The 1216bp5’upstream region of the gene encoding the class Ⅲ chitinase VCH3 was isolated from grapevine(Vitis amurensis Rubr．)(Genbank accession number AF441123)and two inverse salicylic acid(SA)responsive cis-acti...The 1216bp5’upstream region of the gene encoding the class Ⅲ chitinase VCH3 was isolated from grapevine(Vitis amurensis Rubr．)(Genbank accession number AF441123)and two inverse salicylic acid(SA)responsive cis-acting motifs(TGACG)were found at-1181bp and-293 bp upstream of the transcriptional start site．respectively．To characterize the vcH3promoter，four chimeric constructs varied in the length of promoter fragments from-1187bp，-892bp，-589bp and-276bpto+7bp relative to the transcriptional start site were placed to the upstream of the β-glucuronidase(GUS)coding region and transferred to Nicotlana tobacum L．CV．NC89 by Agrobacterium tumefaciens-mediated leaf discs transformation．The functional properties of each promoter fragment were examined by fluorometric and histochemical analysis of GUS activity in the transgenic tobacco root treated withSA．The VCH3(-276)GUS construct．containing only the TATA and CAAT boxes was shown to have little inducibility upontreatment with SA．However，the similarly higher level of GUS expression was observed in the VCH3(-589) GUS or VCH3(-892) GUS transgenic plants with only one cis-acting motif,while the most abundance of GUS expression was found in the full-1ength promoter(-1187bpto+7bp)with two cis-acting motifs．The seresults indicated that the twocis-acting motifs werere quired for the maximal expression of the GUS reporter gene by SA induction．In addition，the histochemical analysis of GUS activity showed that the four VCH3 promoter fragments were more active in vascular tissue than that in outer and inner cortexes of the transgenic tobacco roots treated by SA，suggesting that the region involved in vascular tissue-specific expression of VCH3 promoter upon SA inducibility appears to belocated between positions-276 bp and+7bp relative to the transcriptional start site．In general，these results indicate a potential use for the SA induction of VCH3 promoter in genetic engineering．展开更多
Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used ...Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.展开更多
文摘The 1216bp5’upstream region of the gene encoding the class Ⅲ chitinase VCH3 was isolated from grapevine(Vitis amurensis Rubr．)(Genbank accession number AF441123)and two inverse salicylic acid(SA)responsive cis-acting motifs(TGACG)were found at-1181bp and-293 bp upstream of the transcriptional start site．respectively．To characterize the vcH3promoter，four chimeric constructs varied in the length of promoter fragments from-1187bp，-892bp，-589bp and-276bpto+7bp relative to the transcriptional start site were placed to the upstream of the β-glucuronidase(GUS)coding region and transferred to Nicotlana tobacum L．CV．NC89 by Agrobacterium tumefaciens-mediated leaf discs transformation．The functional properties of each promoter fragment were examined by fluorometric and histochemical analysis of GUS activity in the transgenic tobacco root treated withSA．The VCH3(-276)GUS construct．containing only the TATA and CAAT boxes was shown to have little inducibility upontreatment with SA．However，the similarly higher level of GUS expression was observed in the VCH3(-589) GUS or VCH3(-892) GUS transgenic plants with only one cis-acting motif,while the most abundance of GUS expression was found in the full-1ength promoter(-1187bpto+7bp)with two cis-acting motifs．The seresults indicated that the twocis-acting motifs werere quired for the maximal expression of the GUS reporter gene by SA induction．In addition，the histochemical analysis of GUS activity showed that the four VCH3 promoter fragments were more active in vascular tissue than that in outer and inner cortexes of the transgenic tobacco roots treated by SA，suggesting that the region involved in vascular tissue-specific expression of VCH3 promoter upon SA inducibility appears to belocated between positions-276 bp and+7bp relative to the transcriptional start site．In general，these results indicate a potential use for the SA induction of VCH3 promoter in genetic engineering．
基金supported by the National Environmental Protection Public Welfare projects(Nos.201409047 and 201109017)the “13th Five-Year Plan” National Key Research and Development Program of China(No.2016YFC0501108)+1 种基金the Fundamental Research Funds for the Central Universities(No.2016QH02)Beijing Natural Science Foundation(No.8152025)
文摘Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons（VCHs）. Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures（silty,clayey, and sandy soils） along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform（TCM） and trichloroethylene（TCE）. Mechanical soil aeration was effective for remediating VCHs（removal efficiency 〉 98%）. The volatilization process was described by an exponential kinetic function.In the early stage of treatment（0–7 hr）, rapid contaminant volatilization followed a pseudofirst order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8 hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner.
