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Background and Objectives: Salinity stress is a very serious threat to most agricultural products in the world. In the world, rice ranks second after wheat and is a relatively sensitive plant to salt stress. Protein kinases are an important group of kinase enzymes that phosphorylate target proteins by adding phosphate groups. These enzymes play an important role in cell communication by inducing the message of growth and reproduction. Gene expression is a process during which a useful gene product is synthesized by the information obtained from a gene. The purpose of this research was to investigate the expression level of SAPK1 gene from the protein kinase gene group in rice plants under sodium chloride salt stress by examining three different times after the stress was applied. Materials and methods: In this study, the expression pattern of SAPK1 gene in two Cultivars tolerant (Shastak Mohammadi) and sensitive (IR29) of rice plant under salt stress was investigated by factorial experiment in the form of a completely randomized design with three replications. Cultivars were planted in the research greenhouse of the Faculty of Agriculture of Lorestan University and at the seedling stage (5 to 6 leaves), salinity stress was applied to the plant at three levels of 3, 6, and 9 dS/m and the control treatment (without salt stress). Then, at three different times (6, 12, and 24 hours after applying stress), plant leaves were sampled to investigate gene expression. The leaf samples were stored in a freezer at -80 ºC. Then, RNA extraction and cDNA synthesis were done by special kits for each stage, and finally, gene expression analysis was done by qPCR technique and by Livak formula. Results: The results of the analysis of SAPK1 gene expression pattern showed that in both tolerant and sensitive cultivars, the highest level of gene expression was observed at the salinity level of 9 dS/m, 24 hours after applying the stress. At different times after applying the stress in the control treatment and the salinity level of 3 dS/m, the gene expression level in both tolerant and sensitive cultivars did not show any difference and was very insignificant. However, at the salinity level of 6 dS/m, 6 hours after applying the stress, the gene expression level in the tolerant cultivar increased 3 fold compared to the sensitive cultivar and control treatment. At this level, examining gene expression 12 and 24 hours after applying the stress, the amount of gene expression in the tolerant cultivar was about 7 fold higher than the sensitive cultivar and the control treatment. At the salinity level of 9 dS/m, 6 hours after applying the stress, the gene expression level in the tolerant cultivar was doubled compared to the sensitive cultivar and 4 fold higher than the control treatment. While 12 hours after applying the stress, the gene expression level in the tolerant cultivar increased by 5.5 fold compared to the sensitive cultivar and by 10 fold compared to the control treatment. Also, 24 hours after applying the stress, gene expression in the tolerant cultivar was 3.5 fold higher than the sensitive cultivar and 11 fold higher than the control treatment. Conclusion: These results showed that the expression of SAPK1 gene increases in rice plants with increasing salinity levels. Also, investigating the effect of time after applying stress on SAPK1 gene expression, it was found that in the early hours after applying stress, the amount of gene expression was low, but with increasing time up to 24 hours, gene expression in tolerant cultivar increased. These results can be used in molecular studies of rice cultivars to select the most tolerant rice cultivars to salinity stress for cultivation in areas prone to salinity. [ABSTRACT FROM AUTHOR]

Introduction: Protein kinase causes many diseases, including cancer; therefore, inhibiting them plays an important role in the treatment of many diseases. Traditional discovery inhibitors of this enzyme is a time-consuming and costly process. Finding a reliable computer-aided drug discovery tools which can detect the inhibitors will reduce the cost. In this study, it is attempted to separate kinase inhibitors into two groups, active and inactive, using artificial neural network and finally predict biological activities of the predicted active compounds by partial least square . Method: In this study, after extracting the molecular descriptors in order to avoid overfitting problem, dimensional reduction was applied using Genetic algorithm. Moreover, artificial neural network was applied to distinguish active compounds from inactive ones and the biological activities of the small molecules were predicted using partial least square linear regression. Results: The results show that accuracy of the Neural networkmodel was improved from 74.45% to 86.7%, after reducing molecular descriptor dimensions. . The number of hidden nodes of this model was six with 86.7% accuracy, 83.4% sensitivity, 89.6% specificity and 73.2% Mathew's correlation coefficient. Moreover the partial least square linear regression model predicts the biological activity valuesby 85.8% correlation. Conclusion: The Neural network model and the partial least square linear regression model can sufficiently predict Kinase inhibitors and Genetic algorithm will improve the models performance

Background and Objective: Alzheimer's disease (AD) is one of the most common neurodegenerative diseases and results from the extracellular accumulation of -amyloid peptides and the resulting neuronal dysfunction. In this study, the role of nicotinic acetylcholine receptors, protein kinase B (PKB) and protein kinase M (PKM) were evaluated in order to examine the mechanism of the protective effects of rosmarinic acid in a rat model of Alzheimer's disease. Materials and Methods: Animals were divided into 6 groups consisting of 1) Sham, 2) Beta amyloid, 3) Rosmarinic acid pretreated beta amyloid (25 mg/kg), 4-6) Rosmarinic acid and PKM inhibitor, PKB inhibitor and acetylcholine receptor inhibitor pretreated beta amyloid. Two weeks post-surgery, behavioral (alternation percent in Y maze and step through latency in passive avoidance task) and histochemical (hippocampal malondialdehyde and neuronal density measurement) studies were performed. Results: Pretreatment of beta amyloid animals with rosmarinic acid considerably alleviated the behavioral and histochemical disturbances related to the hippocampus. In this group, nicotinic acetylcholine receptors and PKB inhibitors decreased step through latency (p<0.001) and increased hippocampal malondialdehyde levels (p<0.001). In addition, PKB inhibitors decreased hippocampal neuronal density in rosmarinic acid pretreated beta amyloid rats (p<0.05). Conclusion: Based on the findings of this study, it seems that in this experimental model of Alzheimer's disease the protective effects of rosmarinic acid were derived from its antioxidant properties and partially via nicotinic acetylcholine receptors, PKB and PKM. [ABSTRACT FROM AUTHOR]