目的分析CCDC115(Coiled-Coil Domain-Containing Protein 115)的蛋白性质,利用Ccdc115基因缺失的小鼠单核巨噬细胞白血病细胞(RAW264.7),探究CCDC115对胞内鼠伤寒沙门菌生存的影响,为开展CCDC115功能研究及调控胞内沙门菌生存的机制研...目的分析CCDC115(Coiled-Coil Domain-Containing Protein 115)的蛋白性质,利用Ccdc115基因缺失的小鼠单核巨噬细胞白血病细胞(RAW264.7),探究CCDC115对胞内鼠伤寒沙门菌生存的影响,为开展CCDC115功能研究及调控胞内沙门菌生存的机制研究提供理论基础。方法采用生物信息学分析,对CCDC115的基本性质进行探究。依据CRISPR/Cas9基因编辑技术构建RAW264.7-Ccdc115-KO细胞系。将鼠伤寒沙门菌感染RAW264.7及RAW264.7-Ccdc115-KO细胞,通过RT-qRCR、Western Blot、CFU(Colony-Forming Units)计数、酸化成像研究CCDC115在鼠伤寒沙门菌胞内生存中的作用。结果CCDC115是由2个α螺旋及中间无序区组成的不稳定蛋白,无跨膜结构域。成功构建敲除Ccdc115基因的RAW264.7细胞系。鼠伤寒沙门菌感染细胞后,在RAW264.7细胞中mRNA水平和蛋白水平CCDC115表达增加,并且在RAW264.7-Ccdc115-KO细胞内增殖数量是RAW264.7细胞的1.5倍。在吞噬体酸化成像中,鼠伤寒沙门菌吞噬体在RAW264.7细胞中发生酸化,而在RAW264.7-Ccdc115-KO细胞中没有发生酸化。结论成功构建RAW264.7-Ccdc115-KO细胞系;CCDC115在鼠伤寒沙门菌感染过程中表达增加,并可能通过使吞噬体发生酸化抑制鼠伤寒沙门菌在细胞内生存。展开更多
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou...Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.展开更多
G115 steel was jointly developed by China Iron & Steel Research Institute Group Co.,Ltd.and Baosteel for usage in 600-650 ℃ ultrasupercritical boiler tubes.Using a hot extruded G115 tube,creep tests were conducte...G115 steel was jointly developed by China Iron & Steel Research Institute Group Co.,Ltd.and Baosteel for usage in 600-650 ℃ ultrasupercritical boiler tubes.Using a hot extruded G115 tube,creep tests were conducted under a constant stress of 130 MPa and temperatures of 625,650 and 675 ℃.Comparing creep curves under different temperatures,it is observed that the creep performance of a G115 tube is more sensitive to temperature than stress.Steady-state creep rates of creep specimens are significantly increased by enhancing the temperature.A micro-structural analysis of ruptured creep specimens under a stress of 130 MPa and temperatures of 650 ℃ and 675 ℃ was performed;the fracture mechanism of creep specimens under these two temperatures mainly included the appearance of creep holes on the grain boundary and a decrease in the martensite lath density.展开更多
基金supported by grants from the Natural Science Foundation of Hebei Province(Grant No.C2022204086)the Hebei Apple Innovation Team of Modern Agricultural Industry Technology System(Grant No.HBCT2021100211)the National Natural Science Foundation of China(Grant No.32072524).
文摘Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.
文摘G115 steel was jointly developed by China Iron & Steel Research Institute Group Co.,Ltd.and Baosteel for usage in 600-650 ℃ ultrasupercritical boiler tubes.Using a hot extruded G115 tube,creep tests were conducted under a constant stress of 130 MPa and temperatures of 625,650 and 675 ℃.Comparing creep curves under different temperatures,it is observed that the creep performance of a G115 tube is more sensitive to temperature than stress.Steady-state creep rates of creep specimens are significantly increased by enhancing the temperature.A micro-structural analysis of ruptured creep specimens under a stress of 130 MPa and temperatures of 650 ℃ and 675 ℃ was performed;the fracture mechanism of creep specimens under these two temperatures mainly included the appearance of creep holes on the grain boundary and a decrease in the martensite lath density.
