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1.
硬酯酰辅酶A脱氢酶(Stearoyl-CoA Desaturase,SCD)是参与脂肪酸脱氢反应的限速酶和关键酶,此酶编码基因SCD对增加膜磷脂的不饱和脂肪酸成分,提高细胞膜在低温下的流动性发挥重要作用,可能是抗寒过程中的关键基因成员。本研究采用cDNA末端快速扩增技术(Rapid Amplifications of cDNAEnds,RACE)克隆了鲤(Cyprinus carpio)脑组织CcSCD基因的全长cDNA序列,采用实时荧光定量PCR技术检测该基因在低温(6℃)和常温(23℃)条件下的转录表达差异,对其蛋白编码序列的结构和功能进行了预测分析。结果显示,CcSCD基因cDNA全长2618bp,包含一个由324个氨基酸残基组成的长度为975bp的阅读框(ORF);蛋白分子进化树显示鲤的SCD和草鱼(Ctenopharyngodon idella)的SCD蛋白同源性最高,相似性达88%;实时荧光定量结果表明,低温刺激下(6℃),CcSCD基因表达水平是常温条件下(23℃)的13.9倍,差异非常显著(P0.01)。本研究旨在为今后构建表达载体,通过遗传操作等研究手段鉴定其抗寒功能奠定基础。  相似文献   

2.
Physiological responses of milkfish (Chanos chanos) under cold shock and acclimation were investigated. The experimental milkfish, a warm-water teleost, were initially acclimated at 25 °C and then transferred directly to 15 °C; stress responses of this species were monitored for 1 week. Parameters monitored included plasma glucose, lactate, and lipids, as well as stearoyl-CoA desaturase activity and fatty acid compositions of hepatic membranes. All parameters showed significant changes in the process of cold acclimation. A hyperglycemic response indicated by a notable and steady increase in plasma glucose levels from 85 mg dl−1 to the highest level of 458.2 mg dl−1 in 24 h was followed by a rapid decline thereafter. The elevation in plasma glucose content under cold shock resulted from gluconeogenesis and glycogenolysis, indicated by correlated changes in plasma glucose with fructose-1,6-biphosphatase and phosphorylase a activities. Plasma lactate concentrations remarkably increased from 47 mg dl−1 on day 0 to 149.6 and 120.4 mg dl−1 on days 1 and 2, respectively, and then rapidly declined to the same level as the control thereafter. In contrast, plasma lipids increased gradually from 44.8 mg dl−1 to 191 mg dl−1 over the 5-day acclimation period, followed by a declining trend from day 6 on. Furthermore, changes in monounsaturated fatty acids were highly correlated with those of stearoyl-CoA desaturase activities in hepatic microsomes of milkfish during cold acclimation. Results indicate that in milkfish subjected to cold stress, plasma hyperglycemic and hyperlactemic responses can be used as acute stress indicators, and plasma lipids can be used as a chronic stress indicator.  相似文献   

3.
种青养鱼模式下的草鱼肌肉营养成分和品质特性   总被引:5,自引:2,他引:3  
为探究种青养鱼养殖模式对草鱼肌肉营养成分和品质特性的影响,随机选取以种青喂草为主养殖模式下养殖的草鱼(生态草鱼)和投喂人工配合饲料进行养殖的草鱼(饲料草鱼)各16尾,测定其肌肉系水力和质构特性指标,以及肌肉常规营养成分、矿物元素、氨基酸和脂肪酸含量。结果显示,生态草鱼和饲料草鱼肝体比和空壳率无显著性差异;生态草鱼肌肉系水力指标中滴水损失显著低于饲料草鱼,冷冻渗出率不显著地低于饲料草鱼,失水率不显著地高于饲料草鱼,p H值无显著性差异;肌肉的硬度、弹性、凝聚性、胶黏性和回复性均无显著性差异;生态草鱼粗脂肪含量显著低于饲料草鱼,水分、灰分、粗蛋白含量均无显著性差异;生态草鱼P和Fe含量均显著高于饲料草鱼,Mg、Mn和Cr含量均极显著高于饲料草鱼;生态草鱼和饲料草鱼肌肉氨基酸组成基本一致,均含有17种氨基酸,其中人体必需氨基酸总量分别为6.85%和6.27%。生态草鱼必需氨基酸指数(EAAI)为76.07,而饲料草鱼为77.29,饲料草鱼略高于生态草鱼。生态草鱼和饲料草鱼肌肉均含19种脂肪酸,其中棕榈酸、花生四烯酸(ARA)、亚油酸(LA)、油酸、二十二碳六烯酸(DHA)和硬脂酸含量较高,为主要脂肪酸,而花生五烯酸(EPA)+DHA含量分别为8.95%和10.70%,且差异显著。研究表明,生态草鱼和饲料草鱼在肌肉质构特性方面无显著性差异,与饲料草鱼相比,生态草鱼具有肌肉系水力强、低脂肪和矿物元素含量高的特点。  相似文献   

4.
ghrelin是一种在脊椎动物摄食调节过程中起重要作用的脑肠肽,具有明显的摄食促进作用。实验利用同源克隆技术获得了草鱼ghrelin基因的cDNA序列和DNA序列,其中cDNA序列全长506 bp,包括90 bp的5′端非编码区(5′-untranslated region,5′UTR),312 bp的开放阅读框(open reading frame,ORF),以及104 bp的3′端非编码区(3′-untranslated region,3′UTR)。开放阅读框编码的103个氨基酸的ghrelin前体肽,经剪切加工后形成含有19个氨基酸的成熟肽。氨基酸序列分析结果显示,草鱼ghrelin与硬骨鱼类ghrelin相似度最高,而与其他脊椎动物相似度较低,同时草鱼ghrelin成熟肽N端的"活性中心"(active core)为鲤科鱼类中常见的GTSF形式。与大多数硬骨鱼类的ghrelin基因结构相同,草鱼ghrelin基因也包括4个外显子和3个内含子。荧光定量PCR检测到ghrelin mRNA大量分布于草鱼的前肠和脾,脑、肾、肝、肌肉、皮和鳔等组织也有ghrelin mRNA分布。草鱼脑和肠中的ghrelin表达水平在摄食后下降,随着饥饿时间的延长表达水平逐步升高,最后维持在较高水平,表明ghrelin作为摄食启动信号对草鱼的摄食活动起到了促进作用。  相似文献   

5.
为比较山泉流水和池塘养殖草鱼的品质区别,测定了体质量为1500~1750 g的两种方式养殖草鱼的基本营养、矿物元素、胶原蛋白、氨基酸和脂肪酸含量及肌肉抗氧化能力。测定结果表明,山泉流水养殖草鱼水分、粗脂肪、K和Na含量显著低于池塘养殖草鱼(P<0.05),粗蛋白、灰分、P、Ca、Mg、Cu、Zn、Fe、Mn和Se含量显著高于池塘养殖草鱼(P<0.05);山泉流水养殖草鱼肌肉不可溶性胶原蛋白含量和超氧化物歧化酶活力显著高于池塘养殖草鱼(P<0.05),丙二醛含量则显著低于池塘养殖草鱼(P<0.05);山泉流水养殖草鱼的总必需氨基酸、鲜味氨基酸分别为15.76%、5.60%,显著高于池塘养殖草鱼(P<0.05),氨基酸评分、化学评分和必需氨基酸指数均高于池塘养殖草鱼;山泉流水养殖草鱼饱和脂肪酸、单不饱和脂肪酸显著低于池塘养殖草鱼(P<0.05),多不饱和脂肪酸含量显著高于池塘养殖草鱼(P<0.05)。综上可知,山泉流水养殖草鱼在蛋白与脂肪含量、肌肉抗氧化能力、氨基酸平衡性及脂肪酸质量等方面优于普通池塘养殖草鱼。  相似文献   

6.
草鱼的两种新型免疫球蛋白基因IgZ-2和IgM-IgZ   总被引:2,自引:2,他引:0  
肖凡书  许巧情  王欣欣  聂品 《水产学报》2010,34(12):1891-1900
在草鱼中新发现的两种免疫球蛋白重链的cDNA和基因组序列,其中的一种IgZ命名为IgZ-2,以区别于已报道的IgZ,另一种只有两个恒定区,一个恒定区与IgM相似而另一个与IgZ相似,这一特征与已报道的鲤的IgM-IgZ相似,故同样称为IgM-IgZ。分泌型IgZ-2的cDNA序列包含1889bp,编码539个氨基酸,其3'编码区包含267bp,但缺乏5'非编码区及部分可变区序列。分泌型IgM-IgZ的cDNA全长为1316bp,编码361个氨基酸,其5'非编码区包含3bp,3'非编码区包含227bp。膜结合型IgM-IgZ由两个膜外显子与CH2中的一个剪切位点剪切而成。氨基酸序列比对结果显示IgZ-2和IgM-IgZ的恒定区存在保守的半胱氨酸。系统进化树分析显示,草鱼IgZ-2以较高的支持率与斑马鱼IgZ聚为一枝,再与草鱼IgZ、草鱼IgM-IgZ和鲤IgM-IgZ这一枝聚为一类。用半定量RT-PCR检测IgZ-2和IgM-IgZ在4条草鱼的器官/组织中的表达,发现分泌型IgZ-2、分泌型IgM-IgZ和膜结合型IgM-IgZ在4条鱼中的表达存在个体差异,但主要都在免疫器官中表达。  相似文献   

7.
本研究在前期已获得的黄颡鱼Pelteobagrus fulvidraco转录组基础上,利用BLAST程序从中筛选获得黄颡鱼c Gn RH基因的候选序列,再通过氨基酸序列分析从中筛选获得c Gn RH的全长c DNA为261bp,编码86个氨基酸,其核心十肽的序列为QHWSHGWYPG,相对分子质量为9 755.5、理论PI值为9.02。序列同源比对发现:黄颡鱼与斑马鱼Danio rerio、草鱼Ctenopharyngodon idella、鲤Cyprinus carpio中c Gn RH氨基酸的相似性分别高达70.93%、68.60%和67.44%。用MEGA构建的黄颡鱼与其他27种硬骨鱼c Gn RH的Neighbour-joining进化树发现,黄颡鱼c Gn RH先与脂鲤科的墨西哥丽脂鲤Astyanax mexican共聚类,再依次与鲤科的斑马鱼、草鱼、黑头呆鱼Pimephales promelas、稀有鮈鲫Gobiocypris rarus等鱼的c Gn RH序列聚类。本研究首次筛选获得黄颡鱼的c Gn RH序列,并利用生物信息学软件进行鉴定分析,为后续的基因表达和c Gn RH调节生长生殖作用的研究提供序列资源及基础。  相似文献   

8.
作为重要的转运载体,SGLTs(钠依赖性葡萄糖协同转运蛋白,sodium-glucose cotransporters)在物质的吸收过程中发挥着关键的作用。SGLT1和SGLT2作为SGLTs家族的重要成员,参与调节体内的葡萄糖吸收,从而维持血糖的稳态。为研究SGLT1和SGLT2在草鱼葡萄糖吸收过程中的作用,本实验利用RT-PCR技术从草鱼前肠和肾脏中分别克隆了基因sglt1和sglt2,对其进行生物信息学分析,并利用荧光定量PCR技术检测其mRNA的表达。结果显示,草鱼sglt1和sglt2的开放阅读框(open reading frame,ORF)分别为1 977和1 989 bp,并分别编码658和662个氨基酸。经过预测,草鱼SGLT1和SGLT2蛋白均为14次跨膜结构。氨基酸序列比对及系统进化树分析结果显示,草鱼sglt1和sglt2与金鱼、金线鲃中sglt1和sglt2的亲缘关系最近。荧光定量PCR结果显示,sglt1在草鱼肠道和肾脏组织中表达量较高,在其他组织中表达量较低;sglt2在草鱼肾脏组织中表达量最高,在其他组织中表达量较低。葡萄糖灌喂实验结果显示,草鱼前肠中sglt1和肾脏中sglt2的表达量在灌喂1 h后显著增加。在离体实验中,葡萄糖处理CIK细胞能够显著增加sglt1和sglt2的表达量。本研究为完善SGLTs在调控鱼类血糖稳态方面具有的功能提供了理论依据。  相似文献   

9.
10.
An expressed sequence tag of grass carp leukocyte cell–derived chemotaxin 2 (LECT2) gene was screened from an established intestinal cDNA library. Rapid amplification of cDNA ends gave rise to a full-length LECT2 cDNA (gcLECT2) with a complete open-reading frame of 474 bp, encoding 158 amino acids about 17.9 kDa. Homology search and sequence alignment showed that this deduced protein sequence shared a high identity with LECT2 from other vertebrates. Western blotting indicated immunological cross-reactivity occurs between grass carp and human LECT2 protein. This gcLECT2 genomic sequence is 1,868 bp in size, which consists of five exons and four introns. Real-time quantitative PCR analysis revealed that gcLECT2 gene is ubiquitously expressed in different tissues of healthy grass carp including brain, gut, liver, spleen, kidney, muscle and heart, while the expression levels were significantly increased in liver and spleen followed by Aeromonas salmonicida infection. 992 bp 5′-flanking region sequence was cloned and analyzed, where one CAAT box and one GC island were found. Our results showed that the LECT2 is suggested to be most possibly involved in the grass carp’s immune response.  相似文献   

11.
草鱼SREBP-1基因的克隆及糖对其在肝脏中表达的影响   总被引:1,自引:1,他引:0  
固醇调节元件结合蛋白(SREBPs)是调控糖脂代谢相关基因表达的关键核转录因子。为获知草鱼SREBP-1基因的序列及其在肝脏中的表达规律,本实验采用同源克隆和RACE方法获得了草鱼SREBP-1基因的部分cDNA序列,并通过生物信息学方法对该基因及所编码蛋白的结构特征进行了分析;采用实时荧光定量PCR技术,对SREBP-1基因在8种不同组织的表达规律及低糖(糖含量24%)和高糖(糖含量42%)投喂条件下肝脏中的表达水平进行了研究。结果显示,所克隆到的草鱼SREBP-1基因cDNA长4 760 bp,其中包括开放读码框3 426bp,编码1 141个氨基酸;草鱼SREBP-1具有一个典型的碱性螺旋-环-螺旋亮氨酸拉链结构(bHLH-zip);氨基酸序列比对结果显示,草鱼SREBP-1与其他鱼类的同源性在76%~88%之间,与斑马鱼的进化关系最近;草鱼SREBP-1基因在脑中的表达量最高,肝脏和肠次之,在肾脏、脾脏、肌肉、脂肪和性腺中均有少量表达;与对照组相比,SREBP-1基因在高糖诱导下表达量显著提高(P0.05),低糖诱导下没有显著性差异。研究表明,在高糖负荷条件下,草鱼肝脏中SREBP-1可能会促进糖的利用和转化,从而参与糖代谢调节过程,为丰富鱼类糖代谢调控机理提供研究资料,并有望为提高鱼类对饲料糖的利用效率提供理论依据。  相似文献   

12.
脂肪酸合成酶(FASN)是动物体内脂肪酸合成的关键酶。本研究利用逆转录PCR和RACE技术获得鲤Cyprinus carpio FASN全长cDNA序列为8 927bp,开放阅读框7 533bp,编码2 511个氨基酸。FASN蛋白质相对分子量274 145.67D,理论等电点(PI)为6.10。氨基酸同源性分析结果显示:鲤FASN基因与其他鱼类同源性为75.13%~95.34%,与人同源性为61.81%。系统进化树结果显示:鲤FASN氨基酸序列与金线鲃Sinocyclocheilus grahamia聚为一支,同源性最高。实时荧光定量PCR(RT-qPCR)检测结果表明:FASN基因鲤脑组织中表达量最高,肝脏次之,血液中最低。鲤FASN基因的获得为进一步深入研究鲤脂肪酸的合成途径及脂肪发育分子调控机制奠定了基础。  相似文献   

13.
We aimed to investigate proximate and fatty acid composition of important freshwater fish species in the Czech Republic. Sampled fish include seven species from intensive farming: African catfish, rainbow trout, Wels catfish, Nile tilapia, brook trout, northern whitefish, and pikeperch; eight species from semi-intensive culture systems: common carp, northern pike, pikeperch, grass carp, European perch, tench, silver carp, and catfish; and three species from extensive culture systems: rainbow trout, tench, and common carp. The fat content and fatty acid composition were highly influenced by the culture systems. Simultaneously, we observed a significant dependence of fatty acid composition on the fat content. The content of saturated fatty acids was below 34% in all analyzed fish. Northern pike, pikeperch, and European perch contained with over 50% the highest proportion of polyunsaturated fatty acids. Intensively cultured fish reached the highest content of eicosapentaenoic and docosahexaenoic fatty acid. Nutritional quality was determined by atherogenic and thrombogenic indexes which ranged from 0.27 to 0.63 and 0.20 to 0.61 and by ratios n-3/n-6 (0.54–3.45) and polyunsaturated/saturated fatty acids (0.67–2.01). Results demonstrated that the flesh of all studied species are of high nutritional quality.  相似文献   

14.
草鱼胰岛素样生长因子_基因克隆及序列分析   总被引:3,自引:1,他引:3  
采用逆转录-聚合酶链式反应(RT-PCR)方法,从草鱼肝脏的总RNA中扩增出胰岛素样生长因子-I(IGF-I)基因序列,定向克隆至质粒pUC18,测宇了该基因序列,推导期编码的蛋白序列,克隆的cDNA序列编码包括B,C,A,D和E五个区域的17个氨基酸,与鲤IGF-I成熟肽比较,核酸序列和氨基酸序列的同源性分别为93.8%和97.1%,E区域分析结果表明,所克隆的草鱼IGF-I序列属于IGF-IEa-2亚型。  相似文献   

15.
Temporal changes in physiological parameters and enzyme activities related to carbohydrate metabolism in the milkfish (Chanos chanos) and the grass carp (Ctenopharyngodon idella) under cold shock at 15 °C were examined in order to better understand thermal compensation mechanisms of teleosts with different cold tolerances. The plasma glucose, lactate, and lipid contents as well as enzyme activities of citrate synthase, glucose-6-phosphate dehydrogenase, fructose-1,6-bisphosphatase, phosphorylase a, and lactate dehydrogenase at varying time intervals were monitored. The results show that changes in plasma glucose and lipid contents of the milkfish were more notable than those of the grass carp, but the elevation in plasma lactate contents in the grass carp occurred earlier and was much greater than that in the milkfish. Furthermore, changes in plasma glucose contents in the milkfish were correlated with the enzyme activities of phosphorylase a and fructose-1,6-bisphosphatase, but in the grass carp they were correlated with glucose-6-phosphate dehydrogenase and lactate dehydrogenase activities instead. In addition, the change in lactate dehydrogenase activity in the grass carp was more notable than those of other enzymes, but lactate dehydrogenase activities in the milkfish steadily decreased during cold compensation. The results demonstrate that the two species (milkfish and grass carp) respond quite differently to cold shock, and this may be related to their differences in cold tolerance.  相似文献   

16.
草鱼胞质苹果酸脱氢酶(cMDH)的序列克隆及分析   总被引:1,自引:0,他引:1  
以实验室构建的草鱼(Ctenopharyngodon idellus)肠道cDNA文库苹果酸脱氢酶(cMDH)EST序列为基础,采用末端快速扩增法(RACE),从健康雌性草鱼(Ctenopharyngodon idellus)肠道细胞RNA中获得1391 bp的草鱼肠道cMDH的cDNA序列(NCBI登录号:EU569765)。结果显示:该序列包含62 bp的5′非编码区(5′-UTR),330 bp的3′非编码区(3′-UTR),典型加尾信号AATAA位于polyA起点上游16 bp。开放阅读框ORF长999 bp,共编码333个氨基酸,预测蛋白等电点为6.67,大小为36 kDa。多序列比对显示草鱼胞质苹果酸脱氢酶具有典型的苹果酸脱氢酶功能区保守序列,该酶与斑马鱼cMDH相似度最高达到95.5%,与模式植物拟兰介的相似度为57.8%,其预测三级结构具有典型cMDH功能区。Southern杂交结果表明草鱼cMDH属于多拷贝基因家族。  相似文献   

17.
采用RT-PCR和RACE技术,克隆了奥利亚罗非鱼β雌激素受体基因(estrogen receptorβ,ERβ)两种亚型的cDNA全序列(ERβ1和ERβ2)。荧光定量PCR分析雌雄奥利亚罗非鱼两种亚型的组织分布,并观察注射外源雌激素对雄性奥利亚罗非鱼下丘脑-垂体-性腺轴雌激素受体ERα和β(β1/β2)基因表达的影响。序列分析表明,ERβ1cDNA全长为4262bp,其中包含239bp5′非编码区,2349bp3′非编码区和1674bp的开放阅读框,共编码557个氨基酸。ERβ2 cDNA全长为2506bp,包含5′非编码区393bp,3′非编码区109bp,阅读框为2004bp,共编码667个氨基酸。氨基酸序列同源性分析显示奥利亚罗非鱼ERβ1与尼罗罗非鱼的相似性高达99.1%,而与鲈形目其它鱼类的相似性为82.6%~94.2%。ERβ2氨基酸序列与尼罗罗非鱼的相似性为98.7%,与大口黑鲈、虹鳟、底鳉及斑马鱼的相似性分别为81.8%、76.3%、64.7%和55.0%。在系统进化树上奥利亚罗非鱼的ERβ1和ERβ2分别与尼罗罗非鱼的相应受体聚类。奥利亚罗非鱼ERβ1/β2基因在所检测的10种组织中均有...  相似文献   

18.
根据鲤热休克蛋白70(Heat shock protein,HSP70)序列(AY120894)设计并合成一对引物,以草鱼(Cteno-pharyngodon idella)肝胰脏组织总RNA为模板,RT-PCR扩增获得草鱼HSP70基因cDNA部分序列,并进行了组织表达差异性研究。结果显示:所获为序列为480 bp,获得GeneBank登陆号为FJ483832。序列测序结果显示,HSP70扩增序列与鲤、斑马鱼、鲋的同源性为:93%、91%、93%。另外,所获序列HSP70在草鱼脂肪、肌肉、肠、脑、粘液、性腺、鳔、肝胰脏、心脏、脾脏、鳃、鳍12个组织的表达存在差异,HSP70在草鱼这12个组织中均检测到表达,其中在鳍中表达最高,极显著高于其他组织(P<0.01);在鳔中表达次之,且与脑、心脏、性腺中表达差异不显著;在粘液中表达最低。  相似文献   

19.
Follicle-stimulating hormone beta subunit (FSHβ) and luteinizing hormone beta subunit (LHβ) have been cloned and characterized from the pituitary of grass carp (Ctenopharyngodon idella). The full length of FSHβ and LHβ cDNA was 393 bp and 441 bp, with open reading frame encoding proteins of 130 and 146 amino acids, respectively. Phylogenetic analysis of the proteins of FSHβ and LHβ showed a high homology with other fishes. Homology analysis also indicated that LHβ has higher conservation than FSHβ. The expression analysis of grass carp FSHβ and LHβ by RT-PCR suggested that they were only expressed in the pituitary. Real-time quantitative PCR protocols were developed and validated to measure FSHβ and LHβ mRNAs during ovarian development. The FSHβ and LHβ mRNA level was very low in the pituitaries of early-pubertal fish and significantly increased during the ovulation period. These results suggested that in grass carp the gonadotropins synthesized synchronously in order for asynchronous oogenesis to take place.  相似文献   

20.
草鱼HSP90基因cDNA序列克隆及其组织表达差异   总被引:1,自引:0,他引:1  
根据斑马鱼HSP90(Heat shock protein)序列(NM_131328)设计并合成一对引物,提取草鱼肝脏组织总RNA,RT-PCR扩增获得草鱼HSP90基因cDNA部分序列596 bp,获得GenBank登陆号为FJ517554.将测序结果利用DNAman软件与其他几种已知序列的鱼进行比对,结果表明,草鱼HSP90与斑马鱼、鲤、鲋的同源性依次为90%、89%、92%.同时利用半定量(Semi-quantitative,SQ)RT-PCR技术检测HSP90在草鱼脂肪、肌肉、肠、脑、粘液、性腺、鳔、肝脏、心脏、脾脏、鳃、鳍12个组织的表达差异.结果表明,HSP90在草鱼除了鳍外的其他11个组织中均检测到表达,其中在心脏中表达最高,但与鳃、性腺、脑、脾脏中的表达无显著差异(P>0.05),在脂肪、粘液、鳔组织中的表达显著低于其他几种组织(P<0.05),在肝脏、肌肉与肠中的表达无显著差异(P>0.05).  相似文献   

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