Fruit firmness is an important quality trait of apple fruit texture,and the pre-harvest ripening period is the key period for the formation of apple fruit texture.Expansin is a cell wall loosing protein family that ha...Fruit firmness is an important quality trait of apple fruit texture,and the pre-harvest ripening period is the key period for the formation of apple fruit texture.Expansin is a cell wall loosing protein family that has four subfamilies:α-expansin(EXPA),β-expansin(EXPB),expansin-like A(EXLA),and expansin-like B(EXLB).In this study,we investigated the key period of pre-harvest texture formation in‘Golden Delicious’apples based on fruit longitudinal diameter,transverse diameter,firmness,tissue structure,respiration intensity,ethylene release rate,and expansin activity.Within the 10 days before harvest,the fruit was found to reach maturity.Semi-quantitative RT-PCR revealed that most of the expansins were expressed at the ripening stage before harvest.The biological function of the EXLB subfamily gene,MdEXLB1,was further identified,and its subcellular localization on the cell wall was confirmed by transient transformation experiments.Compared with the wild type(WT),the transgenic tomato lines overexpressing MdEXLB1 had lower plant height,earlier fruiting period,fewer days for fruit ripening,higher fruit maturity,lower fruit firmness,higher fruit expansin activity,more discrete flesh cell structure,and accelerated fruit ripening process.Overall,this is the first study to propose that the apple EXLB subfamily gene,MdEXLB1,has biological functions and plays an important role in promoting fruit ripening and softening.展开更多
文摘目的 评价不同细胞基质制备的肠道病毒71型（EV71）灭活疫苗上市后常规免疫安全性。 方法 EV71灭活疫苗疑似预防接种异常反应（AEFI）数据来源于中国免疫规划信息管理系统，为2017年接种EV71 灭活疫苗后江苏省报告的监测数据；受种儿童人口学信息和接种剂次数来源于江苏省预防接种信息管理系统。 结果 2017年江苏省共接种EV71灭活疫苗316 889剂，报告AEFI 208例，报告发生率为65.64/10万剂（95% CI ：56.72/10万剂～74.56/10万剂），其中一般反应55.54/10万剂（95% CI ：47.34/10万剂～63.74/10万剂），异常反应 7.89/10万剂（95% CI ：4.80/10万剂～10.98/10万剂）；不同细胞基质的疫苗AEFI发生率（χ 2 =35.61， P ＜0.01）和一般反应发生率（χ 2 =34.09， P ＜0.01）差异有统计学意义，异常反应发生率差异无统计学意义（χ 2 =1.88， P =0.17），均未见严重异常反应，208例AEFI均未住院且均痊愈。EV71灭活疫苗（Vero细胞）首剂接种一般反应发生率高于第二剂（χ 2 =6.94， P ＜0.01），不同季度接种EV71灭活疫苗（人二倍体细胞）一般反应发生率差异有统计学意义（χ 2 =18.86， P ＜0.01）。 结论 不同细胞基质的EV71灭活疫苗在常规免疫接种中AEFI发生率均不高，有良好的安全性；一般反应以发热为主，异常反应以过敏性-荨麻疹、过敏性皮疹和过敏性斑丘疹等过敏性反应为主。
基金the National Key R&D Program of China(2016YFD0201100)the earmarked fund for China Agriculture Research System(CARS-27)+1 种基金the National Natural Science Foundation of China(31672116)the Natural Science Foundation of Hebei Province,China(C2021204134).
文摘Fruit firmness is an important quality trait of apple fruit texture,and the pre-harvest ripening period is the key period for the formation of apple fruit texture.Expansin is a cell wall loosing protein family that has four subfamilies:α-expansin(EXPA),β-expansin(EXPB),expansin-like A(EXLA),and expansin-like B(EXLB).In this study,we investigated the key period of pre-harvest texture formation in‘Golden Delicious’apples based on fruit longitudinal diameter,transverse diameter,firmness,tissue structure,respiration intensity,ethylene release rate,and expansin activity.Within the 10 days before harvest,the fruit was found to reach maturity.Semi-quantitative RT-PCR revealed that most of the expansins were expressed at the ripening stage before harvest.The biological function of the EXLB subfamily gene,MdEXLB1,was further identified,and its subcellular localization on the cell wall was confirmed by transient transformation experiments.Compared with the wild type(WT),the transgenic tomato lines overexpressing MdEXLB1 had lower plant height,earlier fruiting period,fewer days for fruit ripening,higher fruit maturity,lower fruit firmness,higher fruit expansin activity,more discrete flesh cell structure,and accelerated fruit ripening process.Overall,this is the first study to propose that the apple EXLB subfamily gene,MdEXLB1,has biological functions and plays an important role in promoting fruit ripening and softening.
