Tea plant (Camellia sinensis) has unique biological features for the study of cellular and molecular mechanisms, an evergreen broad-leaved woody plant which can accumulate selenium in soil abundant of Selenium. Expres...Tea plant (Camellia sinensis) has unique biological features for the study of cellular and molecular mechanisms, an evergreen broad-leaved woody plant which can accumulate selenium in soil abundant of Selenium. Expression of the genes related to Selenium (Se) metabolism is an adaptation to the soil environment for a long period. The purpose of the present study was to explore if there exist differences of expression about these genes in tea plant between growing in Selenium-abundant and normal soil. A quantitative real-time reverse transcription polymerase chain reaction (Q-RT-PCR) assay was done for quantification of ATP sulfurylase (APS) and selenocysteine methyltransferase (SMT) mRNA normalized to Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene in tea plant. Young leaves, mature leaves and tender roots from tea plants growing in soil abundant of Selenium were respectively obtained from Shitai County, Anhui Province, and also the relevant materials of the selenium un-enriched tea plant planted at agricultural garden of Ahui Agriculture University were taken as control for real-time PCR analysis. The results showed that APS1, APS2 and SMT expression levels for either young or mature leaves in selenium-enriched tea plant were lower than that in ordinary (selenium un-enriched) tea plant. In contrast, the APS1, APS2 and SMT expression level of roots in selenium-enriched tea plant were all higher than that in ordinary tea plant. APS1 gene expression level of roots in selenium-enriched tea plant was about 1.6 times higher than that in the ordinary tea plant, APS2 gene expression level was about 4.8-fold higher than that in the ordinary tea plant, SMT gene expression level was about 3.3 times higher than that in the ordinary tea plant. Among various tissues of selenium-enriched tea plant, APS1 gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the lowest among them;APS2 gene relative expression level of young leaves was similar to or slightly higher than the roots, and the one of mature leaves was the lowest among them;SMT gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the highest among them. Our results suggest that there existed correlation between selenium and expression levels of these genes.展开更多
二滩电站500 k V系统主接线为3/2与4/3混合接线方式,500 k V GIS设备包括断路器、隔离开关、接地刀、TV、TA、母线、设备互联短引线等。主变压器高压侧T区在倒闸操作中,当处于热备用状态时,一般情况下电压较低,三相电压平衡,约120 k V左...二滩电站500 k V系统主接线为3/2与4/3混合接线方式,500 k V GIS设备包括断路器、隔离开关、接地刀、TV、TA、母线、设备互联短引线等。主变压器高压侧T区在倒闸操作中,当处于热备用状态时,一般情况下电压较低,三相电压平衡,约120 k V左右;有时电压较高,三相电压不平衡,高的约260 k V左右。该现象对运行操作及二次系统产生了影响。分析该现象属于铁磁谐振现象,对其形成原因作了相应分析,并通过仿真得到了验证。展开更多
Terrestrial plants have two to four times more ATP-binding cassette （ABC） transporter genes than other organisms, including their ancestral microalgae. Recent studies found that plants harboring mutations in these t...Terrestrial plants have two to four times more ATP-binding cassette （ABC） transporter genes than other organisms, including their ancestral microalgae. Recent studies found that plants harboring mutations in these transporters exhibit dramatic phenotypes, many of which are related to developmental processes and functions necessary for life on dry land. These results suggest that ABC transporters multiplied during evolution and assumed novel functions that allowed plants to adapt to terrestrial environmental conditions. Examining the literature on plant ABC transporters from this viewpoint led us to propose that diverse ABC transporters enabled many unique and essential aspects of a terrestrial plant＇s lifestyle, by transporting various compounds across specific membranes of the plant.展开更多
文摘Tea plant (Camellia sinensis) has unique biological features for the study of cellular and molecular mechanisms, an evergreen broad-leaved woody plant which can accumulate selenium in soil abundant of Selenium. Expression of the genes related to Selenium (Se) metabolism is an adaptation to the soil environment for a long period. The purpose of the present study was to explore if there exist differences of expression about these genes in tea plant between growing in Selenium-abundant and normal soil. A quantitative real-time reverse transcription polymerase chain reaction (Q-RT-PCR) assay was done for quantification of ATP sulfurylase (APS) and selenocysteine methyltransferase (SMT) mRNA normalized to Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene in tea plant. Young leaves, mature leaves and tender roots from tea plants growing in soil abundant of Selenium were respectively obtained from Shitai County, Anhui Province, and also the relevant materials of the selenium un-enriched tea plant planted at agricultural garden of Ahui Agriculture University were taken as control for real-time PCR analysis. The results showed that APS1, APS2 and SMT expression levels for either young or mature leaves in selenium-enriched tea plant were lower than that in ordinary (selenium un-enriched) tea plant. In contrast, the APS1, APS2 and SMT expression level of roots in selenium-enriched tea plant were all higher than that in ordinary tea plant. APS1 gene expression level of roots in selenium-enriched tea plant was about 1.6 times higher than that in the ordinary tea plant, APS2 gene expression level was about 4.8-fold higher than that in the ordinary tea plant, SMT gene expression level was about 3.3 times higher than that in the ordinary tea plant. Among various tissues of selenium-enriched tea plant, APS1 gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the lowest among them;APS2 gene relative expression level of young leaves was similar to or slightly higher than the roots, and the one of mature leaves was the lowest among them;SMT gene relative expression level of young leaves was similar to or slightly higher than mature leaves, and the one of roots was the highest among them. Our results suggest that there existed correlation between selenium and expression levels of these genes.
文摘二滩电站500 k V系统主接线为3/2与4/3混合接线方式,500 k V GIS设备包括断路器、隔离开关、接地刀、TV、TA、母线、设备互联短引线等。主变压器高压侧T区在倒闸操作中,当处于热备用状态时,一般情况下电压较低,三相电压平衡,约120 k V左右;有时电压较高,三相电压不平衡,高的约260 k V左右。该现象对运行操作及二次系统产生了影响。分析该现象属于铁磁谐振现象,对其形成原因作了相应分析,并通过仿真得到了验证。
文摘Terrestrial plants have two to four times more ATP-binding cassette （ABC） transporter genes than other organisms, including their ancestral microalgae. Recent studies found that plants harboring mutations in these transporters exhibit dramatic phenotypes, many of which are related to developmental processes and functions necessary for life on dry land. These results suggest that ABC transporters multiplied during evolution and assumed novel functions that allowed plants to adapt to terrestrial environmental conditions. Examining the literature on plant ABC transporters from this viewpoint led us to propose that diverse ABC transporters enabled many unique and essential aspects of a terrestrial plant＇s lifestyle, by transporting various compounds across specific membranes of the plant.
