Background Mepiquat chloride(MC)is a widely used plant growth regulator in cotton(Gossypium hirsutum L.).It regulates endogenous hormone content and crosstalk to control plant height and promote lateral root(LR)develo...Background Mepiquat chloride(MC)is a widely used plant growth regulator in cotton(Gossypium hirsutum L.).It regulates endogenous hormone content and crosstalk to control plant height and promote lateral root(LR)development.However,the roles of cytokinins(CTKs)in the MC-induced increase in LR number in cotton seedlings remain unclear.Therefore,in this study,whole-genome transcriptome analysis was performed to elucidate the molecular mechanisms,CTK transformation,and CTK signaling pathway response to MC in cotton roots.Results In the present study,MC reduced the contents of the active CTK trans-zeatin(tZ)and N^(6)-isopentenyladenine(iP)but increased the levels of the nucleoside CTK trans-zeatin riboside(tZR)and N^(6)-isopentenyladenine riboside(iPR).RNA-seq data showed that the CTK biosynthesis genes GhIPTs and active CTK catabolism genes GhCKXs were obviously upregulated after MC treatment.The CTK-activating enzyme gene GhLOGs was repressed compared with the control.Furthermore,MC inhibited the expression of GhAHK4 and GhARR2/12,which are involved in the CTK signaling pathway,and activated the IAA-IAA14-ARF7/19 signaling module.Meanwhile,MC increased the expression levels of genes involved in sucrose synthesis,the cell cycle,cell division,and cell wall biosynthesis pathways.Silencing the GhCKX family separately decreased the LR number and active indole-3-acetic acid(IAA)level.The expression levels of GhPIN1,GhARF7,GhARF19,GhLBD16,GhLBD18,GhLBD29,and GhLBD33 were downregulated,but GhARR2/12 and GhIAA14 were upregulated.The total content of active CTKs was noticeably increased.The results of silencing the GhLOGs family were opposite to those of silencing GhCKXs.Silencing GhARR12 could upregulate GhPIN1 expression and increase LR number.In addition,the silenced GhCKXs,GhLOGs,and GhARR12 were less responsive to MCinduced LR growth than the control.Conclusion These results suggested that MC treatment could upregulate CTK-nucleoside biosynthesis and CTK metabolism genes to decrease active CTK levels,promoting crosstalk between CTKs and auxin signaling pathways to enhance LR initiation.展开更多
Protocol was developed for acceleration of microtuber induction in potato. It was observed that cytokinine (Kin), and both dark and light period had great influence on in vitro tuberization. Regarding concentration of...Protocol was developed for acceleration of microtuber induction in potato. It was observed that cytokinine (Kin), and both dark and light period had great influence on in vitro tuberization. Regarding concentration of Kin, 8 mg/l was found excellent for microtuber induction and formation under both dark and light conditions. Under continuous dark condition, higher percentage of explants (shoot) induced microtuber was observed than the short and long period of light conditions. For increasing the number and weight of microtuber product/explant, use of long photoperiod (16 h) is recommended.展开更多
Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally stud...Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally studied. It is found from the results of biological activity tests that some compounds have a remarkable activity on plant growth hormone. Compounds Ⅲa and Ⅲk have a good activity on cytokinin, compounds Ⅲe and Ⅲj and Ⅲl have an excellent activity on auxin.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31471434)。
文摘Background Mepiquat chloride(MC)is a widely used plant growth regulator in cotton(Gossypium hirsutum L.).It regulates endogenous hormone content and crosstalk to control plant height and promote lateral root(LR)development.However,the roles of cytokinins(CTKs)in the MC-induced increase in LR number in cotton seedlings remain unclear.Therefore,in this study,whole-genome transcriptome analysis was performed to elucidate the molecular mechanisms,CTK transformation,and CTK signaling pathway response to MC in cotton roots.Results In the present study,MC reduced the contents of the active CTK trans-zeatin(tZ)and N^(6)-isopentenyladenine(iP)but increased the levels of the nucleoside CTK trans-zeatin riboside(tZR)and N^(6)-isopentenyladenine riboside(iPR).RNA-seq data showed that the CTK biosynthesis genes GhIPTs and active CTK catabolism genes GhCKXs were obviously upregulated after MC treatment.The CTK-activating enzyme gene GhLOGs was repressed compared with the control.Furthermore,MC inhibited the expression of GhAHK4 and GhARR2/12,which are involved in the CTK signaling pathway,and activated the IAA-IAA14-ARF7/19 signaling module.Meanwhile,MC increased the expression levels of genes involved in sucrose synthesis,the cell cycle,cell division,and cell wall biosynthesis pathways.Silencing the GhCKX family separately decreased the LR number and active indole-3-acetic acid(IAA)level.The expression levels of GhPIN1,GhARF7,GhARF19,GhLBD16,GhLBD18,GhLBD29,and GhLBD33 were downregulated,but GhARR2/12 and GhIAA14 were upregulated.The total content of active CTKs was noticeably increased.The results of silencing the GhLOGs family were opposite to those of silencing GhCKXs.Silencing GhARR12 could upregulate GhPIN1 expression and increase LR number.In addition,the silenced GhCKXs,GhLOGs,and GhARR12 were less responsive to MCinduced LR growth than the control.Conclusion These results suggested that MC treatment could upregulate CTK-nucleoside biosynthesis and CTK metabolism genes to decrease active CTK levels,promoting crosstalk between CTKs and auxin signaling pathways to enhance LR initiation.
文摘Protocol was developed for acceleration of microtuber induction in potato. It was observed that cytokinine (Kin), and both dark and light period had great influence on in vitro tuberization. Regarding concentration of Kin, 8 mg/l was found excellent for microtuber induction and formation under both dark and light conditions. Under continuous dark condition, higher percentage of explants (shoot) induced microtuber was observed than the short and long period of light conditions. For increasing the number and weight of microtuber product/explant, use of long photoperiod (16 h) is recommended.
文摘Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally studied. It is found from the results of biological activity tests that some compounds have a remarkable activity on plant growth hormone. Compounds Ⅲa and Ⅲk have a good activity on cytokinin, compounds Ⅲe and Ⅲj and Ⅲl have an excellent activity on auxin.
