饲料牛磺酸对斜带石斑鱼TauT基因表达的影响

发布时间：2018-04-20 22:33

本文选题：斜带石斑鱼 + 牛磺酸转运载体　；参考：《集美大学》2016年硕士论文

【摘要】：石斑鱼(Epinephelus)是一种经济价值很高的暖水性海水鱼类,在我国福建、广东、海南等沿海地区养殖规模很大。石斑鱼牛磺酸合成能力较弱,主要靠外源食物供给来满足其生长发育的需要。牛磺酸转运蛋白(taurine transporter,TauT)是牛磺酸跨膜转运的重要载体,在鱼类的生长、代谢及性成熟过程中发挥着重要作用。本文克隆了斜带石斑鱼TauT基因及饲料中不同牛磺酸水平对斜带石斑鱼(Epinephelus coioides)组织TauT mRNA表达的影响。主要研究结果如下:1、斜带石斑鱼TauT基因克隆首次从斜带石斑鱼肝脏中分离得到TauT基因编码区序列全长,长度为1881bp,编码626个氨基酸,其分子质量为70126.80Da,等电点为7.834。通过对其氨基酸序列分析发现,斜带石斑鱼TauT具有12个跨膜区域,且在第三跨膜区域与第四跨膜区域之间存在这一个亲水基环,这个环含有三个潜在的N-糖基化位点。通过同源性分析和系统发育分析,斜带石斑鱼TauT基因与鲈鱼亲缘关系最近,其次为大西洋鲑,再次为罗非鱼,与其斑马鱼和鲤鱼等其它淡水鱼类亲缘关系较远,而与鸟、哺乳类的亲缘关系则更远。这符合传统分类学意义。2、组织表达分析检测了斜带石斑鱼不同组织的TauT mRNA表达水平。结果发现,TauT mRNA在所有被测组织中都有表达,但在不同组织的表达水平不一致,以肝脏、心脏、脑表达水平最高,肾脏、鳃、脾脏组织的表达次之,以肠道、肌肉、脂肪组织的表达水平为最低。3、饲料牛磺酸对斜带石斑鱼生长的影响本实验配制牛磺酸含量为0(D1)、0.5%(D2)、1%(D3)、1.5%(D4)的4种试验饲料,饲喂斜带石斑鱼84d,并分别于饲喂的第28d、56d、84d称重和采样。结果表明,无论饲喂的第28d、第56d还是第84d,牛磺酸添加组鱼的增重率均显著高于对照组,且1%牛磺酸添加组增重率显著高于其他(p0.05)。随着饲料牛磺酸水平的升高,斜带石斑鱼肝脏、肌肉、肠道牛磺酸含量显著增高(p0.05),且随着养殖d数的增加而增加(p0.05)。4、饲料牛磺酸对斜带石斑鱼TauT mRNA表达的影响在饲喂的第28d时,牛磺酸添加组鱼各个组织的TauT mRNA相对表达量显著高于对照组。D3、D4组的TauT mRNA相对表达量显著高于D1、D2组(p0.05),但D3组的表达量与D4组差异不显著(p0.05)。饲喂的第56d、84d各组TauT相对表达量呈现出与饲喂第28d时一致的结果。同一组织TauT mRNA的相对表达量随着饲喂时间的增加呈现逐渐下降的趋势。
[Abstract]:Epinephelus (Epinephelus) is a kind of warm-water marine fish with high economic value. It is cultivated on a large scale in the coastal areas of Fujian, Guangdong and Hainan in China. The ability of taurine synthesis of grouper is weak, which mainly depends on exogenous food supply to meet the needs of its growth and development. Taurine transporter TauTis is an important carrier of taurine transmembrane transport, which plays an important role in the growth, metabolism and sexual maturation of fish. In this paper, we cloned the TauT gene of Epinephelus coioides and the effect of different taurine levels on the expression of TauT mRNA in the tissues of Epinephelus coioides. The main results are as follows: 1. The TauT gene coding region was cloned from the liver of the oblique grouper for the first time. The length of the coding region was 1881 BP, encoding 626 amino acids, with molecular weight of 70126.80 Daand isoelectric point of 7.834. The amino acid sequence analysis showed that TauT had 12 transmembrane regions, and there was a hydrophilic ring between the third and fourth transmembrane regions, which contained three potential N-glycosylation sites. By homology analysis and phylogenetic analysis, TauT gene was closely related to perch, followed by Atlantic salmon, tilapia and other freshwater fishes such as zebrafish and carp. Mammals are more closely related. This was in accordance with the traditional taxonomic significance. 2. The expression level of TauT mRNA in different tissues of grouper was detected by tissue expression analysis. The results showed that TauT mRNA was expressed in all the tested tissues, but the expression level was different in different tissues. The highest expression level was found in liver, heart and brain, followed by the expression in kidney, Gill, spleen, intestinal tract and muscle. The effect of feed taurine on the growth of the oblique grouper was the lowest in adipose tissue. The experiment was conducted to prepare four experimental diets with taurine content of 0 D _ (1) and 0.5 ~ (0.5) D _ (2) and D _ (3) and 1.5 ~ (5) D _ (4). The four experimental diets were fed to the oblique grouper for 84 days and were weighed and sampled on the 28th day, 56d ~ (84) d, respectively. The results showed that the weight gain rate of taurine added group was significantly higher than that of control group on the 28th day, 56th day and 84th day, and the weight gain rate of 1% taurine group was significantly higher than that of other groups. The content of taurine in liver, muscle and intestine increased significantly with the increase of feed taurine level, and increased with the increase of the number of cultured days. The effect of feed taurine on the expression of TauT mRNA in oblique grouper was 28 days after feeding. The relative expression of TauT mRNA in all tissues of taurine group was significantly higher than that in control group. D3 group was significantly higher than that in D1 D 2 group (P 0.05), but the expression of TauT mRNA in D3 group was not significantly different from that in D 4 group (P 0.05). The relative expression of TauT in each group on the 56th day after feeding showed the same result as that on the 28th day. The relative expression of TauT mRNA in the same tissue decreased with the increase of feeding time.
【学位授予单位】：集美大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S917.4

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