[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistr...[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a ＂U＂-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a ＂U＂ shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root.展开更多
Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but als...Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but also controlled by a variety of structural genes.Nonetheless,the molecular mechanism underlying ginsenoside biosynthesis has always been a topic in the discussion of ginseng secondary metabolites.Squalene epoxidase(SQE)is a key enzyme in the mevalonic acid pathway,which affects the biosynthesis of secondary metabolites such as terpenoid.Using ginseng transcriptome,expression,and ginsenoside content databases,this study employed bioinformatic methods to systematically analyze the genes encoding SQE in ginseng.We first selected six PgSQE candidates that were closely involved in ginsenoside biosynthesis and then identified PgSQE08-01 to be highly associated with ginsenoside biosynthesis.Next,we constructed the overexpression vector pCAMBIA3301-PgSQE08-01 and the RNAi vector pART27-PgSQE08-01 and transformed ginseng adventitious roots using Agrobacterium rhizogenes,to obtain positive hairy-root clones.Thereafter,quantitative reverse transcriptionpolymerase chain reaction and high-performance liquid chromatography were used to determine the expression of relevant genes and ginsenoside content,respectively.Then,we focused on the function of PgSQE08-01 gene,which was noted to be involved in ginsenoside biosynthesis.Thus,these findings not only provided a molecular basis for the identification of important functional genes in ginseng but also enriched genetic resources for the biosynthesis of ginsenosides using synthetic biology.展开更多
Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in t...Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D（-）-2-amino-5-phosphonopentanoic acid（AP-5）,or both once daily for 15 days.Compared with injured drug na？ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity（as assessed by immunohistochemistry） and protein（as determined by western blot assay） in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.展开更多
基金Supported by Natural Science Foundation of Ningxia Hui Autonomous Region(NZ0932)National Key Technology R & D Program of China(20068AI06A15-11)~~
文摘[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a ＂U＂-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a ＂U＂ shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root.
基金This work was supported by an award from the Department of Science and Technology of Jilin Province(20210402043GH and 20210204063YY).
文摘Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but also controlled by a variety of structural genes.Nonetheless,the molecular mechanism underlying ginsenoside biosynthesis has always been a topic in the discussion of ginseng secondary metabolites.Squalene epoxidase(SQE)is a key enzyme in the mevalonic acid pathway,which affects the biosynthesis of secondary metabolites such as terpenoid.Using ginseng transcriptome,expression,and ginsenoside content databases,this study employed bioinformatic methods to systematically analyze the genes encoding SQE in ginseng.We first selected six PgSQE candidates that were closely involved in ginsenoside biosynthesis and then identified PgSQE08-01 to be highly associated with ginsenoside biosynthesis.Next,we constructed the overexpression vector pCAMBIA3301-PgSQE08-01 and the RNAi vector pART27-PgSQE08-01 and transformed ginseng adventitious roots using Agrobacterium rhizogenes,to obtain positive hairy-root clones.Thereafter,quantitative reverse transcriptionpolymerase chain reaction and high-performance liquid chromatography were used to determine the expression of relevant genes and ginsenoside content,respectively.Then,we focused on the function of PgSQE08-01 gene,which was noted to be involved in ginsenoside biosynthesis.Thus,these findings not only provided a molecular basis for the identification of important functional genes in ginseng but also enriched genetic resources for the biosynthesis of ginsenosides using synthetic biology.
基金supported by the Youth Shihezi University Applied Basic Research Project of China,No.2015ZRKYQ-LH19
文摘Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D（-）-2-amino-5-phosphonopentanoic acid（AP-5）,or both once daily for 15 days.Compared with injured drug na？ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity（as assessed by immunohistochemistry） and protein（as determined by western blot assay） in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.
