克隆鉴定了一个水稻促分裂原活化蛋白激酶（mitogen-activated protein kinases, MAPK）基因OsMPK4．OsMPK4基因cDNA全长1483bp，包含一个1131bp的开放阅读框，编码一个由376个氨基酸组成的蛋白，预测分子量为42．8kD．OsMPK4基因位于...克隆鉴定了一个水稻促分裂原活化蛋白激酶（mitogen-activated protein kinases, MAPK）基因OsMPK4．OsMPK4基因cDNA全长1483bp，包含一个1131bp的开放阅读框，编码一个由376个氨基酸组成的蛋白，预测分子量为42．8kD．OsMPK4基因位于水稻第10号染色体上，由6个外显子和5个内含子组成．OsMPK4蛋白具有MAPK的11个保守结构域及磷酸化位点TEY模体．系统进化树分析表明，OsMPK4属于B组MAPK成员，与已知水稻MAPK蛋白有56％～74％的一致性．原核表达了OsMPK4基因，纯化获得重组OsMPK4融合蛋白，并构建OsMPK4的转基因双元载体，用于OsMPK4的生化功能及其生物学功能研究．展开更多
In order to clarify the mechanism of action of licorice flavonoids in alleviating bone loss caused by osteoporosis,this study compared the effects of four glycyrrhiza flavonoids,naringenin,liquiritigenin,isoliquiritig...In order to clarify the mechanism of action of licorice flavonoids in alleviating bone loss caused by osteoporosis,this study compared the effects of four glycyrrhiza flavonoids,naringenin,liquiritigenin,isoliquiritigenin,and licochalcone A,on osteogenic differentiation and mineralization by molecular docking simulation,alkaline phosphatase(ALP)activity and osteocalcin(OCN)content assays,and Runt-related transcription factor 2(Runx2)expression,and explored their potential molecular mechanisms.The results of molecular docking showed that the docking score of liquiritigenin with the estrogen receptor(ER)was the highest.All four flavonoids up-regulated ALP activity and OCN concentration in MC3T3-E1 cells,thereby elevating the mineralization level,among which liquiritigenin was the most effective.Moreover,treatment with a phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002)inhibited liquiritigenin from inducing increased phosphorylation levels in the PI3K/protein kinase B(AKT)signaling pathway and up-regulation of Runx2 expression,suggesting that PI3K and AKT were involved in osteogenic action.Liquiritigenin reversed bone mineral density loss in a zebrafish osteoporosis model.These findings suggest that liquiritigenin has the most significant osteogenic effect among the four estrogen-like flavonoids,stimulating osteoblast differentiation and bone mineralization through the activation of Runx2 via the PI3K/AKT signaling pathways.In conclusion,this study highlights the great potential of liquiritigenin for preventing and treating osteoporosis.展开更多
目的观察高渗透压对兔髓核细胞活性的影响及JNK/SAPK(c-Jun N-terminal kinases/stress-activated protein kinases)和p38信号转导通路在此过程中的作用。方法根据不同渗透压及时间段处理髓核细胞将实验分为对照组、刺激组和阻断组后采...目的观察高渗透压对兔髓核细胞活性的影响及JNK/SAPK(c-Jun N-terminal kinases/stress-activated protein kinases)和p38信号转导通路在此过程中的作用。方法根据不同渗透压及时间段处理髓核细胞将实验分为对照组、刺激组和阻断组后采用流式细胞仪检测各组髓核细胞凋亡情况,同时利用免疫荧光和Western blot技术检测磷酸化p38丝裂原活化蛋白激酶(phospho-p38mitogen-activated protein kinases,P-p38MAPK)、磷酸化JNK/SAPK激酶(phospho-JNK/SAPK,P-JNK/SAPK)的亚细胞定位及表达水平,观察其对髓核细胞凋亡的影响。结果高渗透压[600mOsm/kg H2O(mOsm)]可导致髓核细胞显著凋亡及P-p38 MAPK和P-JNK/SAPK蛋白表达水平改变。600mOsm时各刺激组凋亡细胞与对照组相比,差异均有显著统计学意义(P<0.01),而阻断组凋亡细胞明显减少;而400mOsm时各刺激组和阻断组凋亡细胞与对照组相比差异均无统计学意义;免疫荧光结果显示P-p38 MAPK和P-JNK/SAPK在髓核细胞质和细胞核中均有表达;经高渗透压(600mOsm)刺激后P-p38MAPK和P-JNK/SAPK表达均显著高于对照组(P<0.01),而相应阻断组P-p38MAPK和P-JNK/SAPK表达均显著降低。结论高渗透压通过激活JNK/SAPK和p38信号转导通路导致体外培养的兔髓核细胞凋亡,同时髓核细胞对轻度的渗透压升高具有一定的适应性。展开更多
文摘克隆鉴定了一个水稻促分裂原活化蛋白激酶（mitogen-activated protein kinases, MAPK）基因OsMPK4．OsMPK4基因cDNA全长1483bp，包含一个1131bp的开放阅读框，编码一个由376个氨基酸组成的蛋白，预测分子量为42．8kD．OsMPK4基因位于水稻第10号染色体上，由6个外显子和5个内含子组成．OsMPK4蛋白具有MAPK的11个保守结构域及磷酸化位点TEY模体．系统进化树分析表明，OsMPK4属于B组MAPK成员，与已知水稻MAPK蛋白有56％～74％的一致性．原核表达了OsMPK4基因，纯化获得重组OsMPK4融合蛋白，并构建OsMPK4的转基因双元载体，用于OsMPK4的生化功能及其生物学功能研究．
文摘In order to clarify the mechanism of action of licorice flavonoids in alleviating bone loss caused by osteoporosis,this study compared the effects of four glycyrrhiza flavonoids,naringenin,liquiritigenin,isoliquiritigenin,and licochalcone A,on osteogenic differentiation and mineralization by molecular docking simulation,alkaline phosphatase(ALP)activity and osteocalcin(OCN)content assays,and Runt-related transcription factor 2(Runx2)expression,and explored their potential molecular mechanisms.The results of molecular docking showed that the docking score of liquiritigenin with the estrogen receptor(ER)was the highest.All four flavonoids up-regulated ALP activity and OCN concentration in MC3T3-E1 cells,thereby elevating the mineralization level,among which liquiritigenin was the most effective.Moreover,treatment with a phosphatidylinositol-3-kinase(PI3K)inhibitor(LY294002)inhibited liquiritigenin from inducing increased phosphorylation levels in the PI3K/protein kinase B(AKT)signaling pathway and up-regulation of Runx2 expression,suggesting that PI3K and AKT were involved in osteogenic action.Liquiritigenin reversed bone mineral density loss in a zebrafish osteoporosis model.These findings suggest that liquiritigenin has the most significant osteogenic effect among the four estrogen-like flavonoids,stimulating osteoblast differentiation and bone mineralization through the activation of Runx2 via the PI3K/AKT signaling pathways.In conclusion,this study highlights the great potential of liquiritigenin for preventing and treating osteoporosis.
