半乳糖凝集素(Galectin)作为动物凝集素家族的一员,是一种重要的免疫因子,在脊椎动物和无脊椎动物中都参与了重要的免疫防御反应。为明确魁蚶(Scapharca broughtonii)半乳糖凝集素基因的结构特征、组织分布及其对病原菌刺激的免疫反应规...半乳糖凝集素(Galectin)作为动物凝集素家族的一员,是一种重要的免疫因子,在脊椎动物和无脊椎动物中都参与了重要的免疫防御反应。为明确魁蚶(Scapharca broughtonii)半乳糖凝集素基因的结构特征、组织分布及其对病原菌刺激的免疫反应规律,本研究从构建的魁蚶转录组文库中筛选得到半乳糖凝集素基因部分序列,通过c DNA末端快速扩增(rapid amplication of c DNA ends,RACE)技术获得该基因c DNA全长序列(命名为Sb Gal)。序列和结构分析表明,该c DNA全长3120bp,编码554个氨基酸,是一个含有4个糖识别结构域(CRD)的且在双壳贝类中较为独特的半乳糖凝集素;预测蛋白的分子量(Mw)为63.3158 k Da,理论等电点(p I)为4.99。同源性及系统分析表明,Sb Gal基因与美洲牡蛎、合浦珠母贝、海湾扇贝galectin的同源性分别为70%、65%、46%,Sb Gal基因四个CRD彼此的相似性为36%—41%。实时荧光定量PCR(q RT-PCR)结果表明:Sb Gal m RNA在魁蚶血细胞、斧足、闭壳肌、外套膜、鳃和肝胰腺中均有表达,血细胞中的表达量最高,在肝胰腺中的表达量最低;注射鳗弧菌后,相对于对照组,Sb Gal基因在所检测的每个组织中m RNA水平上的表达量都显著上调(P<0.01),而且表达量具有显著的时间依赖性和瞬时表达趋势,呈现先升高后降低的趋势。展开更多
Ocean warming is altering the habitats of marine invertebrates,which has resulted in an increased physiological stress to marine molluscs,especially those intertidal bivalves,such as the ark shell Scapharca broughtoni...Ocean warming is altering the habitats of marine invertebrates,which has resulted in an increased physiological stress to marine molluscs,especially those intertidal bivalves,such as the ark shell Scapharca broughtonii.We investigated the physiological and transcriptional responses of ark shells to acute and chronic thermal stress results showed that at 33℃,a significantly higher cumulative mortality(55.7%)occurred under acute thermal stress than chronic thermal stress.The apoptosis rate of hemocytes was sustained at higher levels and the necrosis rate was increased significantly in a time-dependent manner under acute thermal stress.However,under chronic thermal stress,the apoptosis and necrosis rates exhibited similar change trends:a rapid increase followed by a gradual decline and sustained at a relatively high level until the end of the experiment.The expressions of heat shock protein genes(HSP20 and HSP90),apoptosis-related genes(TRAF6,GRP78,NIX,and Casp-3),antioxidative-related genes(GST and MRP)and cellular detoxification-related genes(HbⅡB,NOS-1,HO-1,and ENO-1)were upregulated significantly under both acute and chronic thermal stresses.These results demonstrated that the anti-apoptotic system,antioxidant defense system,cellular detoxification system,and heat shock proteins(HSPs)played vital roles for ark shells in response to thermal stress.As acute thermal stress can result in irreversible damage to marine molluscs,it is thus advised that chronic thermal stress should be used to select thermal-resistant ark shell strains.展开更多
Mitochondrial gene(16S rRNA and COI) fragments of Bloody clam Scapharca broughtonii were amplified via PCR, the PCR products were ligated into T vectors, cloned and sequenced. 823 bp and 703 bp nucleotide sequences of...Mitochondrial gene(16S rRNA and COI) fragments of Bloody clam Scapharca broughtonii were amplified via PCR, the PCR products were ligated into T vectors, cloned and sequenced. 823 bp and 703 bp nucleotide sequences of partial 16S rRNA gene and partial COI gene were obtained respectively. The contents of A, T, G and C were 24.79%,23.57%,29.16% and 22.48% in 16S rDNA; 22.05%,33.85%,23.33% and 20.77% in COI. The potential uses of these two sequences were discussed for genetic variation, differentiation and relevant research of different geographic populations in the species.展开更多
文摘半乳糖凝集素(Galectin)作为动物凝集素家族的一员,是一种重要的免疫因子,在脊椎动物和无脊椎动物中都参与了重要的免疫防御反应。为明确魁蚶(Scapharca broughtonii)半乳糖凝集素基因的结构特征、组织分布及其对病原菌刺激的免疫反应规律,本研究从构建的魁蚶转录组文库中筛选得到半乳糖凝集素基因部分序列,通过c DNA末端快速扩增(rapid amplication of c DNA ends,RACE)技术获得该基因c DNA全长序列(命名为Sb Gal)。序列和结构分析表明,该c DNA全长3120bp,编码554个氨基酸,是一个含有4个糖识别结构域(CRD)的且在双壳贝类中较为独特的半乳糖凝集素;预测蛋白的分子量(Mw)为63.3158 k Da,理论等电点(p I)为4.99。同源性及系统分析表明,Sb Gal基因与美洲牡蛎、合浦珠母贝、海湾扇贝galectin的同源性分别为70%、65%、46%,Sb Gal基因四个CRD彼此的相似性为36%—41%。实时荧光定量PCR(q RT-PCR)结果表明:Sb Gal m RNA在魁蚶血细胞、斧足、闭壳肌、外套膜、鳃和肝胰腺中均有表达,血细胞中的表达量最高,在肝胰腺中的表达量最低;注射鳗弧菌后,相对于对照组,Sb Gal基因在所检测的每个组织中m RNA水平上的表达量都显著上调(P<0.01),而且表达量具有显著的时间依赖性和瞬时表达趋势,呈现先升高后降低的趋势。
基金Supported by the National Key R&D Program of China(No.2019YFD0900704)the National Natural Science Foundation of China(No.31972791)the Earmarked Fund for Shandong Modern AgroIndustry Technology Research System(No.SDAIT-14)。
文摘Ocean warming is altering the habitats of marine invertebrates,which has resulted in an increased physiological stress to marine molluscs,especially those intertidal bivalves,such as the ark shell Scapharca broughtonii.We investigated the physiological and transcriptional responses of ark shells to acute and chronic thermal stress results showed that at 33℃,a significantly higher cumulative mortality(55.7%)occurred under acute thermal stress than chronic thermal stress.The apoptosis rate of hemocytes was sustained at higher levels and the necrosis rate was increased significantly in a time-dependent manner under acute thermal stress.However,under chronic thermal stress,the apoptosis and necrosis rates exhibited similar change trends:a rapid increase followed by a gradual decline and sustained at a relatively high level until the end of the experiment.The expressions of heat shock protein genes(HSP20 and HSP90),apoptosis-related genes(TRAF6,GRP78,NIX,and Casp-3),antioxidative-related genes(GST and MRP)and cellular detoxification-related genes(HbⅡB,NOS-1,HO-1,and ENO-1)were upregulated significantly under both acute and chronic thermal stresses.These results demonstrated that the anti-apoptotic system,antioxidant defense system,cellular detoxification system,and heat shock proteins(HSPs)played vital roles for ark shells in response to thermal stress.As acute thermal stress can result in irreversible damage to marine molluscs,it is thus advised that chronic thermal stress should be used to select thermal-resistant ark shell strains.
文摘Mitochondrial gene(16S rRNA and COI) fragments of Bloody clam Scapharca broughtonii were amplified via PCR, the PCR products were ligated into T vectors, cloned and sequenced. 823 bp and 703 bp nucleotide sequences of partial 16S rRNA gene and partial COI gene were obtained respectively. The contents of A, T, G and C were 24.79%,23.57%,29.16% and 22.48% in 16S rDNA; 22.05%,33.85%,23.33% and 20.77% in COI. The potential uses of these two sequences were discussed for genetic variation, differentiation and relevant research of different geographic populations in the species.
