Dear Editor,In most flowering plants, the stigma of the flower represents the barrier that prevents any unrelated or incompatible （genetically similar） pollen from germination and fertilizing the ovule, leading to e...Dear Editor,In most flowering plants, the stigma of the flower represents the barrier that prevents any unrelated or incompatible （genetically similar） pollen from germination and fertilizing the ovule, leading to either defective or genetically unfavorable embryos. In Brassicaceae, self-incompatibility （SI） is a genetic mechanism in the stigmas that can discern compatible versus incompatible mate （pollen）, in turn, rejecting self or incompatible pollen, while allowing non-self or compatible pollen to develop successfully to fertilize the ovules. Thus, stigmas have evolved complex mechanisms and specialized proteins to reject incompatible mates and to recognize and accept compatible pollen （Doucet et al., 2016）. The fact that SI has been shown to exclusively operate in the stigmas temporally before and during anthesis （Kandasamy et al., 1993） indicates that multiple metabolic pathways essential for pollination exist in these stigmatic papillary cells.展开更多
Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L...Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L-1. The con centration of carbencillin (carb) was 500 mg L-1. 14 transgenic cauliflower pla nts were obtained. The putative transformants were assayed by PCR and Southern b lotting analysis. The results indicated that CpTI gene was transferred into caul iflower successfully.展开更多
The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed...The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed production of several cabbage cultivars in China. During the development of dominant male sterility lines in cabbage, the conventional identification of homozygous male-sterile plants （CDMs399-3/CDMs399-3） is a laborious and time-consuming process. For marker-assisted selection （MAS） of the gene CDMs399-3 transferred into key spring cabbage line 397, expressed sequence tag-simple sequence repeats （EST-SSR） and SSR technology were used to identify markers that were linked to CDMs399-3 based on method of bulked segregant analysis （BSA）. By screening a set of 978 EST-SSRs and 395 SSRs, a marker BoE332 linked to the CDMs399-3 at a distance of 3.6 cM in the genetic background of cabbage line 397 were identified. 7 homozygons male-sterile plants in population P1170 with 20 plants were obtained finally via MAS of BoE332. Thus, BoE332 will greatly facilitate the transferring of the gene CDMs399-3 into the key spring cabbage line 397 and improve the application of DGMS in cabbage hybrid breeding.展开更多
Eight F<sub>1</sub>-hybrid cultivars of broccoli were studied.We obtained cell division,celled colonies and p-calli in 5 cultivars,roots and shoots regeneration in one cultivar.The leavesof propagated plan...Eight F<sub>1</sub>-hybrid cultivars of broccoli were studied.We obtained cell division,celled colonies and p-calli in 5 cultivars,roots and shoots regeneration in one cultivar.The leavesof propagated plantlets in vitro were cut into 1—2mm pieces,isolated with an enzyme solutioncontaining 2% cellulase and 1%macerase on a rotary shaker（50 rpm,21℃,3h,2500 lux light）,and purified with a 0.5M sucrose solution.The purified protoplasts were placed on a drop of 1%agarose.2—3 ml liquid medium was added around the agarose drops,and all of the cultures wereincubated at 25℃ under light（4000 lux）for 16 hours.3—5 days after isolation the cell divisionwas found.About 7 days after incubation 4 multicellular colonies were formed.After 3—5 wksome p-calli were developed.When the p-calli were 2—3 mm in diameter it was transferred to asolidified medium.Once they were developed to 1 cm in diameter they were transferred on a re-generation medium.About 5 months after incubation some roots and shoots grown from the calliwere展开更多
Broccoli(Brassica oleracea var.italica),also called green broccoli,green cauliflower,and calabrese,belongs to genus Brassica in family Cruciferae,and is annual or biennial herbaceous plant.Both broccoli and cauliflowe...Broccoli(Brassica oleracea var.italica),also called green broccoli,green cauliflower,and calabrese,belongs to genus Brassica in family Cruciferae,and is annual or biennial herbaceous plant.Both broccoli and cauliflower are varieties of Brassica oleracea L.Broccoli is rich in nutrients.Its protein,amino acids and vitamins are higher than cauliflower,and broccoli is easy to grow,the supply period is long,and it has a good market and economic value.This paper introduced broccoli-related information from broccoli's nutritional value,cultivation techniques,existing problems and prospects.In addition,on the basis of existing studies,it discussed the future development prospects of broccoli,in order to promote the production research of broccoli in China.展开更多
Cytoplasmic male sterility (CMS) is a maternally inherited trait that prevents the production of function pollen, but maintains female fertility. It has been widely used in breeding programs to product F_1 hybrid seed
Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the mo...Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the molecular mechanisms through which MY regulates sulforaphane biosynthesis in plants remains largely unknown. Here, we discovered that the change of sulforaphane content in broccoli sprouts caused by exogenous selenite treatments is positively related to BoMY expression. BoMY overexpression in the Arabidopsis thaliana tgg1 mutants could dramatically increase myrosinase activity and sulforaphane content in the rosette leaves of 35S::BoMY/tgg1 and rescue its phenotypes.Moreover, an obvious increase of myrosinase activity and sulforaphane content was displayed in transgenic BoMY-overexpressed broccoli lines.In addition, a 2 033 bp promoter fragment of BoMY was isolated. Yeast one-hybrid(Y1H) library screening experiment uncovered that one bHLH transcription factor, BoFAMA, could directly bind to BoMY promoter to activate its expression, which was further evidenced by Y1H assay and dual-luciferase reporter assay. BoFAMA is a selenite-responsive transcription factor that is highly expressed in broccoli leaves;its protein is solely localized to nucleus. Additionally, genetic evidence suggested that the knockdown of FAMA gene in Arabidopsis thaliana could significantly decrease sulforaphane yield by inhibiting the expression of myrosinase genes. Interestingly, exogenous selenite supply could partially restore the low level of sulforaphane content in transgenic Arabidopsis FAMA-silencing plants. Our findings uncover a novel function of FAMAMY module in the regulation of selenite-mediated sulforaphane synthesis and provide a new insights into the molecular mechanism by which selenite regulates the accumulation of sulforaphane in plants.展开更多
Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Bra...Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Brassica oleracea L.ssp.var.botrytis)is rich in phytochemicals and is an important crop grown all over the world.This study investigates carotenoid and chlorophyll concentrations in differently pigmented cultivars and elucidates the role of transcriptional regulation of carotenoid accumulation including lutein andβ-carotene.Here,we characterised changes in pigments by UHPLC-DAD-ToF-MS and changes in transcript levels of carotenoid metabolic genes by qRT-PCR in florets and leaves of orange(‘Jaffa'and‘Sunset'),purple(‘Di Sicilia Violetto'and‘Graffiti'),green(‘Trevi')and white(‘Clapton')cultivars.Transcript levels of all carotenoid metabolic genes showed different transcript level patterns in the leaves and florets.Compared to the other cultivars,the orange cultivars had the highest levels ofβ-carotene in the florets and lutein in the leaves resulting in changes lutein/β-carotene ratios.In the green cultivar,higher transcript levels were also found,especially for phytoene synthase and phytoene desaturase genes of the core biosynthesis pathway.However,no increased carotenoid concentrations were observed,possibly due to a higher carotenoid turnover induced by the carotenoid cleavage dioxygenase 4 in the green cultivar.In the white(‘Clapton')and purple(‘Di Sicilia Violetto'and‘Graffiti')cultivars the phytoene desaturase transcript levels as well as carotenoid concentrations were low.Chlorophyll concentrations changed in trend comparable to the carotenoid concentrations and were only significantly lower in the leaves of the orange cultivar‘Jaffa'.Also,the chlorophyll a/b ratio changed in‘Jaffa'.In florets the highest chlorophylls concentrations were observed for the green cultivar(‘Trevi')and the purple cultivar(‘Di Sicilia Violetto').Taken together,the study demonstrates the complex source-sink relationship of carotenoid accumulation in different coloured cauliflower.展开更多
The vegetative development of cabbage(Brassica oleracea var.capitata)passes through seedling,rosette,folding and heading stages.Leaves that form the rosette are large and mostly flat.In the following developmental sta...The vegetative development of cabbage(Brassica oleracea var.capitata)passes through seedling,rosette,folding and heading stages.Leaves that form the rosette are large and mostly flat.In the following developmental stages,the plants produce leaves that curve inward to produce the leafy head.Many microRNAs and their target genes have been described participating in leaf development and leaf curvature.The aim of this study is to investigate the role of miRNA-regulated genes in the transition from the rosette to the heading stage.We compared the mi RNA and gene abundances between emerging rosette and heading leaves.To remove transcripts(miRNAs and genes)whose regulation was most likely associated with plant age rather than the change from rosette to heading stage,we utilized a non-heading collard green(B.oleracea var.acephala)morphotype as control.This resulted in 33 DEMs and 1998 DEGs with likely roles in the transition from rosette to heading stage in cabbage.Among these 1998 DEGs,we found enriched GO terms related to DNA-binding transcription factor activity,transcription regulator activity,iron ion binding,and photosynthesis.We predicted the target genes of these 33 DEMs and focused on the subset that was differentially expressed(1998DEGs)between rosette and heading stage leaves to construct mi RNA-target gene interaction networks.Our main finding is a role for miR396b-5p targeting two Arabidopsis thaliana orthologues of GROWTH REGULATING FACTORs 3(GRF3)and 4(GRF4)in pointed cabbage head formation.展开更多
Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growt...Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.展开更多
ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(...ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(RT-PCR)and deposited in Gen Bank(accession number KY662297).The Boa ZDS gene contains an open reading frame of 1 686 bp that encodes a 561-amino acid protein.Sequence analysis indicates that the ZDS protein is apparently conserved during plant evolution and is most closely related to B.oleracea var.capitata and B.rapa.The promoter sequence of the Boa ZDS gene was predicted to harbor several cis-acting elements that are related to light and phytohormone responses.Semiquantitative RT-PCR analysis showed that Boa ZDS expression varied among different developmental stages and organs.Relative ZDS expression remained stable during germination and seedling stages and rapidly increased at the mature leaf stage.The leaves showed the highest ZDS expression levels compared to the other organs.ZDS expression decreased in all flower tissues during blooming.The fused protein of Boa ZDS was obtained by prokaryotic expression.Heterologous expression of Boa ZDS in Escherichia coli confirmed that Boa ZDS encodes a functionalζ-carotene desaturase that increases β-carotene accumulation in E.coli cells harboring a β-carotene-producing plasmid.The findings of the present study provide a molecular basis for the elucidation of ZDS gene function in Chinese kale.展开更多
文摘Dear Editor,In most flowering plants, the stigma of the flower represents the barrier that prevents any unrelated or incompatible （genetically similar） pollen from germination and fertilizing the ovule, leading to either defective or genetically unfavorable embryos. In Brassicaceae, self-incompatibility （SI） is a genetic mechanism in the stigmas that can discern compatible versus incompatible mate （pollen）, in turn, rejecting self or incompatible pollen, while allowing non-self or compatible pollen to develop successfully to fertilize the ovules. Thus, stigmas have evolved complex mechanisms and specialized proteins to reject incompatible mates and to recognize and accept compatible pollen （Doucet et al., 2016）. The fact that SI has been shown to exclusively operate in the stigmas temporally before and during anthesis （Kandasamy et al., 1993） indicates that multiple metabolic pathways essential for pollination exist in these stigmatic papillary cells.
文摘Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L-1. The con centration of carbencillin (carb) was 500 mg L-1. 14 transgenic cauliflower pla nts were obtained. The putative transformants were assayed by PCR and Southern b lotting analysis. The results indicated that CpTI gene was transferred into caul iflower successfully.
基金supported by the National Science and Technology Ministry of China (2008BADB1B02 and 2009BADB8B03)the Core Research Budget of the Non-profit Governmental Research Institution (ICS, CAAS) (1610032011011)+1 种基金the China Agriculture Research System (CARS-25)the National High Technology Research and Development Program of China (863 Program, 2012AA100101)
文摘The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed production of several cabbage cultivars in China. During the development of dominant male sterility lines in cabbage, the conventional identification of homozygous male-sterile plants （CDMs399-3/CDMs399-3） is a laborious and time-consuming process. For marker-assisted selection （MAS） of the gene CDMs399-3 transferred into key spring cabbage line 397, expressed sequence tag-simple sequence repeats （EST-SSR） and SSR technology were used to identify markers that were linked to CDMs399-3 based on method of bulked segregant analysis （BSA）. By screening a set of 978 EST-SSRs and 395 SSRs, a marker BoE332 linked to the CDMs399-3 at a distance of 3.6 cM in the genetic background of cabbage line 397 were identified. 7 homozygons male-sterile plants in population P1170 with 20 plants were obtained finally via MAS of BoE332. Thus, BoE332 will greatly facilitate the transferring of the gene CDMs399-3 into the key spring cabbage line 397 and improve the application of DGMS in cabbage hybrid breeding.
文摘Eight F<sub>1</sub>-hybrid cultivars of broccoli were studied.We obtained cell division,celled colonies and p-calli in 5 cultivars,roots and shoots regeneration in one cultivar.The leavesof propagated plantlets in vitro were cut into 1—2mm pieces,isolated with an enzyme solutioncontaining 2% cellulase and 1%macerase on a rotary shaker（50 rpm,21℃,3h,2500 lux light）,and purified with a 0.5M sucrose solution.The purified protoplasts were placed on a drop of 1%agarose.2—3 ml liquid medium was added around the agarose drops,and all of the cultures wereincubated at 25℃ under light（4000 lux）for 16 hours.3—5 days after isolation the cell divisionwas found.About 7 days after incubation 4 multicellular colonies were formed.After 3—5 wksome p-calli were developed.When the p-calli were 2—3 mm in diameter it was transferred to asolidified medium.Once they were developed to 1 cm in diameter they were transferred on a re-generation medium.About 5 months after incubation some roots and shoots grown from the calliwere
文摘Broccoli(Brassica oleracea var.italica),also called green broccoli,green cauliflower,and calabrese,belongs to genus Brassica in family Cruciferae,and is annual or biennial herbaceous plant.Both broccoli and cauliflower are varieties of Brassica oleracea L.Broccoli is rich in nutrients.Its protein,amino acids and vitamins are higher than cauliflower,and broccoli is easy to grow,the supply period is long,and it has a good market and economic value.This paper introduced broccoli-related information from broccoli's nutritional value,cultivation techniques,existing problems and prospects.In addition,on the basis of existing studies,it discussed the future development prospects of broccoli,in order to promote the production research of broccoli in China.
文摘Cytoplasmic male sterility (CMS) is a maternally inherited trait that prevents the production of function pollen, but maintains female fertility. It has been widely used in breeding programs to product F_1 hybrid seed
基金funded by the National Key Research and Development Program of China (Grant Nos.2022YFF1003000,2022YFE0108300)the Natural Science Foundation of China (Grant Nos.32272747,32072585,32072568)+1 种基金the Natural Science Foundation of Hunan Province (Grant Nos.2021JJ30324,2021JJ30345)the Outstanding Youth Project of Educational Department of Hunan Province (Grant No.20B275)。
文摘Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the molecular mechanisms through which MY regulates sulforaphane biosynthesis in plants remains largely unknown. Here, we discovered that the change of sulforaphane content in broccoli sprouts caused by exogenous selenite treatments is positively related to BoMY expression. BoMY overexpression in the Arabidopsis thaliana tgg1 mutants could dramatically increase myrosinase activity and sulforaphane content in the rosette leaves of 35S::BoMY/tgg1 and rescue its phenotypes.Moreover, an obvious increase of myrosinase activity and sulforaphane content was displayed in transgenic BoMY-overexpressed broccoli lines.In addition, a 2 033 bp promoter fragment of BoMY was isolated. Yeast one-hybrid(Y1H) library screening experiment uncovered that one bHLH transcription factor, BoFAMA, could directly bind to BoMY promoter to activate its expression, which was further evidenced by Y1H assay and dual-luciferase reporter assay. BoFAMA is a selenite-responsive transcription factor that is highly expressed in broccoli leaves;its protein is solely localized to nucleus. Additionally, genetic evidence suggested that the knockdown of FAMA gene in Arabidopsis thaliana could significantly decrease sulforaphane yield by inhibiting the expression of myrosinase genes. Interestingly, exogenous selenite supply could partially restore the low level of sulforaphane content in transgenic Arabidopsis FAMA-silencing plants. Our findings uncover a novel function of FAMAMY module in the regulation of selenite-mediated sulforaphane synthesis and provide a new insights into the molecular mechanism by which selenite regulates the accumulation of sulforaphane in plants.
基金supported by the Federal Office for Agriculture and Food(BLE)of Germany[Grant No.2816DOKI07(Carcauli)]。
文摘Carotenoids and chlorophylls are among the most widely distributed pigments in nature that play essential roles in the photosynthetic apparatus and confer diverse colours in plants.Among all vegetables,cauliflower(Brassica oleracea L.ssp.var.botrytis)is rich in phytochemicals and is an important crop grown all over the world.This study investigates carotenoid and chlorophyll concentrations in differently pigmented cultivars and elucidates the role of transcriptional regulation of carotenoid accumulation including lutein andβ-carotene.Here,we characterised changes in pigments by UHPLC-DAD-ToF-MS and changes in transcript levels of carotenoid metabolic genes by qRT-PCR in florets and leaves of orange(‘Jaffa'and‘Sunset'),purple(‘Di Sicilia Violetto'and‘Graffiti'),green(‘Trevi')and white(‘Clapton')cultivars.Transcript levels of all carotenoid metabolic genes showed different transcript level patterns in the leaves and florets.Compared to the other cultivars,the orange cultivars had the highest levels ofβ-carotene in the florets and lutein in the leaves resulting in changes lutein/β-carotene ratios.In the green cultivar,higher transcript levels were also found,especially for phytoene synthase and phytoene desaturase genes of the core biosynthesis pathway.However,no increased carotenoid concentrations were observed,possibly due to a higher carotenoid turnover induced by the carotenoid cleavage dioxygenase 4 in the green cultivar.In the white(‘Clapton')and purple(‘Di Sicilia Violetto'and‘Graffiti')cultivars the phytoene desaturase transcript levels as well as carotenoid concentrations were low.Chlorophyll concentrations changed in trend comparable to the carotenoid concentrations and were only significantly lower in the leaves of the orange cultivar‘Jaffa'.Also,the chlorophyll a/b ratio changed in‘Jaffa'.In florets the highest chlorophylls concentrations were observed for the green cultivar(‘Trevi')and the purple cultivar(‘Di Sicilia Violetto').Taken together,the study demonstrates the complex source-sink relationship of carotenoid accumulation in different coloured cauliflower.
基金funded by the Mexican government through the Consejo Nacional de Ciencia y Tecnología (CONACYT),C.V.761325,for the PhD project of Jorge Aleman-Baez。
文摘The vegetative development of cabbage(Brassica oleracea var.capitata)passes through seedling,rosette,folding and heading stages.Leaves that form the rosette are large and mostly flat.In the following developmental stages,the plants produce leaves that curve inward to produce the leafy head.Many microRNAs and their target genes have been described participating in leaf development and leaf curvature.The aim of this study is to investigate the role of miRNA-regulated genes in the transition from the rosette to the heading stage.We compared the mi RNA and gene abundances between emerging rosette and heading leaves.To remove transcripts(miRNAs and genes)whose regulation was most likely associated with plant age rather than the change from rosette to heading stage,we utilized a non-heading collard green(B.oleracea var.acephala)morphotype as control.This resulted in 33 DEMs and 1998 DEGs with likely roles in the transition from rosette to heading stage in cabbage.Among these 1998 DEGs,we found enriched GO terms related to DNA-binding transcription factor activity,transcription regulator activity,iron ion binding,and photosynthesis.We predicted the target genes of these 33 DEMs and focused on the subset that was differentially expressed(1998DEGs)between rosette and heading stage leaves to construct mi RNA-target gene interaction networks.Our main finding is a role for miR396b-5p targeting two Arabidopsis thaliana orthologues of GROWTH REGULATING FACTORs 3(GRF3)and 4(GRF4)in pointed cabbage head formation.
基金Supported by Science and Technology Development Planning Project of Henan Province(182102110305)
文摘Collard variety( Brassis oleracea L. var. acephala f. tricolor Hort.) as a research material was treated with exogenous H_2O_2 and H_2O_2 scavenger dimethyl thiourea under 100 mmol/L NaC l stress. Two days later,growth rate,dry weight,fresh weight and relative water content of the plants were determined. After 6h of treatment,the activity and gene expression of three antioxidant enzymes,superoxide dismutase( SOD),catalase( CAT) and ascorbate peroxidase( APX) in plants,were measured. The results showed that the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in collard seedlings were higher in the treatment of salt stress with the addition of 0. 05 mmol/L exogenous H_2O_2 than in the simple salt stress treatment; and when endogenous H_2O_2 was removed,the growth rate,dry weight,fresh weight,relative water content,and the activity and gene expression of the three antioxidant enzymes in plant seedlings were lower than those under simple salt stress. It is speculated that under salt stress,H_2O_2 is involved in the regulation of antioxidant defense gene expression,and it might be an important regulator of salt-induced antioxidant system in collard leaves.
基金supported by National Natural Science Foundation of China(31500247)Key Project of Department of Education of Sichuan Province(14ZA0016)Natural Science Foundation of Zhejiang Province(LZ15C150001)
文摘ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(RT-PCR)and deposited in Gen Bank(accession number KY662297).The Boa ZDS gene contains an open reading frame of 1 686 bp that encodes a 561-amino acid protein.Sequence analysis indicates that the ZDS protein is apparently conserved during plant evolution and is most closely related to B.oleracea var.capitata and B.rapa.The promoter sequence of the Boa ZDS gene was predicted to harbor several cis-acting elements that are related to light and phytohormone responses.Semiquantitative RT-PCR analysis showed that Boa ZDS expression varied among different developmental stages and organs.Relative ZDS expression remained stable during germination and seedling stages and rapidly increased at the mature leaf stage.The leaves showed the highest ZDS expression levels compared to the other organs.ZDS expression decreased in all flower tissues during blooming.The fused protein of Boa ZDS was obtained by prokaryotic expression.Heterologous expression of Boa ZDS in Escherichia coli confirmed that Boa ZDS encodes a functionalζ-carotene desaturase that increases β-carotene accumulation in E.coli cells harboring a β-carotene-producing plasmid.The findings of the present study provide a molecular basis for the elucidation of ZDS gene function in Chinese kale.
