Cytokinins are a class of phytohormones that promote cell division and differentiation and are thought to affect plant immunity to multiple pathogens.However,a comprehensive analysis of cytokinin dehydrogenase/oxidase...Cytokinins are a class of phytohormones that promote cell division and differentiation and are thought to affect plant immunity to multiple pathogens.However,a comprehensive analysis of cytokinin dehydrogenase/oxidase(CKX)family genes in cabbage has not been reported.In this study,a total of 36 CKX genes were identified using a genome-wide search method.Phylogenetic analysis classified these genes into three groups.They were distributed unevenly across nine chromosomes in B.oleracea,and 15 of them did not contain any introns.The results of colinearity analysis showed that 36 CKX gene in Arabidopsis was present in several copies in the Brassica oleracea genome.An analysis of cisacting elements indicated that all genes possessed at least one stress or hormone responsive cis-acting element.A heatmap of CKX gene expression showed the patterns of expression of these genes in various tissues and organs.Three genes(Bol028363,Bol031036 and Bol018140)were relatively highly expressed in all of the investigated tissues under normal conditions,showing the expression profile of housekeeping genes.Generally,the expression patterns of CKX genes in Jingfeng 1 and Xiangan 336 were quite different under the same treatment.Notably,three genes(Bol020547,Bol028392 and Bol045724)were significantly down-regulated and up-regulated in the susceptible and resistant material,respectively,after inoculation,which may indicate their crucial roles in resistance to clubroot disease.The results provide insights for better understanding the roles of CKX genes in the B.oleracea–P.brassicae interaction.展开更多
The synergistic effects of cellobiose dehydro-genase (CDH) and manganese-dependent peroxidases (MnP) on the degradation of kraft pulp cellulolytic enzyme lignin (CEL) were investigated. Addition of CDH significantly i...The synergistic effects of cellobiose dehydro-genase (CDH) and manganese-dependent peroxidases (MnP) on the degradation of kraft pulp cellulolytic enzyme lignin (CEL) were investigated. Addition of CDH significantly increased the amount of water-soluble products reduced from CEL by MnP. CDH facilitated the reduction of the contents of methoxyl, carboxyl, phenolic hydroxyl and total hydroxyl groups of CEL by MnP. 1H-NMR analysis showed that addition of CDH also decreased further the amount of protons of CEL degraded by MnP. The results proved for the first time that CDH could promote degradation of lignin by MnP and suggest that CDH could not only promote degradation of cellulose but also is an important part of the lignin biodeg-radation system.展开更多
This review chronicles the development of the cytokinin research during the last 30 years. Cytokinin and auxin are the two major plant growth hormones that control virtually all aspects of growth and development in hi...This review chronicles the development of the cytokinin research during the last 30 years. Cytokinin and auxin are the two major plant growth hormones that control virtually all aspects of growth and development in higher plants. The pathways for cytokinin biosynthesis and metabolism have been characterized by the identification of isopentenyl pyrophosphate transferase, cytokinin oxidases, cytokinin hydroxylase, zeatin cis-/trans-isomerase, cytokinin phosphoribosyl hydrolases, cytokinin-specific riboside phosphorylase, and others enzymes. Loss-of function mutant phenotypes of cytokinin degradation/activating enzymes indicate the regulation of concentration and spatial distribution of bio-active cytokinin plays a pivotal role in the increase in panicle size, in the numbers of floral organs, and eventually in seed yield. One of the most fundamental questions in the cytokinin field is one concerning the prevalence of cis-zeatin in monocotyledonous crops (rice and maize) and in dicotyledonous legumes (pea, chickpea) and potato/sweet potato. A hypothesis is that cis-zeatin is synthesized by the cis-specific hydroxylation of the terminal methyl group of N6-isopentenyl side chain of N6-isopentenyl adenosine (i6Ado) or of their mono-, di-, or tri-phosphates catalyzed by the cis-specific hydroxylase. A second potential pathway is the isomerization of trans-zeatin to cis-zeatin by zeatin cis-/trans-isomerase. A second fundamental question to be addressed is the physiological role of cis-zeatin. Some have argued for a special function of cis-zeatin to account for the prevalence of the cis-zeatin in the plant kingdom from algae to higher plants.展开更多
[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked ...[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked into benziothiazolinone (1 000 ppm), lysozyme (500 ppm), lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water for 5 min, respectively. Non-treated sweet cherry was set as control. All the sweet cherries were then put into 3 mm thick PE bags and preserved at (-0.5±0.5) ℃. [Result] The results showed that the malate dehydrogenase (MDH) activity of benziothiazolinone treatment researched a significant peak on the 14 th d, while the MDH activity of Lysozyme (500 ppm), Lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water treatments began to increase on the 20 th d; the polyphenol oxidase (PPO) activity in various treatments showed a decreasing trend during the experiment, which researched a significant peak on the 14 th d, while that in water treatment was decreased consistently; on the 21 st d, the PPO activity in each treatment increased slowly; the titratable acid (TA) content in preservative treatments was higher than that in both water treatment and control; the soluble solid (SSC) content showed no significant difference between various treatments and between experimental treatment and control; on the 40 th d, the healthy fruit rate in preservative treatments was significantly higher than that in water treatment and control. [Conclusion] Benziothiazolinone, lysozyme and other preservatives show good effects on preservation of sweet cherry; lysozyme treatment can decrease the activity of malate dehydrogenase, maintain the relatively high content of organic acid and significantly improve the healthy fruit rate within a certain period of time.展开更多
基金supported by the Youth Science Fund Project(Grant No. 31801876)。
文摘Cytokinins are a class of phytohormones that promote cell division and differentiation and are thought to affect plant immunity to multiple pathogens.However,a comprehensive analysis of cytokinin dehydrogenase/oxidase(CKX)family genes in cabbage has not been reported.In this study,a total of 36 CKX genes were identified using a genome-wide search method.Phylogenetic analysis classified these genes into three groups.They were distributed unevenly across nine chromosomes in B.oleracea,and 15 of them did not contain any introns.The results of colinearity analysis showed that 36 CKX gene in Arabidopsis was present in several copies in the Brassica oleracea genome.An analysis of cisacting elements indicated that all genes possessed at least one stress or hormone responsive cis-acting element.A heatmap of CKX gene expression showed the patterns of expression of these genes in various tissues and organs.Three genes(Bol028363,Bol031036 and Bol018140)were relatively highly expressed in all of the investigated tissues under normal conditions,showing the expression profile of housekeeping genes.Generally,the expression patterns of CKX genes in Jingfeng 1 and Xiangan 336 were quite different under the same treatment.Notably,three genes(Bol020547,Bol028392 and Bol045724)were significantly down-regulated and up-regulated in the susceptible and resistant material,respectively,after inoculation,which may indicate their crucial roles in resistance to clubroot disease.The results provide insights for better understanding the roles of CKX genes in the B.oleracea–P.brassicae interaction.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 20077015 and 29906005) by the Special Foundation of the Ministry of Education of China (Grant No. 200023).
文摘The synergistic effects of cellobiose dehydro-genase (CDH) and manganese-dependent peroxidases (MnP) on the degradation of kraft pulp cellulolytic enzyme lignin (CEL) were investigated. Addition of CDH significantly increased the amount of water-soluble products reduced from CEL by MnP. CDH facilitated the reduction of the contents of methoxyl, carboxyl, phenolic hydroxyl and total hydroxyl groups of CEL by MnP. 1H-NMR analysis showed that addition of CDH also decreased further the amount of protons of CEL degraded by MnP. The results proved for the first time that CDH could promote degradation of lignin by MnP and suggest that CDH could not only promote degradation of cellulose but also is an important part of the lignin biodeg-radation system.
文摘This review chronicles the development of the cytokinin research during the last 30 years. Cytokinin and auxin are the two major plant growth hormones that control virtually all aspects of growth and development in higher plants. The pathways for cytokinin biosynthesis and metabolism have been characterized by the identification of isopentenyl pyrophosphate transferase, cytokinin oxidases, cytokinin hydroxylase, zeatin cis-/trans-isomerase, cytokinin phosphoribosyl hydrolases, cytokinin-specific riboside phosphorylase, and others enzymes. Loss-of function mutant phenotypes of cytokinin degradation/activating enzymes indicate the regulation of concentration and spatial distribution of bio-active cytokinin plays a pivotal role in the increase in panicle size, in the numbers of floral organs, and eventually in seed yield. One of the most fundamental questions in the cytokinin field is one concerning the prevalence of cis-zeatin in monocotyledonous crops (rice and maize) and in dicotyledonous legumes (pea, chickpea) and potato/sweet potato. A hypothesis is that cis-zeatin is synthesized by the cis-specific hydroxylation of the terminal methyl group of N6-isopentenyl side chain of N6-isopentenyl adenosine (i6Ado) or of their mono-, di-, or tri-phosphates catalyzed by the cis-specific hydroxylase. A second potential pathway is the isomerization of trans-zeatin to cis-zeatin by zeatin cis-/trans-isomerase. A second fundamental question to be addressed is the physiological role of cis-zeatin. Some have argued for a special function of cis-zeatin to account for the prevalence of the cis-zeatin in the plant kingdom from algae to higher plants.
基金Supported by Fund from Technology Bureau of Wuhan City (201120722215-2)~~
文摘[Objective] This study aimed to investigate the effects of different preservative treatments on physiological metabolism and preservation of sweet cherry. [Method] Sweet cherry (Prunus avium var. Summit) was soaked into benziothiazolinone (1 000 ppm), lysozyme (500 ppm), lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water for 5 min, respectively. Non-treated sweet cherry was set as control. All the sweet cherries were then put into 3 mm thick PE bags and preserved at (-0.5±0.5) ℃. [Result] The results showed that the malate dehydrogenase (MDH) activity of benziothiazolinone treatment researched a significant peak on the 14 th d, while the MDH activity of Lysozyme (500 ppm), Lysozyme (500 ppm) + NPS polysaccharide (5 000 ppm) and water treatments began to increase on the 20 th d; the polyphenol oxidase (PPO) activity in various treatments showed a decreasing trend during the experiment, which researched a significant peak on the 14 th d, while that in water treatment was decreased consistently; on the 21 st d, the PPO activity in each treatment increased slowly; the titratable acid (TA) content in preservative treatments was higher than that in both water treatment and control; the soluble solid (SSC) content showed no significant difference between various treatments and between experimental treatment and control; on the 40 th d, the healthy fruit rate in preservative treatments was significantly higher than that in water treatment and control. [Conclusion] Benziothiazolinone, lysozyme and other preservatives show good effects on preservation of sweet cherry; lysozyme treatment can decrease the activity of malate dehydrogenase, maintain the relatively high content of organic acid and significantly improve the healthy fruit rate within a certain period of time.