黄颡鱼属两种鱼类的线粒体ND4基因序列变异性分析

以东亚特有种光泽黄颡鱼(Pelteobagrus nitidus)和长须黄颡鱼(Pelteobagrus eupogon)为研究对象,采用PCR技术获得了这两种鱼类的部分线粒体DNA DN4基因及其3′端的tRNA基因碱基共约772个,用MEGA2.1软件分析了此片段序列,采用Kimura双参数模型计算遗传距离,以科属的大鳍(Hemibagrus macropterus)为外类群,用邻接法构建不同水系的光泽黄颡鱼和长须黄颡鱼的分子系统树。不同水系的光泽黄颡鱼的遗传距离在0.000—0.012之间,长须黄颡鱼的遗传距离在0.000—0.003之间,光泽黄颡鱼和长须黄颡鱼种间的遗传距离在0.099—0.108之间,从分子水平上证实了光泽黄颡鱼和长须黄颡鱼为两个有效物种。不同水系的光泽黄颡鱼遗传变异很小,除黑龙江种群外,其他水系的光泽黄颡鱼在分子系统树没有能够按水系区分开来,可能的原因为:(1)不同水系的光泽黄颡鱼之间存在频繁的基因交流;(2)东亚科鱼类的线粒体DNA的进化速率可能较小;(3)人类经济活动可能已影响到光泽黄颡鱼的种群遗传结构。     

黄颡鱼不同组织中同工酶的表达模式

采用聚丙烯酰胺凝胶电泳(PAGE)及特异性组织化学染色技术,研究了黄颡鱼成体眼、心脏、肾脏、肝脏、肌肉及尾鳍等6种组织中的4种同工酶(LDH、MDH、SOD、EST)分化表达模式。结果表明,黄颡鱼的同工酶EST、SOD、MDH具有明显的组织特异性,LDH无明显的组织差异,并对同工酶的组织表达特异性的生理意义进行分析和讨论。     

Isolation and characterization of twelve novel microsatellites in yellow catfish, Pelteobagrus fulvidraco

The yellow catfish Pelteobagrus fulvidraco is a freshwater fish species. Due to overfishing and pollution of freshwater ecosystems, the wild stocks of this fish reduced substantially. We isolated and characterized 12 polymorphic microsatellites of this species. The number of alleles at the 12 microsatellite loci ranged from four to eight, with an average of 6.6/locus. The average observed heterozygosity was 0.72, whereas the expected heterozygosity ranged from 0.60 to 0.86 (average: 0.80). All 12 microsatellites conformed to Hardy–Weinberg Equilibrium and were in linkage equilibrium. These 12 novel microsatellites could facilitate studies of genetic diversity and population structure of the yellow catfish to supply necessary information of conservation of the yellow catfish.     

饥饿胁迫对瓦氏黄颡鱼脂肪代谢的影响

在水温(252)℃条件下, 对初始体重为(23.652.82) g的瓦氏黄颡鱼进行30d饥饿处理, 于饥饿第0、第7、第15和第30天取样, 分析了饥饿胁迫对瓦氏黄颡鱼的生长、体成分、脂肪酸组成和脂肪代谢相关基因表达的影响. 结果表明: 饥饿胁迫显著降低了瓦氏黄颡鱼肥满度、脂体比及肝体指数(p0.05). 肌肉脂肪含量也随着饥饿时间的延长而下降(p0.05). 肝脏中的饱和脂肪酸和肌肉中的单不饱和脂肪酸显著下降, 而肝脏中多不饱和脂肪酸和单不饱和脂肪酸及肌肉中的多不饱和脂肪酸显著上升(p0.05). 此外, 肌肉中的n-6和n-3及肝脏中的n-6多不饱和脂肪酸显著上升, 而肝脏中的n-3多不饱和脂肪酸显著下降(p0.05), 表明瓦氏黄颡鱼饥饿期间主要消耗饱和脂肪酸及单不饱和脂肪酸供能, 保留多不饱和脂肪酸. 饥饿胁迫15-30d, 瓦氏黄颡鱼肝脏脂蛋白酯酶、肝酯酶及肉碱酰基转运酶mRNA表达显著高于对照组(0d)(p0.05), 而脂肪酸结合蛋白及脂肪酸合成酶mRNA的表达显著低于对照组(p0.05), 表明饥饿胁迫可能会促进肝脏脂肪分解供能, 降低脂肪的生物合成.       

Comparative iTRAQ‐Based Quantitative Proteomic Analysis of Pelteobagrus vachelli Liver under Acute Hypoxia: Implications in Metabolic Responses

More and more frequently these days, aquatic ecosystems are being stressed by nutrient enrichment, pollutants, and global warming, leading to a serious depletion in oxygen concentrations. Although a sudden, significant lack of oxygen will result in mortality, fishes can have an acute behavior (e.g., an increase in breathing rate, reduction in swimming frequency) and physiology responses (e.g., increase in oxygen delivery, and reduction in oxygen consumption) to hypoxia, which allows them to maintain normal physical activity. Therefore, in order to shed further light on the molecular mechanisms of hypoxia adaptation in fishes, the authors conduct comparative quantitative proteomics on Pelteobagrus vachelli livers using iTRAQ. The research identifies 511 acute hypoxia‐responsive proteins in P. vachelli. Furthermore, comparison of several of the diverse key pathways studied (e.g., peroxisome pathway, PPAR signaling pathway, lipid metabolism, glycolysis/gluco‐neogenesis, and amino acid metabolism) help to articulate the different mechanisms involved in the hypoxia response of P. vachelli. Data from proteome analysis shows that P. vachelli can have an acute reaction to hypoxia, including detoxification of metabolic by‐products and oxidative stress in light of continued metabolic activity (e.g., peroxisomes), an activation in the capacity of catabolism to get more energy (e.g., lipolysis and amino acid catabolism), a depression in the capacity of biosynthesis to reduce energy consumption (e.g., biosynthesis of amino acids and lipids), and a shift in the aerobic and anaerobic contributions to total metabolism. The observed hypoxia‐related changes in the liver proteome of the fish can help to understand or can be related to the hypoxia‐related response that takes place in similar conditions in the liver or other proteomes of mammals.     

氧化鱼油对黄颡鱼黑色素合成酶及内分泌激素的影响

实验模拟自然氧化条件制备氧化鱼油, 替代普通鱼油加入饲料中, 研究其对黄颡鱼(Pelteobagrus fulvidraco)表皮黑色素、酪氨酸酶活力、血清与脑内分泌激素含量的影响。处理组分别为未替代组(C组)、50%氧化鱼油替代组(Y50组)和100%氧化鱼油替代组(Y100组), 结果表明: 随着氧化鱼油替代普通鱼油的比例提高, 黄颡鱼5级(黑色素占细胞面积80%以上)黑色素细胞比例上升; 酪氨酸酶活力上升, 但各组差异不显著(P>0.05); 皮质酮(CORT)在血清和脑组织中各组含量差异均不显著(P>0.05); 肾上腺皮质激素(ACTH)在脑组织中含量增加 (P<0.05), 而血清中Y50组含量高于C组及Y100组(P<0.05); 血清中促肾上腺皮质激素释放激素(CRH)含量降低, Y50与Y100组之间差异不显著(P>0.05), 而脑组织中各组差异不显著(P>0.05); 血清中α-黑素细胞刺激素(α-MSH)含量, Y100组高于其他组(P<0.05), 而脑组织中各组差异不显著(P>0.05)。上述结果表明, 随着氧化鱼油替代普通鱼油的比例提高, 5级黑色素细胞比例上升, 黄颡鱼血清和脑组织中能互相转换的ACTH与α-MSH总量提高, 变化趋势与表皮黑色素含量和酪氨酸酶活性相一致。     

瓦氏黄颡鱼的繁殖生物学研究

研究了长江中游嘉鱼至新滩口江段瓦氏黄颡鱼的繁殖生物学。性腺发育可分为6个时期。4-7月性成熟系数较高,为繁殖季节。雌、雄鱼的肥满度和脂肪系数在繁殖前和繁殖后各出现1个峰值,繁殖期出现最小值。绝对繁殖力为1088-19765(粒),平均7728±4093(粒);相对繁殖力为23-88(粒),平均55±16(粒)。绝对繁殖力与体长、体重和年龄呈显著的正相关,其中体重与绝对繁殖力的关系最密切。群体性比接近1:1。属一次性产卵类型。两性最小性成熟年龄均为2龄。为补充群体占优势的繁殖群体。     

黄颡鱼仔、稚、幼鱼耗氧率及氨氮排泄率的初步研究

本文测定了不同温度(20、24、28、32℃)下黄颡鱼仔、稚、幼鱼的耗氧率和氨氮排泄率。结果表明,黄颡鱼的耗氧率、氨氮排泄率随体质量增大而降低,随温度升高而增大;体质量、温度与耗氧率和氨氮排泄率的关系可用R_O=0.0224T^0.6428·e^0.1284W、R_N=0.2654T^0.4326·e^0.1417W表示。     

瓦氏黄颡鱼和岩原鲤脾脏的组织学观察

运用组织学方法对瓦氏黄颡鱼和岩原鲤脾脏的显微结构进行了研究.瓦氏黄颡鱼和岩原鲤脾脏被膜薄,仅由一层单层扁平上皮细胞和结缔组织纤维构成,脾小梁明显,红髓和白髓混合,无明显的分界,鞘毛细血管发达;瓦氏黄颡鱼脾小梁细而少,白髓中淋巴细胞密集,在靠近被膜的脾实质边缘区域密集的淋巴细胞形成外形类似淋巴小结的结构,巨噬细胞聚集形成明显的巨噬细胞中心;岩原鲤脾小梁发达,伸入脾实质将脾脏分隔成一个个的小叶,白髓中密集的淋巴细胞较少,未见类似淋巴小结的结构,巨噬细胞分散存在,无明显的巨噬细胞中心.     

嘉陵江大鳍鳠和瓦氏黄颡鱼血液学指标的研究

研究了大鳍鳠和瓦氏黄颡鱼血液学指标的季节变化及种间差异,旨在为探讨三峡工程所引起的环境变化,对两种鱼所产生的生理生态学影响提供基础资料。于2002年9月至2003年6月期间,分春、夏、秋和冬4个季节在嘉陵江水土镇以下江段共采集大鳍鳠111尾,瓦氏黄颡鱼124尾。测定了这两种鱼的红细胞数量、血红蛋白含量、平均红细胞血红蛋白含量、血清葡萄糖浓度、血清甘油三酯浓度和血清总蛋白浓度等6项血液学指标。结果表明,两种鱼的多项血液学指标均存在显著的季节间差异,血液指标的变化趋势并不是随水温的升高而升高。繁殖期两种鱼的血清甘油三酯浓度均显著降低。两种鱼的血清葡萄糖和甘油三酯浓度存在种间差异,瓦氏黄颡鱼的血清葡萄糖和甘油三酯浓度均显著高于大鳍鳠。