目的探讨一种小鼠α-(1,2)-岩藻糖基转移酶SEC1基因敲除(SEC1^(-/-))对葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的结肠炎小鼠中结肠炎症和肠道菌群的影响。方法采用CRISPR/Cas9技术构建SEC1^(-/-)C57BL/6小鼠,通过连续口服3%葡...目的探讨一种小鼠α-(1,2)-岩藻糖基转移酶SEC1基因敲除(SEC1^(-/-))对葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的结肠炎小鼠中结肠炎症和肠道菌群的影响。方法采用CRISPR/Cas9技术构建SEC1^(-/-)C57BL/6小鼠,通过连续口服3%葡聚糖硫酸钠5天构建实验性结肠炎模型,设置SEC1^(-/-)结肠炎组(14只)、野生型结肠炎组(15只)和野生型对照组(6只)共3组。通过疾病活动度评分和体质量变化评估结肠炎严重程度,收集小鼠升结肠内粪便样本,采用高通量16s-rDNA测序技术检测粪便菌群组分,通过生物信息分析比较肠道菌群组分的差异。组间比较采用方差分析、独立样本t检验或秩和检验。结果饮用DSS第7天,与野生型结肠炎组比较,SEC1^(-/-)结肠炎小鼠体质量显著下降(77.9%±4.7%vs 87.0%±6.2%,P<0.05),而疾病活动指数显著升高(7.3±2.8 vs 9.4±2.6,P<0.05)。野生型结肠炎小鼠Simpson指数显著低于对照组小鼠(0.83 vs 0.91,P<0.05),但两组小鼠肠道菌群OTU个数、Shannon和chao1指数比较,差异均无统计学意义(P均>0.05)。与野生型结肠炎组比较,SEC1^(-/-)结肠炎组肠道菌群的OTU个数显著增多(305 vs 194,P<0.05),Shannon和chao1指数均显著增加(4.71 vs 4.09;332 vs 207;P均<0.05),乳酸杆菌属(28.95 vs 2.23)、梭菌属(0.13 vs 0.01)和糖单胞菌属(1.82 vs 0.09)的丰度均显著增多(P均<0.05)。结论SEC1基因敲除使葡聚糖硫酸钠诱导的结肠炎小鼠模型严重程度加重,并影响结肠炎小鼠的肠道菌群组成。展开更多
目的探讨IQSEC1是否通过病毒蛋白PB1调控甲型流感病毒的增殖。方法首先克隆甲型流感病毒[A/Shanghai/02/2013(H7N9)]的8个基因;其次,通过免疫共沉淀检测IQ模体Sec7结构域蛋白1(IQSEC1)与聚合酶PB1(PB1)存在相互作用;此外,通过过表达或...目的探讨IQSEC1是否通过病毒蛋白PB1调控甲型流感病毒的增殖。方法首先克隆甲型流感病毒[A/Shanghai/02/2013(H7N9)]的8个基因;其次,通过免疫共沉淀检测IQ模体Sec7结构域蛋白1(IQSEC1)与聚合酶PB1(PB1)存在相互作用;此外,通过过表达或者敲低IQSEC1的方法检测IQSEC1对PB1核定位的影响;最后,过表达或者敲低IQSEC1后检测Influenza A virus[A/Shanghai/02/2013(H7N9)]。结果病毒感染条件下,外源IQSEC1和PB1存在相互作用。当过表达IQSEC1时,细胞中IQSEC1的表达量上升,相应的PB1在细胞核中的定位减少;当用敲低IQSEC1时,细胞中IQSEC1的表达量下降,相应的PB1在细胞核中的定位上升。过表达IQSEC1后,甲型流感病毒的增殖水平下降(P<0.05)。敲低IQSEC1后,甲型流感病毒的增殖水平上升(P<0.05)。结论IQSEC1通过减少甲型流感病毒蛋白PB1的核定位抑制甲型流感病毒的增殖。展开更多
Pollen tube polar growth is a key physiological activity for angiosperms to complete double fertilization, which is highly dependent on the transport of polar substances mediated by secretory vesicles.The exocyst and ...Pollen tube polar growth is a key physiological activity for angiosperms to complete double fertilization, which is highly dependent on the transport of polar substances mediated by secretory vesicles.The exocyst and Sec1/Munc18(SM) proteins are involved in the regulation of the tethering and fusion of vesicles and plasma membranes, but the molecular mechanism by which they regulate pollen tube polar growth is still unclear. In this study, we found that loss of function of SEC1A, a member of the SM protein family in Arabidopsis thaliana, resulted in reducing pollen tube growth and a significant increase in pollen tube width. SEC1A was diffusely distributed in the pollen tube cytoplasm, and was more concentrated at the tip of the pollen tube. Through coimmunoprecipitation-mass spectrometry screening,protein interaction analysis and in vivo microscopy,we found that SEC1A interacted with the exocyst subunit SEC6, and they mutually affected the distribution and secretion rate at the tip of the pollen tube. Meanwhile, the functional loss of SEC1A and SEC6 significantly affected the distribution of the SNARE(soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complex member SYP125 at the tip of the pollen tube, and led to the disorder of pollen tube cell wall components. Genetic analysis revealed that the pollen tube-related phenotype of the sec1a sec6 double mutant was significantly enhanced compared with their respective single mutants. Therefore, we speculated that SEC1A and SEC6 cooperatively regulate the fusion of secretory vesicles and plasma membranes in pollen tubes, thereby affecting the length and the width of pollen tubes.展开更多
文摘目的探讨一种小鼠α-(1,2)-岩藻糖基转移酶SEC1基因敲除(SEC1^(-/-))对葡聚糖硫酸钠(dextran sulphate sodium,DSS)诱导的结肠炎小鼠中结肠炎症和肠道菌群的影响。方法采用CRISPR/Cas9技术构建SEC1^(-/-)C57BL/6小鼠,通过连续口服3%葡聚糖硫酸钠5天构建实验性结肠炎模型,设置SEC1^(-/-)结肠炎组(14只)、野生型结肠炎组(15只)和野生型对照组(6只)共3组。通过疾病活动度评分和体质量变化评估结肠炎严重程度,收集小鼠升结肠内粪便样本,采用高通量16s-rDNA测序技术检测粪便菌群组分,通过生物信息分析比较肠道菌群组分的差异。组间比较采用方差分析、独立样本t检验或秩和检验。结果饮用DSS第7天,与野生型结肠炎组比较,SEC1^(-/-)结肠炎小鼠体质量显著下降(77.9%±4.7%vs 87.0%±6.2%,P<0.05),而疾病活动指数显著升高(7.3±2.8 vs 9.4±2.6,P<0.05)。野生型结肠炎小鼠Simpson指数显著低于对照组小鼠(0.83 vs 0.91,P<0.05),但两组小鼠肠道菌群OTU个数、Shannon和chao1指数比较,差异均无统计学意义(P均>0.05)。与野生型结肠炎组比较,SEC1^(-/-)结肠炎组肠道菌群的OTU个数显著增多(305 vs 194,P<0.05),Shannon和chao1指数均显著增加(4.71 vs 4.09;332 vs 207;P均<0.05),乳酸杆菌属(28.95 vs 2.23)、梭菌属(0.13 vs 0.01)和糖单胞菌属(1.82 vs 0.09)的丰度均显著增多(P均<0.05)。结论SEC1基因敲除使葡聚糖硫酸钠诱导的结肠炎小鼠模型严重程度加重,并影响结肠炎小鼠的肠道菌群组成。
文摘目的探讨IQSEC1是否通过病毒蛋白PB1调控甲型流感病毒的增殖。方法首先克隆甲型流感病毒[A/Shanghai/02/2013(H7N9)]的8个基因;其次,通过免疫共沉淀检测IQ模体Sec7结构域蛋白1(IQSEC1)与聚合酶PB1(PB1)存在相互作用;此外,通过过表达或者敲低IQSEC1的方法检测IQSEC1对PB1核定位的影响;最后,过表达或者敲低IQSEC1后检测Influenza A virus[A/Shanghai/02/2013(H7N9)]。结果病毒感染条件下,外源IQSEC1和PB1存在相互作用。当过表达IQSEC1时,细胞中IQSEC1的表达量上升,相应的PB1在细胞核中的定位减少;当用敲低IQSEC1时,细胞中IQSEC1的表达量下降,相应的PB1在细胞核中的定位上升。过表达IQSEC1后,甲型流感病毒的增殖水平下降(P<0.05)。敲低IQSEC1后,甲型流感病毒的增殖水平上升(P<0.05)。结论IQSEC1通过减少甲型流感病毒蛋白PB1的核定位抑制甲型流感病毒的增殖。
基金supported by the National Natural Science Foundation of China (32170330, 32170331 and 31970195)Hainan Yazhou Bay Seed Lab (B23YQ1510)the Fundamental Research Funds for the Central Universities (lzujbky-2022-ey06)。
文摘Pollen tube polar growth is a key physiological activity for angiosperms to complete double fertilization, which is highly dependent on the transport of polar substances mediated by secretory vesicles.The exocyst and Sec1/Munc18(SM) proteins are involved in the regulation of the tethering and fusion of vesicles and plasma membranes, but the molecular mechanism by which they regulate pollen tube polar growth is still unclear. In this study, we found that loss of function of SEC1A, a member of the SM protein family in Arabidopsis thaliana, resulted in reducing pollen tube growth and a significant increase in pollen tube width. SEC1A was diffusely distributed in the pollen tube cytoplasm, and was more concentrated at the tip of the pollen tube. Through coimmunoprecipitation-mass spectrometry screening,protein interaction analysis and in vivo microscopy,we found that SEC1A interacted with the exocyst subunit SEC6, and they mutually affected the distribution and secretion rate at the tip of the pollen tube. Meanwhile, the functional loss of SEC1A and SEC6 significantly affected the distribution of the SNARE(soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complex member SYP125 at the tip of the pollen tube, and led to the disorder of pollen tube cell wall components. Genetic analysis revealed that the pollen tube-related phenotype of the sec1a sec6 double mutant was significantly enhanced compared with their respective single mutants. Therefore, we speculated that SEC1A and SEC6 cooperatively regulate the fusion of secretory vesicles and plasma membranes in pollen tubes, thereby affecting the length and the width of pollen tubes.
