Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance （R） genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding...Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance （R） genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein（s） to activate plant immune responses at the site of infection. Up to date, over 70 R genes have been isolated from various plant species. Most R proteins contain conserved motifs such as nucleotide-binding site （NBS）, leucine-rich repeat （LRR）, Toll-interleukin-1 receptor domain （TIR, homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor）, coiled-coil （CC） or leucine zipper （LZ） structure and protein kinase domain （PK）. Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity. This review highlights an overview of the recent progress in elucidating the structure, function and evolution of the isolated R genes in different plant-pathogen interaction systems.展开更多
AIM： To investigate dynamic changes and significance of expression of NF-κBp65 in pancreatic tissues of rats with severe acute pancreatitis （SAP）, as well as BN52021 effects. METHODS： Wistar male rats were random...AIM： To investigate dynamic changes and significance of expression of NF-κBp65 in pancreatic tissues of rats with severe acute pancreatitis （SAP）, as well as BN52021 effects. METHODS： Wistar male rats were randomly divided into negative control group （NC group, n = 60）, SAP-model group （SAP group, n = 60）, and BN52021-treated group （BN group, n = 60）, and each of the above groups was respectively divided into 6 subgroups at different time points after operation （1 h, 2 h, 3 h, 6 h, 12 h, and 24 h） （n = 10）. By RT-PCR and Western blot, NF-κBp65 mRNA and its protein expression in pancreatic tissues of rats were detected respectively. RESULTS： The expression of NF-κBp65 mRNA dynamically changed in both SAP groups and BN groups. The mRNA level was higher in SAP groups than NC groups at 2 h, 3 h, 12 h, and 24 h after operation （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and higher in BN groups than SAP group at 1 h （P 〈 0.05）. The NF-κBp65 protein level was higher in SAP groups than NC groups at 1 h, 3 h, and 6 h （P 〈 0.01）, and 2 h, 12 h, and 24 h （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and lower in BN groups than SAP groups at 1 h, 3 h, and 6 h （P 〈 0.05）. CONCLUSION： The expression of NF-κBp65 in pancreatic tissues is dynamically changed and the changes play an important role in pathogenesis of SAR BN52021 exerts therapeutic effects through reducing the expression level of NF-κBp65 protein in the early stage of SAR展开更多
To explore the role of nuclear factor-κB(NF-κB) in the signal pathway of protein kinase C (PKC) regulating the proliferation and apoptosis of T lymphocytes in asthma. T lymphocytes were isolated from the asthmatic m...To explore the role of nuclear factor-κB(NF-κB) in the signal pathway of protein kinase C (PKC) regulating the proliferation and apoptosis of T lymphocytes in asthma. T lymphocytes were isolated from the asthmatic model of guinea pigs and the asthmatic patients. Either the T cells stimulated with PMA alone or those stimulated with PMA together with pyrrolidine dithiocarbamate (PDTC) were incubated for 1 and 24?h. The proliferation of and the presence of NF-κB in the cells incubated for 1?h were observed by MTT and immunohistochemical staining, respectively. And the cells incubated for 24?h were observed for the apoptosis by TUNEL. All the assays were paralleled with controls, and all the data were analyzedstatistically with the software SAS. The percentage of cells of nuclear positive staining of NF-κB and the proliferation of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly higher than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly reduced by PDTC (P<0.01). The apoptosis index of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly lower than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly induced by PDTC (P<0.01). There were good positive correlation between the percentage of cells of nuclear staining of NF-κB of T lymphocytes and the proliferation of T lymphocytes (r=0.51-0.72, P<0.001), and also good negative correlation between the percentage of cells of nuclear staining of NF-κB and the apoptosis index of T lymphocytes (r=-0.55-0.71, P<0.001, respectively). It concludes that the active PKC of asthmatic T lymphocytes promoting the proliferation and inhibiting the apoptosis of T lymphocytes may be mediated by activating NF-κB, the activation of PKC-NF-κB signal pathway of T lymphocytes NF-κB may play an important role in the pathogenesis of asthma.展开更多
Translation initiation sites (TISs) are important signals in cDNA sequences. In many previous attempts to predict TISs in cDNA sequences, three major factors affect the prediction performance: the nature of the cDNA s...Translation initiation sites (TISs) are important signals in cDNA sequences. In many previous attempts to predict TISs in cDNA sequences, three major factors affect the prediction performance: the nature of the cDNA sequence sets, the rel- evant features selected, and the classification methods used. In this paper, we examine different approaches to select and integrate relevant features for TIS pre- diction. The top selected significant features include the features from the position weight matrix and the propensity matrix, the number of nucleotide C in the se- quence downstream ATG, the number of downstream stop codons, the number of upstream ATGs, and the number of some amino acids, such as amino acids A and D. With the numerical data generated from these features, different classifi- cation methods, including decision tree, naive Bayes, and support vector machine, were applied to three independent sequence sets. The identified significant features were found to be biologically meaningful, while the experiments showed promising results.展开更多
基金This work was supported by grants from the Natural Science Foundation of China (No. 30470990, No. 30571063)the"948"Project from the Minister of Agriculture in China, the"973"Project from the Minister of Science and Technology (No.2006CB101904)+1 种基金Hunan Natural Science Foundation (No.06JJ10006)Scientific Research Fund of Hunan Provincial Education department (No.04A024).
文摘Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance （R） genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein（s） to activate plant immune responses at the site of infection. Up to date, over 70 R genes have been isolated from various plant species. Most R proteins contain conserved motifs such as nucleotide-binding site （NBS）, leucine-rich repeat （LRR）, Toll-interleukin-1 receptor domain （TIR, homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor）, coiled-coil （CC） or leucine zipper （LZ） structure and protein kinase domain （PK）. Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity. This review highlights an overview of the recent progress in elucidating the structure, function and evolution of the isolated R genes in different plant-pathogen interaction systems.
基金the National Natural Science Foundation of China, No. 30300465
文摘AIM： To investigate dynamic changes and significance of expression of NF-κBp65 in pancreatic tissues of rats with severe acute pancreatitis （SAP）, as well as BN52021 effects. METHODS： Wistar male rats were randomly divided into negative control group （NC group, n = 60）, SAP-model group （SAP group, n = 60）, and BN52021-treated group （BN group, n = 60）, and each of the above groups was respectively divided into 6 subgroups at different time points after operation （1 h, 2 h, 3 h, 6 h, 12 h, and 24 h） （n = 10）. By RT-PCR and Western blot, NF-κBp65 mRNA and its protein expression in pancreatic tissues of rats were detected respectively. RESULTS： The expression of NF-κBp65 mRNA dynamically changed in both SAP groups and BN groups. The mRNA level was higher in SAP groups than NC groups at 2 h, 3 h, 12 h, and 24 h after operation （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and higher in BN groups than SAP group at 1 h （P 〈 0.05）. The NF-κBp65 protein level was higher in SAP groups than NC groups at 1 h, 3 h, and 6 h （P 〈 0.01）, and 2 h, 12 h, and 24 h （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and lower in BN groups than SAP groups at 1 h, 3 h, and 6 h （P 〈 0.05）. CONCLUSION： The expression of NF-κBp65 in pancreatic tissues is dynamically changed and the changes play an important role in pathogenesis of SAR BN52021 exerts therapeutic effects through reducing the expression level of NF-κBp65 protein in the early stage of SAR
文摘To explore the role of nuclear factor-κB(NF-κB) in the signal pathway of protein kinase C (PKC) regulating the proliferation and apoptosis of T lymphocytes in asthma. T lymphocytes were isolated from the asthmatic model of guinea pigs and the asthmatic patients. Either the T cells stimulated with PMA alone or those stimulated with PMA together with pyrrolidine dithiocarbamate (PDTC) were incubated for 1 and 24?h. The proliferation of and the presence of NF-κB in the cells incubated for 1?h were observed by MTT and immunohistochemical staining, respectively. And the cells incubated for 24?h were observed for the apoptosis by TUNEL. All the assays were paralleled with controls, and all the data were analyzedstatistically with the software SAS. The percentage of cells of nuclear positive staining of NF-κB and the proliferation of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly higher than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly reduced by PDTC (P<0.01). The apoptosis index of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated with PMA were significantly lower than those of T lymphocytes from asthmatic guinea pigs and asthmatic patients stimulated without PMA respectively (P<0.01) and those of T lymphocytes from normal control guinea pigs and normal control persons stimulated with PMA respectively (P<0.01), and were significantly induced by PDTC (P<0.01). There were good positive correlation between the percentage of cells of nuclear staining of NF-κB of T lymphocytes and the proliferation of T lymphocytes (r=0.51-0.72, P<0.001), and also good negative correlation between the percentage of cells of nuclear staining of NF-κB and the apoptosis index of T lymphocytes (r=-0.55-0.71, P<0.001, respectively). It concludes that the active PKC of asthmatic T lymphocytes promoting the proliferation and inhibiting the apoptosis of T lymphocytes may be mediated by activating NF-κB, the activation of PKC-NF-κB signal pathway of T lymphocytes NF-κB may play an important role in the pathogenesis of asthma.
基金This research was supported by Research Grant No.BM/00/007 from the Biomedical Research Council(BMRC)of the Agency for Science,Technology,and Research(A*Star)and the Ministry of Education in Singapore.
文摘Translation initiation sites (TISs) are important signals in cDNA sequences. In many previous attempts to predict TISs in cDNA sequences, three major factors affect the prediction performance: the nature of the cDNA sequence sets, the rel- evant features selected, and the classification methods used. In this paper, we examine different approaches to select and integrate relevant features for TIS pre- diction. The top selected significant features include the features from the position weight matrix and the propensity matrix, the number of nucleotide C in the se- quence downstream ATG, the number of downstream stop codons, the number of upstream ATGs, and the number of some amino acids, such as amino acids A and D. With the numerical data generated from these features, different classifi- cation methods, including decision tree, naive Bayes, and support vector machine, were applied to three independent sequence sets. The identified significant features were found to be biologically meaningful, while the experiments showed promising results.
