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1.
V. N. Williams B. J. Reading N. Hiramatsu H. Amano N. Glassbrook A. Hara C. V. Sullivan 《Fish physiology and biochemistry》2014,40(2):395-415
The multiple vitellogenin (Vtg) system of striped bass, a perciform species spawning nearly neutrally buoyant eggs in freshwater, was investigated. Vitellogenin cDNA cloning, Western blotting of yolk proteins (YPs) using Vtg and YP type-specific antisera, and tandem mass spectrometry (MS/MS) of the YPs revealed the complex mechanisms of yolk formation and maturation in this species. It was discovered that striped bass possesses a tripartite Vtg system (VtgAa, VtgAb, and VtgC) in which all three forms of Vtg make a substantial contribution to the yolk. The production of Vtg-derived YPs is generally similar to that described for other perciforms. However, novel amino-terminal labeling of oocyte YPs prior to MS/MS identified multiple alternative sites for cleavage of these proteins from their parent Vtg, revealing a YP mixture far more complex than reported previously. This approach also revealed that the major YP product of each form of striped bass Vtg, lipovitellin heavy chain (LvH), undergoes limited degradation to smaller polypeptides during oocyte maturation, unlike the case in marine fishes spawning buoyant eggs in which LvHAa undergoes extensive proteolysis to osmotically active free amino acids. These differences likely reflect the lesser need for hydration of pelagic eggs spawned in freshwater. The detailed characterization of Vtgs and their proteolytic fate(s) during oocyte growth and maturation establishes striped bass as a freshwater model for investigating teleost multiple Vtg systems. 相似文献
2.
采用同源克隆和末端快速扩增（RACE）方法,从半滑舌鳎脑垂体中克隆了促性腺激素α亚基（CGα）全长cDNA（GenBank序列登录号：JQ364953）.半滑舌鳎CGα基因全长685bp,其开放阅读框384bp,编码含127个氨基酸的蛋白,N端33个氨基酸为信号肽.半滑舌鳎CGα成熟肽与其他脊椎动物CGα成熟肽结构特征相似,具有10个半胱氨酸残基和两个N-糖基化位点.CGα成熟肽序列分析表明,半滑舌鳎CGα与鲽形目和鲈形目鱼类CGα同源性为60％～70％,与鲤形目鱼类CGα同源性为55％～60％.实时荧光定量RT-PCR结果表明,半滑舌鳎CGα mRNA在被检测的12个组织中均有表达,除头肾和脾脏、脾脏和肝脏间表达量差异不显著外,其他组织间表达量差异显著（P＜0.05）;CGα mRNA在垂体组织中大量表达,其次是鳃、肾脏、肌肉、卵巢和脑组织,而在心脏、头肾、肝和脾等组织中表达量很低.本研究为进一步探讨促性腺激素在半滑舌鳎繁殖生理中的作用机制奠定基础. 相似文献
3.
以海带(Laminaria japonica)为原料,采用阴离子交换和自由基氧化降解反应制备了不同分子量和硫酸根含量的岩藻聚糖硫酸酯,然后以血浆复钙时间(RT)、活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)为指标,研究海带岩藻聚糖硫酸酯抗凝血活性的构效关系.结果表明,采用离子交换,可从海带糖提取物中分离出低硫大分子组分F-A和高硫大分子组分F-B.粗糖经自由基氧化降解,可得到分子量为1.5 kD和8.0 kD左右的低分子组分,实验重复性好,产物分子量集中,其中分子量8.0 kD左右的低分子组分硫酸根含量最高.抗凝血实验表明,岩藻聚糖硫酸酯能显著延长RT、APTT和TT,尤以高硫组分大分子F-B抗凝血效果最好,而对PT影响不大,说明岩藻聚糖硫酸酯对外源凝血系统影响很小,它的抗凝血活性主要是通过内源性凝血途径来实现的.岩藻聚糖硫酸酯分子量对抗凝血活性的影响要比硫酸根含量的影响更大,其抗凝血活性随着分子量的降低而显著降低.对于分子量相近的岩藻聚糖硫酸脂,硫酸根含量越高,则抗凝血活性越高.总之,岩藻聚糖硫酸酯分子量和硫酸根含量越高,其抗凝活性越高. 相似文献
4.
中国南方地区罗非鱼无乳链球菌的分子流行病学研究 总被引：8，自引：5，他引：3
从广东省以及海南省等地区养殖的患病罗非鱼体内分离、收集到多株致病菌,经生化分析和分子生物学鉴定,均为无乳链球菌。对这些菌株分别进行了耐药谱测定、分子分型试验以及分子血清型分析。药敏试验结果表明,2007—2010年分离到的无乳链球菌耐药谱基本相似;多位点可变数目串联重复序列分析(MLVA)试验中,选择5个高变异指数的可变数目重复位点(VNTR)进行分子分型,结果表明,所有鱼源无乳链球菌菌株为同一MLVA型,而作为对照的牛源无乳链球菌则明显不同;为了对这些菌株进一步分型,分别进行了分子血清型和表面蛋白抗原基因的检测,结果表明,鱼源无乳链球菌的分子血清型均为Ⅰa型,表面蛋白抗原均为alpha-C蛋白。这进一步说明了不同年份和不同地区的鱼源无乳链球菌在基因水平上为同一分子类型,具有相同的起源或传染源。同时也说明,我国南方地区罗非鱼无乳链球菌在这几年中未发生明显的遗传变异。这些结果为罗非鱼无乳链球菌病疫苗研制,疫病监测及药物防治的研究提供理论依据。 相似文献
5.
为了研究珠母贝属的分类地位和系统演化情况,通过聚合酶链式反应技术(PCR)扩增并直接测序出雷州半岛珠母贝属中的马氏珠母贝、大珠母贝、珠母贝、斑珠母贝和黑珠母贝的3种线粒体基因(12S r RNA、16S r RNA和COⅠ)部分序列,分析其碱基组成和种间遗传距离。同时结合Gen Bank上发表的白珠母贝序列,构建珠母贝属的分子系统树。结果显示,5种珍珠贝的3种基因部分序列碱基AT含量大于GC含量,与其他无脊椎动物线粒体DNA序列基本一致,序列都处于高度饱和的状态。系统分析显示,构建的分子系统树与传统的形态分类基本一致。在黑珠母贝和白珠母贝亲缘关系上,3种线粒体DNA片段在碱基组成、种间遗传距离和系统进化树上都显示黑珠母贝和白珠母贝非常相近,可以认为是同一种中的2个亚种。在斑珠母贝的亲缘关系上,系统分析显示斑珠母贝与黑珠母贝和白珠母贝更为接近。研究表明,大珠母贝和珠母贝在系统进化中较早的分离出来,是一个比较原始的种类。3种分子标记对马氏珠母贝亲缘关系分析上存在一定差异,根据现有的数据尚不足以得出结论,需进一步做分子系统研究并结合形态特征和解剖结构进行分析。 相似文献
6.
3个地理群体仿刺参D-loop序列的变异及系统发生分析 总被引：3，自引：3，他引：0
为研究中国大连(CD)、朝鲜罗津(KN)和俄罗斯海参崴(RV)3个仿刺参群体的遗传结构,实验采用PCR扩增和测序技术,对3个群体共计71头仿刺参的线粒体D-loop序列进行了分析。结果显示,D-loop序列长度为447~465 bp,平均A+T含量(59.2%)显著高于G+C含量;共检测到119个变异位点,多态位点比例为24.24%,其中简约信息位点为53个,共有40种基因型,群体共享基因型7个。遗传多样性参数分析显示,3个群体均显示出较丰富的遗传多样性;分子方差(AMOVA)分析表明,3个群体间遗传分化较弱或只有中度分化,且93.04%的变异来自群体内。CD群体与RV群体之间遗传距离最远,为0.042,KN群体与RV群体之间遗传距离最近,为0.037 4。将本研究所得序列结合GenBank中青岛(QD)和威海(WH)仿刺参的D-loop序列构建系统发育树,QD与WH仿刺参首先聚为一小支,然后与CD群体聚为一大支,KN群体与RV群体聚为独立一支,这一聚类方式符合地理隔离模式。 相似文献
7.
分别用热酸抽提法、碱抽提法和胃蛋白酶消化法分离豚链球菌NUF849的类M蛋白,通过SDS-PAGE和Western-blotting印迹法分析比较三种方法所提类M蛋白的组成和抗原性差异。结果表明,热酸抽提法分离制备的类M蛋白得率和纯度都较其它两种方法高,蛋白的抗原性保持较好。采用热酸提取法提取5株豚链球菌NUF633、NUF693、 NUF701、 NUF812、 NUF849和2株停乳链球菌SD、L2的类M蛋白,其SDS-PAGE图谱明显不同,种间差异明显, 豚链球菌主要类M蛋白的分子量分别为60、48、37、30、27、24和15kDa,停乳链球菌主要类M蛋白的分子量分别为68、48、42、37、29、26、23、21、19、17、15、14和11kDa。Western-blotting结果显示,兔抗豚链球菌血清可与豚链球菌的两条类M蛋白带结合,分子量分别为60和37kDa;与停乳链球菌的两条类M蛋白带结合,分子量为68和37 kDa。两种链球菌主要类M蛋白组成及其抗原性差异明显。 相似文献
8.
In this study, three molecular markers including random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) were used to evaluate genetic variation of green tiger prawn Penaeus semisulcatus collected from two geographically isolated environments; located in the Manifa, Arabian Gulf, Saudi Arabia and Ataka, Suez Gulf, Egypt. Genetic parameters included the percentage of polymorphism (P%), effective alleles (Ne), Nei genetic diversity (H) and Shannon index (I), which were calculated based on molecular data. All three marker systems distinguished genetic variation of P. semisulcatus in various levels. The highest polymorphism (91.30%) was obtained with SSR, followed by ISSR (82.26%) and RAPD markers (62.04%), respectively. Our results indicate that SSR appeared to be the best suited molecular assay for assessing the genetic variation between genotypes of P. semisulcatus. The present study indicated that Manifa and Ataka genotypes were closely related. Moreover, the analysis of variability could require more than one DNA‐based molecular marker techniques. 相似文献
9.
为分离日本鳗鲡脾脏中的抗菌肽,实验采用10 ku和3 ku切向流中空纤维柱对脾脏醋酸粗提物进行分级分离,并结合阳离子交换层析和反相高效液相层析技术对小于10 ku和小于3 ku 2部分样品分别进行分离纯化。结果显示,2种分子量截留纤维柱超滤获得了大于10 ku、小于10 ku和小于3 ku 3部分样品。小于10 ku和小于3 ku蛋白样品抗菌活性较大于10 ku样品强。对小于10 ku样品经阳离子交换层析以及采用pH 9缓冲液进行反相高效液相层析分离纯化,获得一个抗菌肽,质谱分析其分子量为1 391.82 u;对小于3 ku样品经阳离子交换层析并采用pH 9和pH 2两种缓冲液进行反相高效液相层析分离纯化,获得一个抗菌肽,质谱分析其分子量为839.19 u。研究表明,日本鳗鲡脾脏中起抗菌活性的主要成分是一些小分子蛋白。 相似文献
10.
应用反向高效液相色谱法(RP-HPLC)从中华绒螯蟹脑组织提取液初步分离了促性腺释放激素(GnRH)类似物,使用章鱼促性腺释放激素抗体(anti-octGnRH)对分离组分进行免疫斑点印迹实验鉴定,获得了免疫反应呈阳性分离组分,表明脑组织粗提液中含有GnRH类似物分离组分。对该GnRH类似物进行基质辅助激光解吸/电离串联飞行时间质谱(MALDI-TOF/TOFMS)分析,结果显示多肽物质分子量范围在800～1400u,主要由8种小分子多肽组成,其中一种组分的分子量与章鱼促性腺释放激素(octGnRH)分子量接近。 相似文献
11.
Functional hermaphroditism in teleosts 总被引：1，自引：0，他引：1
Teleost fishes are characterized by a diversity of sexual patterns. Hermaphroditism, the expression of both male and female reproductive function in a single individual, generates the most curiosity and controversy. Yet diagnosis of this form of sexuality continues to challenge workers, in particular the distinction between functional and non‐functional hermaphroditism. This distinction, reflected as it is in the relationships between gonad form and function, is important if we wish to improve our understanding of the origin of hermaphroditism in the teleosts and of its highly sporadic expression today. Although structure can indicate phylogenetic affinities, it does not always reflect reproductive function, and function is important for understanding adaptation. With resurgent interest in hermaphroditism comes the recognition that understanding sexual pattern is not only important for better knowledge of reproductive biology and ecology but may also elucidate phylogenetic relationships. On the basis of a conservative and clearly defined set of diagnostic criteria, which incorporate new accounts of hermaphroditic species, and by applying an improved understanding of gonadal ontogeny, a comprehensive review and careful re‐examination of all primary literature was conducted. This overview documents the incidence of hermaphroditism in teleosts and explores its phylogenetic distribution, possible origin and range of expression. The review confirms functional hermaphroditism in 27 teleost families in seven orders, predominantly among tropical, marine perciforms in which its diversity of expression is greatest. In families with functional hermaphrodites, the sexual pattern is widespread and often highly variable in expression, even within a single genus or between populations. Based on our understanding of gonadal ontogeny in teleosts and on known phylogenetic interrelationships, the origin of functional hermaphroditism is most parsimoniously explained by a proto‐hermaphroditic condition in teleosts and cyclostomes, constituting a hermaphroditic potential for these groups. Exploitation and expression of this potential appear to be a response to a suite of environmental and biological factors, opportunities and constraints that result in the independent appearance of the hermaphroditic option in many different fish lineages. 相似文献
12.
红鲤4群体间主要组织相容性复合体的差异 总被引：9，自引：2，他引：9
应用鱼类主要组织相容性复合体(MIC)基因来探讨鱼类种群间遗传结构,寻找分子遗传标记。根据已报道的鲤鱼MICI类基因序列,设计了一对特异性引物,从兴国红鲤、荷包红鲤、玻璃红鲤及瓯江彩鲤基因组DNA中扩增了编码MICI类分子α2链的基因片段,并进行克隆、测序。结果表明,(1)编码MHC I类分子α2链的基因多态性较为丰富,234bp长度中有106个变异位点,多态位点百分率达45．3％;荷包红鲤的基因序列与其它3群体红鲤有显著差异;(2)由编码MICI类分子α2链的基因和氨基酸序列构建的系统进化树一致,兴国红鲤与团江彩鲤关系较近,属于同一进化支,玻璃红鲤和荷包红鲤分别属于另外两个不同的进化支,荷包红鲤是较为特化的群体;(3)多态性丰富的编码MICI类分子α2链的基因,适宜作为鲤鱼不同群体的分子遗传标记。 相似文献
13.
对虾抗病性状遗传标记的RAPD分析 总被引：20，自引：1，他引：20
对人工选育的第3代中国对虾和选育的第1代凡纳对虾进行个体人工感染WSSV后，选取感染WSSV十余天但仍健康的对虾为实验材料，用220个随机引物进行RAPD分析，得到抗病性状相关的特异性遗传标记99个。其中中国对虾抗病组特异性片段出现了18个，片段大小在460－2305bp之间；凡纳对虾抗病组特异性片段产生81个，片段大小在435－2287bp。77个引物在两种对虾的抗病组扩增出特异性遗传标记，其中有4个引物各获得了三个特异性片段，有13个引物各获得了两个特异性片段，其余61个引物各获得了1个特异性片段。 相似文献
14.
Development of microparticle diets for Japanese flounder Paralichthys olivaceus larvae 总被引：2，自引：0，他引：2
Toshio TAKEUCHI Qiurong WANG Hirofumi FURUITA Tetsuya HIROTA Shuzo ISHIDA Hirotoshi HAYASAWA 《Fisheries Science》2003,69(3):547-554
ABSTRACT: Two newly designed microparticle diets (MD), with two kinds of peptide (C700 and C800) as a protein source were developed. Microparticle diet Q (MD-Q) contained C700 (molecular weight ∼30 000 Da) and C800 (molecular weight 1000–2000 Da); in contrast, microparticle diet T (MD-T) contained C700 only. Two separate trials, representing larvae from different hatches, were conducted. Japanese flounder Paralichthys olivaceus larvae were fed newly designed MD or a combination of them with live food (LF) between 3 and 10 days after hatching (d.a.h.) in experiment I, or between 11 and 20 d.a.h. in experiment II, and compared them to LF and a commercial diet (CD) feeding groups. The growth and survival rates in both experiments were the highest in the LF treatment. But in the microparticle treatment larvae fed MD-Q had a higher survival rate and better growth than those fed MD-T, either alone or in combination with LF. First-feeding larvae fed on MD-Q had a 20.5% survival rate and 1.12 mm gain by 10 d.a.h. Unfed larvae died within 6 d.a.h. These results indicate that using a mixture of different molecular weight peptides is good protein sources and also this type of microparticle diet can be applied to flounder from larval to juvenile stages. 相似文献
15.
16.
Marteilia refringens is a protozoan parasite causing a disease notifiable to the Office International des Epizooties (OIE) and its distribution has implications for the transfer of live animals. The internal transcribed spacer-1 (ITS-1) from Marteilia clones contains polymorphism. Digestion with HhaI reveals two different restriction profiles, previously referred as 'O' (Marteilia from oyster or Marteilia refringens) and 'M' (Marteilia from mussels or Marteilia maurini). The aim of the present work was to determine whether the two previously described Marteilia molecular types (O and M) exist in the Iberian Peninsula and the strictness of the association with their bivalve host species. The sequence variability in the ITS-1 of Marteilia species was studied in mussels, Mytilus galloprovincialis, and flat oysters, Ostrea edulis, from different geographical locations in Spain, to establish the existence and the distribution of different species or molecular types. Although there were two distinct evolutionary lineages that corresponded more or less strictly with the 'M' and 'O' types, it was evident from the estimated phylogeny that some 'O' types have switched to 'M' type, and vice versa. Moreover, 'O' types were found in mussels and 'M' types were found in oysters, which suggests that there have been several cross-species transmissions of Marteilia between mussels and oysters. 相似文献
17.
翘嘴鳜微卫星标记及其与主要经济性状的相关分析 总被引：1，自引：0，他引：1
利用筛选出的7对具有较高多态性的微卫星标记,检测106尾翘嘴鳜Siniperca chuatsi选育个体的基因组DNA,分析这些微卫星标记与翘嘴鳜体长、体质量和体高的相关性。结果获得67个等位基因,各位点的等位基因数为3~19,片段大小在147~530bp之间;期望杂合度0.5092~0.9207,均值为0.7574;各位点的多态信息含量在0.4639~0.9101之间,均值为0.7197,表明所选择的SSR标记识别力较高,适用于翘嘴鳜选育群体遗传分析和标记辅助育种研究。相关性分析结果表明,G4位点中含有的片段为219bp等位基因的基因型(229/219或219/219)个体的体质量、体长和体高的表型效应显著高于其他的基因型,G10位点中246/246基因型的体质量和体高表型效应显著高于其他基因型,可作为未来翘嘴鳜分子标记辅助育种的重要参考位点。 相似文献
18.
将经过不同酶解方式处理的肽聚糖制剂配制成饲料投喂凡纳滨对虾（Litopenaeus vannamei），测定不同肽聚糖对对虾血清酚氧化酶和酸性磷酸酶的影响并分析不同酶解处理组肽聚糖制剂中的成分及其含量。肽聚糖制剂成分分析结果显示，经72h溶菌酶水解的肽聚糖制剂的低分子量肽聚糖含量较经过24h水解的肽聚糖制剂高，且蛋白酶的水解作用可促进溶菌酶的水解作用。对虾血清酶活力结果显示，对于提高对虾的酚氧化酶及酸性磷酸酶活力，酶解后的肽聚糖制剂比未经酶解的肽聚糖制剂效果明显，且含有较多低分子量肽聚糖的制剂组的效果优于含有较少低分子量肽聚糖的制剂组。实验结果表明，肽聚糖的免疫增强活性与肽聚糖分子量的大小相关，肽聚糖制剂中低聚糖含量的增加会提高其免疫增强效果。[中国水产科学，2006，13（4）：631—636] 相似文献
19.
Yan-Fei Liu Fa-Wen Yin Yu-Xin Liu Zi-Xuan Wu Jing Zhang Qi Zhao 《Journal Of Aquatic Food Product Technology》2019,28(4):342-351
In this study, the molecular species of glycerophosphocholine (GPCho), glycerophosphoethanolamine (GPEtn), glycerophosphoserine (GPSer), glycerophosphatidylinositol (GPIns), lysoglycerophosphocholine (LGPCho), and lysoglycerophosphoethanolamine (LGPEtn) from arcidaes Scapharca subcrenata and Scapharca broughtonii were characterized using direct infusion-tandem mass (shotgun) method for the first time. At least 201 and 303 glycerophospholipid (GP) molecular species were characterized, respectively. Most of the predominant GP molecular species contained polyunsaturated fatty acids (PUFA), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Meanwhile, the arcidae lipids contained a high proportion of polar lipids (81.57–86.72% of total lipids). Among PL, phosphatidylcholine (30.53–32.04 mol%) and phosphatidylethanolamine (21.48–26.71 mol%) were dominant. 相似文献
20.
Dr. Jeffrey R. Hazel 《Fish physiology and biochemistry》1996,15(3):195-204
Most previous studies of the temperature-induced restructuring of phospholipid molecular species composition have examined steps in the biosynthesis of phospholipids to explain the accumulation of unsaturated fatty acids in membranes of cold-acclimated poikilotherms. In contrast, the present study explores the role of phospholipases in this restructuring process by determining the rates of degradation of specific molecular species of phosphatidylcholine, using enzymes (microsomes) freshly isolated from the liver of rainbow trout. (Oncorhynchus mykiss) acclimated to either 5° or 20°C. The substrate preparation employed to assay phospholipase activity possessed a range of molecular species, all radiolabeled with 1-14C-palmitic acid at thesn-1 position, similar to that present in native trout liver microsomes. After defined periods of incubation (120 and 240 min at 5°C; 60 and 120 min at 20°C), phospholipids were extracted from the reaction mixture and the distribution of radioactivity among the molecular species of phosphatidylcholine was determined by HPLC/liquid scintillation counting. In general, molecular species catabolism was not significantly influenced by either assay or acclimation temperature. Only in 20°C-acclimated fish did a reduction in assay temperature (from to 20 to 5°C) result in significantly increased proportions of radioactivity being recovered in one polyunsaturated fatty acid-containing species (16:0/22:6-PC). It is concluded: 1) that phospholipase specificity, assayed under conditions approximating thosein situ, is not significantly influenced by temperature; and 2), that the increased proportions of unsaturated fatty acid-containing molecular species of phosphatidylcholine observed at low temperatures must reflect the specificity of biosynthetic rather than degradative processes. 相似文献