Nanoplastic(NP)contaminants are receiving increasing attention due to the harm they can cause to aquatic organisms and their accumulation in the human body through the food web.The goal of this study was to evaluate t...Nanoplastic(NP)contaminants are receiving increasing attention due to the harm they can cause to aquatic organisms and their accumulation in the human body through the food web.The goal of this study was to evaluate the oxidative stress caused by NPs on the clams Meretrix meretrix and Sinonovacula constricta.Specimens were exposed to three concentrations of fluorescently labeled polystyrene NPs(PS-NPs;0,0.1,and 1 mg L^(-1))for 7 d followed by a 3 d recovery period.The activities of antioxidant enzymes,such as catalase(CAT),superoxide dismutase(SOD),glutathione peroxidase(GPx)and the content of malonaldehyde(MDA)were measured in the digestive gland,gills,and mantle tissues.Results showed that the SOD activity in the gills of M.meretrix was significantly higher than that of the control at day 1,and PS-NPs exposure inhibited the CAT activity in the gills and SOD and GPx activities in the mantle.Exposure to low or high concentrations of PS-NPs increased the activities of both CAT and GPx in the gills of S.constricta at day 3.The oxidative damage was more severe in the digestive gland of M.meretrix and in the mantle of S.constricta based on MDA level,and it returned to normal after recovery.Integrated biomarker response,index version 2(IBRv2)values showed that the gills were more sensitive to PS-NPs than mantle and digestive gland.Therefore,the oxidative stress by PS-NPs depended on exposure time,dose,organ,and species.展开更多
采用SMART(switching metchanism at 5’end of RNA transcript)技术构建缢蛏cDNA基因文库。并对cDNA文库的滴度,重组率和插入片段的大小进行了检测。结果表明,该cDNA文库的滴度为5.50×104cfu/ml,重组率为92.5%,插入片段的长度大多...采用SMART(switching metchanism at 5’end of RNA transcript)技术构建缢蛏cDNA基因文库。并对cDNA文库的滴度,重组率和插入片段的大小进行了检测。结果表明,该cDNA文库的滴度为5.50×104cfu/ml,重组率为92.5%,插入片段的长度大多在1kb以上。对478个克隆子进行了测序,共得到430个有效序列,其中166个序列无同源性,264条序列具有同源性。从中得到肌动蛋白(actin)cDNA的全长1538bp,开放阅读框(ORF)为1131bp,编码376个氨基酸,其预测蛋白的分子量为41.78kD,等电点为5.30。该氨基酸序列与其它物种的同源性大都在90%以上。展开更多
文摘为探讨缢蛏(Sinonovacula constricta)耐受高硫化物环境的分子机理,利用RNA-seq技术开展395μmol/L硫化物胁迫0 h、6 h和96 h缢蛏鳃转录组动态变化的研究,构建9个转录组文库,获得27.09 Gb有效数据,组装得到65747条Unigenes,平均长度为971.46 bp,N50达到1434 bp,注释得到22921条Unigenes。按照FPKM值获得基因表达丰度后,采用DEGseq软件进行差异表达分析,分别在6 h vs.0 h、96 h vs.0 h和96 h vs.6 h组中获得61138、60912和62824条DEGs。按照DEGs筛选阈值,分别在6 h vs.0 h、96 h vs.0 h和96 h vs.6 h组中获得17、10和12个高表达DEGs。KEGG分析显示差异基因(DEGs)显著富集到硫代谢通路,发现高表达的硫醌氧化还原酶基因(SQR),推测线粒体硫化物氧化是其解毒的关键。GO、KEGG分析发现DEGs分别富集到呼吸电子传递链(ETC)及氧化磷酸化通路,细胞色素b的表达显著下调,可能引发线粒体氧化呼吸链受阻,从而产生过量ROS,以激活机体的应激反应。DEGs还富集到转移含磷基团的转移酶活性、核小体组装等GO类别,推测ROS造成DNA氧化损伤后,机体通过DNA复制、组装新染色体以维持遗传物质稳定。采用qRT-PCR进行差异基因组蛋白(H2B)、漆酶(LAC)的响应研究,结果呈时间依赖性的表达模式,推测H2B通过修复受损DNA并增强免疫能力、LAC通过清除ROS以提高机体硫化物抗性。研究结果系统解析了缢蛏耐硫的分子调控机理,为缢蛏耐硫新品种的遗传育种研究奠定了理论基础。
基金supported by the Natural Natural Science Foundation of China(No.41706142)the Earmarked Fund for CARS-49(No.CARS-49).
文摘Nanoplastic(NP)contaminants are receiving increasing attention due to the harm they can cause to aquatic organisms and their accumulation in the human body through the food web.The goal of this study was to evaluate the oxidative stress caused by NPs on the clams Meretrix meretrix and Sinonovacula constricta.Specimens were exposed to three concentrations of fluorescently labeled polystyrene NPs(PS-NPs;0,0.1,and 1 mg L^(-1))for 7 d followed by a 3 d recovery period.The activities of antioxidant enzymes,such as catalase(CAT),superoxide dismutase(SOD),glutathione peroxidase(GPx)and the content of malonaldehyde(MDA)were measured in the digestive gland,gills,and mantle tissues.Results showed that the SOD activity in the gills of M.meretrix was significantly higher than that of the control at day 1,and PS-NPs exposure inhibited the CAT activity in the gills and SOD and GPx activities in the mantle.Exposure to low or high concentrations of PS-NPs increased the activities of both CAT and GPx in the gills of S.constricta at day 3.The oxidative damage was more severe in the digestive gland of M.meretrix and in the mantle of S.constricta based on MDA level,and it returned to normal after recovery.Integrated biomarker response,index version 2(IBRv2)values showed that the gills were more sensitive to PS-NPs than mantle and digestive gland.Therefore,the oxidative stress by PS-NPs depended on exposure time,dose,organ,and species.
文摘采用SMART(switching metchanism at 5’end of RNA transcript)技术构建缢蛏cDNA基因文库。并对cDNA文库的滴度,重组率和插入片段的大小进行了检测。结果表明,该cDNA文库的滴度为5.50×104cfu/ml,重组率为92.5%,插入片段的长度大多在1kb以上。对478个克隆子进行了测序,共得到430个有效序列,其中166个序列无同源性,264条序列具有同源性。从中得到肌动蛋白(actin)cDNA的全长1538bp,开放阅读框(ORF)为1131bp,编码376个氨基酸,其预测蛋白的分子量为41.78kD,等电点为5.30。该氨基酸序列与其它物种的同源性大都在90%以上。
