Cold shock domain(CSD)-containing proteins are one of the groups of the evolutionarily conserved nucleic acid-binding proteins in all three domains of life consisting of an ancient beta-barrel fold that serves to bind...Cold shock domain(CSD)-containing proteins are one of the groups of the evolutionarily conserved nucleic acid-binding proteins in all three domains of life consisting of an ancient beta-barrel fold that serves to bind nucleic acids.The c DNA of a novel protein-coding gene containing CSD was cloned from Glaciozyma antarctica designated as Ga16676.The full length of Ga16676 gene with the size of 1335 bp encodes for an N-terminal CSD with conserved nucleic acids binding motif RNP1 and RNP2.The Ga16676 gene was cloned in p ET30 Ek/LIC,sequenced,expressed and its resistance towards cold was characterized.Recombinant protein expression of Ga16676 showed overexpressed soluble expression in both supernatant and pellet forms at 20℃.The effects of recombinant CSD protein overexpression on colony formation shows that E.coli cells were able to grow at 37℃and 20℃but not at 4℃while E.coli_Ga16676 cells were able to grow at all temperatures tested.In addition,E.coli_Ga16676 cells showed higher growth rate compared to empty E.coli cells at 10℃.Structural analysis of Ga16676 reveals some interesting findings such as more aromatic interactions for efficient binding in low energy environment,a longer loop that may contribute to structural flexibility and clustering of charged amino acids on the protein surface that is important for protein stability and flexibility.展开更多
Objectives The work intended to reveal the effect of cold shock(CS)treatment on chiling injury(CI),antioxidant capacity.and membrane fatty acid of peach fruit.Materials and methods Peaches were soaked in ice water(10...Objectives The work intended to reveal the effect of cold shock(CS)treatment on chiling injury(CI),antioxidant capacity.and membrane fatty acid of peach fruit.Materials and methods Peaches were soaked in ice water(10℃)for 10 min and stored at 5℃ for 28 d for determination,except CI,and then stored for 3 dat 20℃,only CI was measured.The electrolyte leakage(EL)was measured by conductivity meter.The activities of antioxidant enzymes(superoxide dismutase,ascorbate peroxidase,catalase,and peroxidase)and key enzymes of membrane lipid metabolism(phospho-lipase D,lipase,and lipoxygenase)as well as reactive oxygen species(ROS,O_(2)^(-)and H_(2)O_(2))were measured with a spectrophotometer.An ELISA kit and gas chromatography were used to determine membrane lipids and membrane fatty acids.The relative gene expression was measured by real-time polymerase chain reaction analysis.Results The results showed that CS treatment effectively delayed CI,suppressed the increase of EL and malondialdehyde content.Meanwhile,CS-treated fruit exhibited lower level of ROS and higher activities of antioxidant enzymes.Furthermore,CS treatment inhibited the activities as well as the relative gene expression of key enzymes in membrane lipid metabolism.CS-treated fruits maintained higher membrane fatty acid unsaturation and lower phosphatidic acid content.Conclusions These results indicated that CS treatment effectively lleviated CI and maintained the integrity of cell membranes by inducing antioxidant-related enzyme activity and maintaining a higher ratio of unsaturated fatty acids to saturated fatty acids.展开更多
This paper investigates the comparison problem of the reliability index between a parallel and a cold-standby system,both of which are consisting of two identical units.On the contrary to the general intuitive result,...This paper investigates the comparison problem of the reliability index between a parallel and a cold-standby system,both of which are consisting of two identical units.On the contrary to the general intuitive result,we proved that,under the condition that the system is shocked by a Poisson stream,the life time of the parallel system is longer than that of the cold-standby one in the sense of probability.展开更多
[Objective] This study aimed to investigate the effects of heat shock factor AtHsfAla on programmed cell death in Arabidopsis thaliana under cold stress. [ Method] AtHsfAla-silenced transgenic （NT） and wild-type （W...[Objective] This study aimed to investigate the effects of heat shock factor AtHsfAla on programmed cell death in Arabidopsis thaliana under cold stress. [ Method] AtHsfAla-silenced transgenic （NT） and wild-type （WT） A. thaliana seedlings were used as experimental materials to induce the formation of callus; the callus were cultured to single cells by suspension culture, subjected to cold stress, stained with DAPI, prepared into cell smears and observed under a fluorescence microscope. [ Result] Under cold stress, cell nucleus of wild-type A. thaliana displayed morphological changes, but no apoptotic bodies were found; apoptotic bodies were observed in AtHsfAla-silenced transgenic A. thaliana cells, and the cytoplasm was remarkably concentrated. [ Conclusion] Under cold stress, heat shock factor AtHsfAla exerted inhibitory effects on programmed cell death in A. thaliana, which was of great significance for clarifying the mechanism of stress responses in plants.展开更多
Heat shock protein 70 (Hsp70) is one important member of heat shock protein (Hsp) family that is responsible for various stresses, especially thermal stress. Here we examined the response of Hsp70 gene to both chronic...Heat shock protein 70 (Hsp70) is one important member of heat shock protein (Hsp) family that is responsible for various stresses, especially thermal stress. Here we examined the response of Hsp70 gene to both chronic and acute thermal exposure in Pacific abalone (Haliotis discus hannai Ino). For the chronic exposure, abalones were maintained at 8, 12, 20, and 30°C for four months and their mRNA levels were measured. The highest mRNA level of Hsp70 gene relative to actin gene was detected in the 30°C-acclimated group, followed by the 8°C-acclimated group and then the 12°C- and 20°C-acclimated groups. After the long-term acclimation, gills from each of the above acclimation groups were dissected and exposed to different temperatures between 8°C and 38°C for 30 min. Hsp70 expression in gills acclimated to different temperatures responded differentially to the same temperature exposure. The incubation temperature that induced maximum Hsp70 mRNA expression was higher in the higher temperature acclimation groups than lower temperature groups. Pacific abalones could alter the expression pattern of Hsp70 gene according to environmental thermal conditions, through which they deal with the stress of thermal variations.展开更多
基金the Ministry of Higher Education Malaysia for funding our project(Grant no.FRG0463-2017)。
文摘Cold shock domain(CSD)-containing proteins are one of the groups of the evolutionarily conserved nucleic acid-binding proteins in all three domains of life consisting of an ancient beta-barrel fold that serves to bind nucleic acids.The c DNA of a novel protein-coding gene containing CSD was cloned from Glaciozyma antarctica designated as Ga16676.The full length of Ga16676 gene with the size of 1335 bp encodes for an N-terminal CSD with conserved nucleic acids binding motif RNP1 and RNP2.The Ga16676 gene was cloned in p ET30 Ek/LIC,sequenced,expressed and its resistance towards cold was characterized.Recombinant protein expression of Ga16676 showed overexpressed soluble expression in both supernatant and pellet forms at 20℃.The effects of recombinant CSD protein overexpression on colony formation shows that E.coli cells were able to grow at 37℃and 20℃but not at 4℃while E.coli_Ga16676 cells were able to grow at all temperatures tested.In addition,E.coli_Ga16676 cells showed higher growth rate compared to empty E.coli cells at 10℃.Structural analysis of Ga16676 reveals some interesting findings such as more aromatic interactions for efficient binding in low energy environment,a longer loop that may contribute to structural flexibility and clustering of charged amino acids on the protein surface that is important for protein stability and flexibility.
基金supported by the National Natural Science Foundation of China (No.31972125)the Fundamental Research Funds for the Central Universities (KYYJ201908),China.
文摘Objectives The work intended to reveal the effect of cold shock(CS)treatment on chiling injury(CI),antioxidant capacity.and membrane fatty acid of peach fruit.Materials and methods Peaches were soaked in ice water(10℃)for 10 min and stored at 5℃ for 28 d for determination,except CI,and then stored for 3 dat 20℃,only CI was measured.The electrolyte leakage(EL)was measured by conductivity meter.The activities of antioxidant enzymes(superoxide dismutase,ascorbate peroxidase,catalase,and peroxidase)and key enzymes of membrane lipid metabolism(phospho-lipase D,lipase,and lipoxygenase)as well as reactive oxygen species(ROS,O_(2)^(-)and H_(2)O_(2))were measured with a spectrophotometer.An ELISA kit and gas chromatography were used to determine membrane lipids and membrane fatty acids.The relative gene expression was measured by real-time polymerase chain reaction analysis.Results The results showed that CS treatment effectively delayed CI,suppressed the increase of EL and malondialdehyde content.Meanwhile,CS-treated fruit exhibited lower level of ROS and higher activities of antioxidant enzymes.Furthermore,CS treatment inhibited the activities as well as the relative gene expression of key enzymes in membrane lipid metabolism.CS-treated fruits maintained higher membrane fatty acid unsaturation and lower phosphatidic acid content.Conclusions These results indicated that CS treatment effectively lleviated CI and maintained the integrity of cell membranes by inducing antioxidant-related enzyme activity and maintaining a higher ratio of unsaturated fatty acids to saturated fatty acids.
文摘This paper investigates the comparison problem of the reliability index between a parallel and a cold-standby system,both of which are consisting of two identical units.On the contrary to the general intuitive result,we proved that,under the condition that the system is shocked by a Poisson stream,the life time of the parallel system is longer than that of the cold-standby one in the sense of probability.
基金Supported by National Natural Science Foundation of China(31260061,31060039)Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province(GXZD201601)+1 种基金Key Discipline Construction Project of Kunming UniversityNational College Students Innovation Project of China
文摘[Objective] This study aimed to investigate the effects of heat shock factor AtHsfAla on programmed cell death in Arabidopsis thaliana under cold stress. [ Method] AtHsfAla-silenced transgenic （NT） and wild-type （WT） A. thaliana seedlings were used as experimental materials to induce the formation of callus; the callus were cultured to single cells by suspension culture, subjected to cold stress, stained with DAPI, prepared into cell smears and observed under a fluorescence microscope. [ Result] Under cold stress, cell nucleus of wild-type A. thaliana displayed morphological changes, but no apoptotic bodies were found; apoptotic bodies were observed in AtHsfAla-silenced transgenic A. thaliana cells, and the cytoplasm was remarkably concentrated. [ Conclusion] Under cold stress, heat shock factor AtHsfAla exerted inhibitory effects on programmed cell death in A. thaliana, which was of great significance for clarifying the mechanism of stress responses in plants.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (Nos. 2006AA10A407, 2012AA100812)
文摘Heat shock protein 70 (Hsp70) is one important member of heat shock protein (Hsp) family that is responsible for various stresses, especially thermal stress. Here we examined the response of Hsp70 gene to both chronic and acute thermal exposure in Pacific abalone (Haliotis discus hannai Ino). For the chronic exposure, abalones were maintained at 8, 12, 20, and 30°C for four months and their mRNA levels were measured. The highest mRNA level of Hsp70 gene relative to actin gene was detected in the 30°C-acclimated group, followed by the 8°C-acclimated group and then the 12°C- and 20°C-acclimated groups. After the long-term acclimation, gills from each of the above acclimation groups were dissected and exposed to different temperatures between 8°C and 38°C for 30 min. Hsp70 expression in gills acclimated to different temperatures responded differentially to the same temperature exposure. The incubation temperature that induced maximum Hsp70 mRNA expression was higher in the higher temperature acclimation groups than lower temperature groups. Pacific abalones could alter the expression pattern of Hsp70 gene according to environmental thermal conditions, through which they deal with the stress of thermal variations.
