Glucosinolates （GSs） are an important group of defensive phytochemicals mainly found in Brassicaceae. Plant hormones jasmonic acid （JA） and salicylic acid （SA） are major regulators of plant response to pathogen ...Glucosinolates （GSs） are an important group of defensive phytochemicals mainly found in Brassicaceae. Plant hormones jasmonic acid （JA） and salicylic acid （SA） are major regulators of plant response to pathogen attack. However, there is little information about the interactive effect of both elicitors on inducing GS biosynthesis in Chinese cabbage （Brassica rapa ssp. pekinensis）. In this study, we applied different concentrations of methyl jasmonate （MeJA） and/or SA onto the leaf and root of Chinese cabbage to investigate the time-course interactive profiles of GSs. Re- gardless of the site of the elicitation and the concentrations of the elicitors, the roots accumulated much more GSs and were more sensitive and more rapidly responsive to the elicitors than leaves. Irrespective of the elicitation site, MeJA had a greater inducing and longer lasting effect on GS accumulation than SA. All three components of indole GS （IGS） were detected along with aliphatic and aromatic GSs. However, IGS was a major component of total GSs that ac- cumulated rapidly in both root and leaf tissues in response to MeJA and SA elicitation. Neoglucobrassicin （neoGBC） did not respond to SA but to MeJA in leaf tissue, while it responded to both SA and MeJA in root tissue. Conversion of glucobrassicin （GBC） to neoGBC occurred at a steady rate over 3 d of elicitation. Increased accumulation of 4-methoxy glucobrassicin （4-MGBC） occurred only in the root irrespective of the type of elicitors and the site of elici- tation. Thus, accumulation of IGS is a major metabolic hallmark of SA＊ and MeJA-mediated systemic response sys- tems. SA exerted an antagonistic effect on the MeJA-induced root GSs irrespective of the site of elicitation. However, SA showed synergistic and antagonistic effects on the MeJA-induced leaf GSs when roots and leaves are elicitated for 3 d, respectively.展开更多
Glucosinolates(GSs) play an important role in plant defense systems and human nutrition.We investigated the content and composition of GSs in the shoots and roots of seven cultivars of pak choi.We found that 'Si Y...Glucosinolates(GSs) play an important role in plant defense systems and human nutrition.We investigated the content and composition of GSs in the shoots and roots of seven cultivars of pak choi.We found that 'Si Yue Man' had the highest total and aliphatic GS contents in the shoots and the highest benzenic GS content in the roots,'Shanghai Qing' contained the highest amounts of benzenic and total GS contents in the roots,while 'Nanjing Zhong Gan Bai' had the lowest benzenic,indole,and total GS contents in both the shoots and roots.Therefore,the 'Si Yue Man' cultivar appears to be a good candidate for future breeding.Variation between the shoots and roots was also examined,and a significant correlation among the total,aliphatic,and some individual GSs was found,which is of value in agricultural breeding.GS concentrations of the leaf,petiole,and root increased dramatically during the period of rapid growth of the dry matter of the plant 10 to 20 d after transplantation,reaching peak values on Day 20 and decreasing on Day 25.We conclude that the pak choi should be harvested and consumed from 20 to 25 d after transplantation to take advantages of the high GS content in the plant.展开更多
An 888-bp ful-length ascorbate peroxidase （APX） complementary DNA （cDNA） gene was cloned from Anthurium andraeanum, and designated as AnAPX. It contains a 110-bp 5′-noncoding region, a 28-bp 3′-noncoding region,...An 888-bp ful-length ascorbate peroxidase （APX） complementary DNA （cDNA） gene was cloned from Anthurium andraeanum, and designated as AnAPX. It contains a 110-bp 5′-noncoding region, a 28-bp 3′-noncoding region, and a 750-bp open reading frame （ORF）. This protein is hydrophilic with an aliphatic index of 81.64 and its structure consisting ofα-helixes,β-turns, and random coils. The AnAPX protein showed 93%, 87%, 87%, 87%, and 86% similarities to the APX homologs from Zantedeschia aethiopica, Vitis pseudoreticulata, Gossypium hirsutum, Elaeis guineensis, and Zea mays, respectively. AnAPX gene transcript was measured non-significantly in roots, stems, leaves, spathes, and spadices by real-time polymerase chain reaction （RT-PCR） analysis. Interestingly, this gene expression was remarkably up-regulated in response to a cold stress under 6 °C, implying that AnAPX might play an important role in A. andraeanum tolerance to cold stress. To confirm this function we overexpressed AnAPX in tobacco plants by transformation with an AnAPX expression construct driven by CaMV 35S promoter. The transformed tobacco seedlings under 4 °C showed less electrolyte leakage （EL） and malondialdehyde （MDA） content than the control. The content of MDA was correlated with chilling tolerance in these transgenic plants. These results show that AnAPX can prevent the chilling challenged plant from cellmembrane damage and ultimately enhance the plant cold tolerance.展开更多
基金supported by the National Natural Science Foundation of China(Nos.31000916 and 30871718)the Zhejiang Provincial Natural Science Foundation of China(Nos.LY14C150005,LZ14C150001,and Y3090538)+3 种基金the Scientific Research Starting Foundation for the Returned Overseas Chinese Scholars from the Ministry of Education of Chinathe Climbing Program for Young Academic Leaders in Universities of Zhejiang Province(No.pd2013230)the Qianjiang Talent Project of Zhejiang Province(No.qjd0902010)the Key Sci-Technology Project of Zhejiang Province(No.2010C12004),China
文摘Glucosinolates （GSs） are an important group of defensive phytochemicals mainly found in Brassicaceae. Plant hormones jasmonic acid （JA） and salicylic acid （SA） are major regulators of plant response to pathogen attack. However, there is little information about the interactive effect of both elicitors on inducing GS biosynthesis in Chinese cabbage （Brassica rapa ssp. pekinensis）. In this study, we applied different concentrations of methyl jasmonate （MeJA） and/or SA onto the leaf and root of Chinese cabbage to investigate the time-course interactive profiles of GSs. Re- gardless of the site of the elicitation and the concentrations of the elicitors, the roots accumulated much more GSs and were more sensitive and more rapidly responsive to the elicitors than leaves. Irrespective of the elicitation site, MeJA had a greater inducing and longer lasting effect on GS accumulation than SA. All three components of indole GS （IGS） were detected along with aliphatic and aromatic GSs. However, IGS was a major component of total GSs that ac- cumulated rapidly in both root and leaf tissues in response to MeJA and SA elicitation. Neoglucobrassicin （neoGBC） did not respond to SA but to MeJA in leaf tissue, while it responded to both SA and MeJA in root tissue. Conversion of glucobrassicin （GBC） to neoGBC occurred at a steady rate over 3 d of elicitation. Increased accumulation of 4-methoxy glucobrassicin （4-MGBC） occurred only in the root irrespective of the type of elicitors and the site of elici- tation. Thus, accumulation of IGS is a major metabolic hallmark of SA＊ and MeJA-mediated systemic response sys- tems. SA exerted an antagonistic effect on the MeJA-induced root GSs irrespective of the site of elicitation. However, SA showed synergistic and antagonistic effects on the MeJA-induced leaf GSs when roots and leaves are elicitated for 3 d, respectively.
基金Project supported by the National Natural Science Foundation of China (Nos.30871718 and 31201620)the Zhejiang Provincial Natural Science Foundation of China(No.R3080360)the Fund for Zhejiang Higher School Innovative Research Team(No.T200916),China
文摘Glucosinolates(GSs) play an important role in plant defense systems and human nutrition.We investigated the content and composition of GSs in the shoots and roots of seven cultivars of pak choi.We found that 'Si Yue Man' had the highest total and aliphatic GS contents in the shoots and the highest benzenic GS content in the roots,'Shanghai Qing' contained the highest amounts of benzenic and total GS contents in the roots,while 'Nanjing Zhong Gan Bai' had the lowest benzenic,indole,and total GS contents in both the shoots and roots.Therefore,the 'Si Yue Man' cultivar appears to be a good candidate for future breeding.Variation between the shoots and roots was also examined,and a significant correlation among the total,aliphatic,and some individual GSs was found,which is of value in agricultural breeding.GS concentrations of the leaf,petiole,and root increased dramatically during the period of rapid growth of the dry matter of the plant 10 to 20 d after transplantation,reaching peak values on Day 20 and decreasing on Day 25.We conclude that the pak choi should be harvested and consumed from 20 to 25 d after transplantation to take advantages of the high GS content in the plant.
基金supported by the Science and Technology Key Project ofZhejiang Province(No.2009C12095)the National NaturalScience Foundation of China(No.31200527)
文摘An 888-bp ful-length ascorbate peroxidase （APX） complementary DNA （cDNA） gene was cloned from Anthurium andraeanum, and designated as AnAPX. It contains a 110-bp 5′-noncoding region, a 28-bp 3′-noncoding region, and a 750-bp open reading frame （ORF）. This protein is hydrophilic with an aliphatic index of 81.64 and its structure consisting ofα-helixes,β-turns, and random coils. The AnAPX protein showed 93%, 87%, 87%, 87%, and 86% similarities to the APX homologs from Zantedeschia aethiopica, Vitis pseudoreticulata, Gossypium hirsutum, Elaeis guineensis, and Zea mays, respectively. AnAPX gene transcript was measured non-significantly in roots, stems, leaves, spathes, and spadices by real-time polymerase chain reaction （RT-PCR） analysis. Interestingly, this gene expression was remarkably up-regulated in response to a cold stress under 6 °C, implying that AnAPX might play an important role in A. andraeanum tolerance to cold stress. To confirm this function we overexpressed AnAPX in tobacco plants by transformation with an AnAPX expression construct driven by CaMV 35S promoter. The transformed tobacco seedlings under 4 °C showed less electrolyte leakage （EL） and malondialdehyde （MDA） content than the control. The content of MDA was correlated with chilling tolerance in these transgenic plants. These results show that AnAPX can prevent the chilling challenged plant from cellmembrane damage and ultimately enhance the plant cold tolerance.
