The presence ofBiecheleria cincta （=Woloszynskia cincta） in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle （EAV...The presence ofBiecheleria cincta （=Woloszynskia cincta） in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle （EAV） were visible in the epicone, and both the hypocone and the cingulum had three series of vesicles each. Thin sections revealed that B. cincta possesses stalked pyrenoids and an unusual eyespot consisting of a stack of cistemae with brick-like materials （type E）, thus supporting its transfer from Woloszynskia to Biecheleria. Spiny cysts formed spontaneously in culture, with an encystment rate of around 20%. Both large subunit ribosomal DNA （LSU rDNA） and internal transcribed spacer region （ITS） sequences in 12 strains from the Chinese coasts were determined. Phylogenetic analyses based on LSU rDNA and ITS sequences using Bayesian inference and maximum likelihood revealed two distinct ribotypes （referred to as ribotype A and B） in B. cincta. ITS region pairwise distances within B. eincta ranged from 0.024 to 0.072, suggesting the existence of a complex of cryptic species.展开更多
Objective To study the chemical constituents of Swertia cincta. Methods Preparative liquid chromatography was employed. The structures of the compounds were elucidated by spectroscopic analysis. isolated from S. cinct...Objective To study the chemical constituents of Swertia cincta. Methods Preparative liquid chromatography was employed. The structures of the compounds were elucidated by spectroscopic analysis. isolated from S. cincta and identified as Results Three secoiridoid glycosides were 8-methoxyl-eustomorusside （1）, secoiridoids eustomorusside （2）, and eustomoside （3）. Conclusion Compound 1 is a new secoiridoid glycoside. Compounds 2 and 3 are isolated from this plant for the first time.展开更多
Objective To study the chemical constituents from the whole plant of Swertia cincta.Methods The chemical constituents were purified by chromatographic methods such as silica gel column and Sephadex LH-20. The structur...Objective To study the chemical constituents from the whole plant of Swertia cincta.Methods The chemical constituents were purified by chromatographic methods such as silica gel column and Sephadex LH-20. The structures of these compounds were elucidated by MS, IR, and NMR analyses. Results Two compounds were isolated from S. cincta. Conclusion Compound 1 is a new compound named swercinctlactone A. Compound 2 is identified as（±）-gentiolactone and its configuration is confirmed by single crystal X-ray diffraction and optical specific rotation.展开更多
Following the genomics revolution, our knowledge of the molecular mechanisms underlying defenses against stress has been greatly expanded. Under strong selective pressure many animals may evolve an enhanced stress tol...Following the genomics revolution, our knowledge of the molecular mechanisms underlying defenses against stress has been greatly expanded. Under strong selective pressure many animals may evolve an enhanced stress tolerance. This can be achieved by altering the structure of proteins （through mutations in the coding regions of genes） or by altering the amount of protein （through changes in transcriptional regulation）. The latter type of evolution can be achieved by substitutions in the promoter of the gene of interest （cisregulatory change） or by altering the structure or amount of transcriptional regulator proteins （trans-regulatory change）. The metallothionein system is one of the best studied stress response systems in the context of heavy metals. Metallothionein expression is assumed to be regulated by metal transcription factor 1 （MTF-1）; however, up to now the involvement of MTF- 1 has only been proven for some vertebrates and Drosophila. Data on invertebrates such as nematodes and earthworms suggest that other mechanisms of metallothionein induction may be present. A detailed study of Cd tolerance was done for a species of soilliving springtail, Orchesella cincta. The metallothionein gene of this species is overexpressed in metal-exposed field populations. Analysis of the metallothionein promoter has demon- strated extensive polymorphisms that have a fimctional significance, as shown in bioreporter assays. In a study comparing 20 different populations, the frequency of a high-expresser promoter allele was positively correlated with the concentration of metals in soil, especially Cd. The springtail study shows that cis-regulatory change of genes involved in the cellular stress response may contribute to evolution of metal tolerance.展开更多
基金Supported by the National Scientific-Basic Special Fund(No.2009FY210400)
文摘The presence ofBiecheleria cincta （=Woloszynskia cincta） in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle （EAV） were visible in the epicone, and both the hypocone and the cingulum had three series of vesicles each. Thin sections revealed that B. cincta possesses stalked pyrenoids and an unusual eyespot consisting of a stack of cistemae with brick-like materials （type E）, thus supporting its transfer from Woloszynskia to Biecheleria. Spiny cysts formed spontaneously in culture, with an encystment rate of around 20%. Both large subunit ribosomal DNA （LSU rDNA） and internal transcribed spacer region （ITS） sequences in 12 strains from the Chinese coasts were determined. Phylogenetic analyses based on LSU rDNA and ITS sequences using Bayesian inference and maximum likelihood revealed two distinct ribotypes （referred to as ribotype A and B） in B. cincta. ITS region pairwise distances within B. eincta ranged from 0.024 to 0.072, suggesting the existence of a complex of cryptic species.
基金NSFC(NO.21262048)Youth Foundation of Lincang Teachers’College(LCSZL201204)
文摘Objective To study the chemical constituents of Swertia cincta. Methods Preparative liquid chromatography was employed. The structures of the compounds were elucidated by spectroscopic analysis. isolated from S. cincta and identified as Results Three secoiridoid glycosides were 8-methoxyl-eustomorusside （1）, secoiridoids eustomorusside （2）, and eustomoside （3）. Conclusion Compound 1 is a new secoiridoid glycoside. Compounds 2 and 3 are isolated from this plant for the first time.
基金National Natural Science Foundation of China(21262048)University Science and Technology Innovation Team of Yunnan Province(IRTSTYN 2014-11)
文摘Objective To study the chemical constituents from the whole plant of Swertia cincta.Methods The chemical constituents were purified by chromatographic methods such as silica gel column and Sephadex LH-20. The structures of these compounds were elucidated by MS, IR, and NMR analyses. Results Two compounds were isolated from S. cincta. Conclusion Compound 1 is a new compound named swercinctlactone A. Compound 2 is identified as（±）-gentiolactone and its configuration is confirmed by single crystal X-ray diffraction and optical specific rotation.
文摘Following the genomics revolution, our knowledge of the molecular mechanisms underlying defenses against stress has been greatly expanded. Under strong selective pressure many animals may evolve an enhanced stress tolerance. This can be achieved by altering the structure of proteins （through mutations in the coding regions of genes） or by altering the amount of protein （through changes in transcriptional regulation）. The latter type of evolution can be achieved by substitutions in the promoter of the gene of interest （cisregulatory change） or by altering the structure or amount of transcriptional regulator proteins （trans-regulatory change）. The metallothionein system is one of the best studied stress response systems in the context of heavy metals. Metallothionein expression is assumed to be regulated by metal transcription factor 1 （MTF-1）; however, up to now the involvement of MTF- 1 has only been proven for some vertebrates and Drosophila. Data on invertebrates such as nematodes and earthworms suggest that other mechanisms of metallothionein induction may be present. A detailed study of Cd tolerance was done for a species of soilliving springtail, Orchesella cincta. The metallothionein gene of this species is overexpressed in metal-exposed field populations. Analysis of the metallothionein promoter has demon- strated extensive polymorphisms that have a fimctional significance, as shown in bioreporter assays. In a study comparing 20 different populations, the frequency of a high-expresser promoter allele was positively correlated with the concentration of metals in soil, especially Cd. The springtail study shows that cis-regulatory change of genes involved in the cellular stress response may contribute to evolution of metal tolerance.
