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1.
通过同源基因克隆方法得到双棘黄姑鱼促性腺激素释放激素(GnRH)的3个基因:cGnRH、sGnRH、sbGnRH,其开放阅读框为258、273bp和261bp,分别编码85个、90个和86个氨基酸,3个基因的信号肽为23个氨基酸,核心十肽分别是QHWSHGWYPG、QHWSYGWLPG和QHWSYGLSPG,这3种核心十肽经生物信息学分析均高度保守。氨基酸序列比对分析表明,双棘黄姑鱼与同科美国红鱼GnRHs基因亲缘性最近,它们的cGnRH和sGnRH的氨基酸同源性达100%,两种鱼sbGnRH的同源性也高达92.2%。用MEGA 4.0构建GnRHs Neighbour-joining系统进化树,结果显示双棘黄姑鱼cGnRH先于同科的美国红鱼聚类,再与星点东方鲀、斑马鱼和虹鳟等共同聚类;双棘黄姑鱼sGnRH则先后与其他鱼类sGnRH、cGnRH、sbGnRH聚类;而双棘黄姑鱼sbGnRH先后与其他鱼类的sbGnRH、cGnRH和sGnRH聚类。  相似文献   

2.
磷脂氢谷胱甘肽过氧化物酶(Phospholipid hydroperoxide Glutathione Peroxidase, PHGPx)是GPx基因家族的重要一员,能特异地清除磷脂和胆固醇等氢过氧化物,在机体抗氧化、抗凋亡、抗炎症以及雄性性成熟等过程中发挥着重要的作用。本研究从实验室拟穴青蟹(Scylla Paramamosain)转录组数据库中筛选出该基因的EST序列,利用SMART-RACE 技术克隆得到该基因的全长cDNA。经Blast 比对后,其与丰年虾(Artemia franciscana)的PHGPx氨基酸序列一致性最高,达到69%。同时系统进化树分析表明,该基因与其他物种的PHGPx(GPx4)聚为一支,而与GPx1、GPx2等亚型距离较远,故命名该基因为Sp-PHGPx。实时定量PCR结果显示,Sp-PHGPx在成熟青蟹雌雄各组织中均有不同程度的表达,其中精巢的表达量最高;且在雌雄相同组织中,雌性性腺的表达量显著低于雄性;而在鳃和心脏中的表达量显著高于雄性。在性腺不同发育阶段,Sp-PHGPx在卵巢发育过程中的表达量差异不显著;而在精巢发育过程中,其表达量在精子细胞期(T2期)显著高于精母细胞期(T1期)和成熟精子期(T3期),同时也显著高于卵巢发育各时期的表达量。在LPS应激下,鳃和肝胰腺中Sp-PHGPx的表达量分别在6h和12h显著上调;H2O2应激下,鳃中的表达量在3 h显著升高,肝胰腺中的表达量在被检测的各时相中无显著差异。以上结果表明,Sp-PHGPx可能在免疫防御反应以及精巢的发育和成熟等过程中发挥着重要作用。  相似文献   

3.
为了研究17β-hsd4基因在无脊椎动物生殖过程中的作用,实验从栉孔扇贝转录组数据库中获得一个表达序列标签,采用cDNA末端快速扩增技术克隆得到1条全长为2 417 bp的cDNA序列,其开放阅读框为2 223 bp,编码740个氨基酸,推测的氨基酸序列含有17β-HSDs特有的4个保守区和17β3-HSD4的3个酶结构域,且与人等脊椎动物的序列相似性均在58％以上.半定量RT-PCR显示,该基因在栉孔扇贝精巢、卵巢、肌肉、外套膜、鳃、肝胰腺和肾脏等各组织中均有表达,其中在肝胰腺和肾脏中表达量明显高于其他组织.对不同发育时期性腺中该基因表达的qRT-PCR检测发现,其在精卵巢发育周期的表达模式不同,且在生长期和成熟期的精巢中表达量显著性高于同时期的卵巢.由此推测,栉孔扇贝多种组织中均可以合成17β-HSD4,在精巢的发育和成熟的作用明显高于卵巢.  相似文献   

4.
通过RACE方法获得半滑舌鳎(Cynoglossus semilaevis)Hh基因家族的Shh基因,该基因全长1 922 bp,其中5′UTR 266 bp,3′UTR 360 bp,ORF1 296 bp,编码431个氨基酸,经预测该多肽的相对分子质量为47.28 k D,理论等电点6.95,具有Hh基因家族特有的保守结构域。氨基酸序列分析表明,半滑舌鳎Shh与牙鲆的同源性最高,为82%,与其他鱼类同源性为74%~81%,与非洲爪蟾的同源性为61%,与人和鼠的同源性为63%~64%。甲基化结果显示,Shh基因在1龄卵巢中的甲基化程度普遍低于雄鱼与伪雄鱼精巢。基因表达分析显示,Shh基因在胚胎期的囊胚期表达显著高于其它时期(P0.05),在雌雄成鱼8个组织器官均表达,在雌性性腺分化的关键期孵化后50 d,雌性性腺中表达量较前期升高,且显著高于同时期雄性性腺中的表达(P0.05),在雄性性腺分化的关键期80~95 d,Shh基因在雄性中的表达水平显著升高(P0.05),在8月龄、1龄及2龄雌鱼性腺中表达显著高于雄鱼与伪雄鱼。本研究表明,半滑舌鳎Shh基因在进化中高度保守,与胚胎分化、组织器官形成、雌雄性腺分化及性腺发育密切相关。  相似文献   

5.
该研究克隆了大黄鱼(Larimichthys crocea)gsdf(gonadal soma derived factor)和amh(anti-Müllerian hormone)基因的开放阅读框序列并对它们的表达进行分析。大黄鱼gsdf基因c DNA序列开放阅读框长为618 bp,可编码205个氨基酸,含有信号肽和TGF-β结构域。系统进化分析显示,大黄鱼Gsdf与其他鱼类Gsdf聚为一枝,而与TGF-β超家族其他成员分开。Amh基因c DNA序列开放阅读框为1 563 bp,可编码520个氨基酸,含有信号肽、AMH-N区域和TGF-β保守结构域。系统进化分析显示,大黄鱼Amh与舌齿鲈(Dicentrarchus labrax)Amh进化关系最近。荧光定量PCR表达分析显示,gsdf和amh基因主要在大黄鱼性腺表达,在精巢中的表达量显著高于卵巢(P0.05),2个基因都在性腺分化前开始表达,在雄鱼精巢中表达量呈现先升高后下降的趋势,在卵巢的表达量很低。此外,相比于正常雌鱼,gsdf和amh基因在伪雄鱼(遗传性雌鱼)性腺中的表达量显著上调。这些结果表明,gsdf和amh基因在大黄鱼性腺分化过程中起到重要的作用。  相似文献   

6.
利用黄鳝(Monopterus albus)卵巢、间性性腺以及精巢转录组测序数据分析结果,筛选获得表达差异的LncRNA 54770.30。为探究黄鳝LncRNA 54770.30的生物学特性及其在性逆转过程中的功能和作用,本研究分析了黄鳝LncRNA 54770.30在不同组织与不同阶段性腺的表达。结果表明：LncRNA 54770.30在各组织均有表达,在肌肉中表达量最高,精巢与肝脏次之;LncRNA 54770.30在黄鳝卵巢至精巢转变过程中表达量呈上升趋势,卵巢与间性性腺中表达量无显著性差异,但卵巢、间性性腺与精巢中表达量呈显著性差异。利用原位杂交技术对LncRNA 54770.30在不同阶段性腺中表达进行定位分析,结果显示LncRNA 54770.30在黄鳝各阶段性腺中均有阳性信号,卵巢中主要在卵细胞的细胞质与颗粒细胞以及体细胞中表达;精巢中主要在初级精母细胞和次级精母细胞中表达。对黄鳝幼体进行甲基睾酮处理后,实验组卵巢结构出现明显退化,卵泡数量减少,出现中空小叶;荧光定量PCR分析显示,LncRNA 54770.30在实验组退化卵巢中的表达量较对照组显著下降。以上研究表明,...  相似文献   

7.
利用半滑舌鳎性腺转录组测序获得的StAR基因部分序列,设计RACE引物,克隆了半滑舌鳎StAR基因的cDNA序列,全长为1 294 bp,5'端UTR为132 bp,3'端UTR为310 bp,开放阅读框(ORF)为852 bp,共编码283个氨基酸。将半滑舌鳎StAR基因与其他物种StAR基因进行氨基酸同源性分析,结果显示,半滑舌鳎StAR与塞内加尔鳎、大口黑鲈、花鲈、金头鲷的同源性都达到了85%,与虹鳟、斜带石斑鱼及日本鳗鲡的同源性分别为81%、83%和76%。雌、雄鱼不同组织StAR基因的表达分析表明,StAR基因在雄鱼性腺中高表达,在雄鱼的肝脏、脑及心脏中表达量较低,而在雄鱼的其他组织中不表达;在雌鱼肠中不表达,在其他组织(卵巢、肝脏、脾脏、脑、垂体、肌肉、心脏、肾脏)中微量表达。荧光定量PCR分析不同组织与不同时期性腺表达谱表明,雄鱼性腺中StAR基因的表达量显著高于雌、雄鱼其他各组织(P0.05),提示StAR基因对雄鱼精巢发育起重要作用。雄鱼不同时期表达谱分析结果显示,StAR基因在66天前的精巢中不表达,在150天时表达量急剧增加,至2龄时表达量最高,3龄时表达量下降,说明该基因在精巢发育成熟过程中起重要作用。原位杂交结果显示,StAR基因主要在雄鱼精巢的精子细胞中表达,而在雌鱼的卵巢中不表达。研究表明,StAR基因在半滑舌鳎精巢发育中发挥作用,且可能在精子形成中发挥重要作用。  相似文献   

8.
本研究采用SMART RACE方法克隆了三疣梭子蟹(Portunus trituberculatus)Dnmt2(Pt Dnmt2)基因。该基因c DNA全长为1291 bp,开放阅读框为1203 bp,编码400个氨基酸。结构域分析显示,PtDnmt2基因有典型的C5-DNA甲基化酶结构域。同源分析表明,PtDnmt2氨基酸序列与其他物种有较高的同源性。系统进化分析显示,三疣梭子蟹PtDnmt2氨基酸序列与罗氏沼虾(Macrobrachium rosenbergii)Dnmt2关系最近。qRT-PCR结果显示,PtDnmt2基因在三疣梭子蟹所有组织中均有表达,在卵巢中表达量显著高于其他组织(P0.05)。PtDnmt2基因在胚胎和幼体发育过程中的表达量随发育时期而变化,其在受精卵和多细胞时期无表达,从囊胚期开始出现,随着胚胎的发育表达量逐渐上升。在性腺发育不同时期PtDnmt2基因表达量存在显著差异,其在卵巢II期表达量最高,之后逐渐下降;在精巢中该基因的表达量随着精巢的发育逐渐上升,在IV期达到峰值。本研究结果表明,PtDnmt2基因参与了三疣梭子蟹胚胎、幼体和性腺发育调控。  相似文献   

9.
本研究筛选到圆斑星鲽(Verasper variegatus)的性别相关基因sox9,并通过RACE技术获得了全长序列,基因全长为3287 bp,包括1431 bp的ORF,编码477个氨基酸,368 bp的5¢ UTR和1488 bp的3¢ UTR。在3¢ UTR中有多聚腺苷酸尾和加尾信号AATAAA。通过荧光定量PCR测定了sox9基因在圆斑星鲽成鱼不同组织中的表达水平,发现sox9基因在圆斑星鲽的脑、眼、鳃、心、肝、胆、肠、精巢、卵巢、肾和肌肉等各个组织中都有不同程度的表达。在鳃、脑和精巢组织中检测到较高水平的sox9转录,其中精巢中的转录水平显著高于其他组织,sox9基因在性腺中的表达显示出性别两相性差异。其在精巢中的表达水平要显著高于卵巢,说明sox9基因与雄性性腺发育相关。通过测定sox9基因在圆斑星鲽幼鱼不同发育时期(20、30、40、50、60、70和80日龄)的表达水平,发现其在20~50日龄表达量逐渐下降,在60日龄时表达量上升,推测表达量上升可能与幼鱼性腺分化相关。  相似文献   

10.
《海洋渔业》2021,43(4)
为研究栉孔扇贝(Chlamys farreri)FTZ-F1基因功能,对其序列特征和表达模式进行了分析。结果显示,该基因编码序列(coding sequences, CDS)长1 668bp,编码555个氨基酸,含DBD (DNA binding domain)保守区、FTZ-F1盒(FTZ-F1 box)、LBD(ligand binding domain)保守区,其保守区与其他物种较为一致。采用半定量PCR(RT-PCR)和荧光定量PCR(qRT-PCR)方法检测了FTZ-F1基因在栉孔扇贝中的表达,发现在雌性栉孔扇贝的闭壳肌、肾、鳃组织和雄性栉孔扇贝的精巢、肝胰腺、闭壳肌、肾中表达较强,在其他组织中表达较弱;在性腺发育周期中,FTZ-F1基因主要在成熟期精巢中表达,表达量显著高于其他时期性腺,表明FTZ-F1基因主要在成熟期精巢中发挥重要作用,推测可能与成熟期精巢睾酮含量升高相关。  相似文献   

11.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

12.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

13.
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14.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

15.
Growth hormone (GH) and reproduction: a review   总被引：5，自引：0，他引：5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

16.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

17.
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).  相似文献   

18.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

19.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

20.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future.  相似文献   

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