatoes with riched carotenoids showed higher antioxidant capacity and were associated with a significantly extended shelf life during postharvest storage.This work provides a successful example of accurate metabolic engineering in tomato fruit,suggesting the potential utility for synthetic biology to improve agronomic traits in crops.These biofortified tomato fruits could be also exploited as new research subjects for studying the health benefits of carotenoid derivatives.
