共查询到20条相似文献，搜索用时 93 毫秒
1.
从自然海区捕获的三疣梭子蟹(Portunus trituberculatus)上检测到一种寄生性原生动物,主要寄生于蟹血淋巴液中。通过普通光学显微镜检发现,病蟹的血淋巴细胞急剧减少,代之以大量的原生动物,此原生动物可以被中性红染液着色。运用PCR技术对该原生动物进行了18S rDNA基因和ITS1-5.8S rDNA-ITS2基因序列扩增,同时对扩增片段进行了序列测定,应用软件MEGA 3.1和DNAStar对测序结果进行了同源性比较和系统发育树构建。18S rDNA同源性比较结果显示:获得的18S rDNA序列与动基体目(Kinetoplastida)新波豆科(Neobodonidae)新波豆属(Neobodo)的同源性最高,达88.3%;获得的18S rDNA序列和GenBank中已登录新波豆属的其它原虫的18S rDNA序列在系统发育树中位于同一集群,初步确定该原生动物为新波豆虫(Neobodo sp.),是原生动物门(Protozoa)鞭毛虫纲(Flagellata)动基体目新波豆虫科新波豆属的一员。 相似文献
2.
采用PCR扩增技术对三疣梭子蟹日本北海道群体、韩国东海岸群体和我国山东即墨市会场村群体3个野生群体的16S rRNA和COI基因片段进行了扩增和测序,分别得到了长度为523和658bp的片段。通过统计变异位点、平均核苷酸差异数和核苷酸多样性指数,分析比较了不同群体间的序列差异和遗传多样性水平。结果显示,我国会场三疣梭子蟹野生群体的遗传多样性水平较低。用MEGA4.0软件中的NJ法构建的分子进化树,基于16S rRNA片段构建的NJ系统树所反映的分类关系与基于COI基因片段构建的系统树并不一致,主要不同在于与日本蟳的分类关系上,基于16S rRNA基因片段构建的NJ系统树显示梭子蟹科的3个属聚为两大支:三疣梭子蟹不同的单倍型先聚在一起,再和梭子蟹属的远海梭子蟹及塞氏梭子蟹聚为一支;而青蟹属的3种蟹先聚在一起,再和日本蟳聚为一支。而基于COI基因片段构建的系统树显示,梭子蟹属先与青蟹属的两种蟹聚为一支,然后再与日本蟳聚在一起。本研究共发现19种单倍型,我国会场群体与日本北海道群体、韩国东海岸群体均有共享单倍型,表明我国会场群体与国外两个野生群体的遗传背景相似。这些资料为我国三疣梭子蟹的种质资源保护和利用提供了基础的分子生物学依据。 相似文献
3.
《渔业科学进展》2017,(2)
为初步研究三疣梭子蟹(Portunus trituberculatus)几丁质酶PtCht3的生物学功能,利用特异性引物扩增和SMART~(TM) RACE技术克隆获得三疣梭子蟹PtCht3基因全长c DNA序列,并对该序列进行分析。结果显示,三疣梭子蟹PtCht3基因全长为1409 bp,对PtCht3基因序列推导出的氨基酸序列进行分析可知,该基因编码由394个氨基酸组成的蛋白质,预测分子量为43.67 kDa,理论等电点为4.80。PtCht3蛋白亲水性总平均数为-0.097,属于稳定蛋白。同源性和系统进化分析发现,PtCht3与日本仿长额虾(Pandalopsis japonica)和中华绒螯蟹(Eriocheir sinensis)几丁质酶3的同源性分别为54%和53%,与其他甲壳动物几丁质酶3聚为一支。RT-PCR显示,PtCht3基因具有较强的组织表达特异性,在肝胰腺中的相对表达量最高,在三疣梭子蟹蜕皮前期表达上调,低盐胁迫后在鳃和肝胰腺中表达量出现了波动,总体呈先上升后下降的表达趋势。推测PtCht3可能在三疣梭子蟹消化和蜕皮过程中发挥重要作用,参与三疣梭子蟹渗透压调节进程。本研究为三疣梭子蟹几丁质酶的功能研究提供了重要信息。 相似文献
4.
为初步研究三疣梭子蟹(Portunus trituberculatus)几丁质酶PtCht3的生物学功能,利用特异性引物扩增和SMARTTM RACE技术克隆获得三疣梭子蟹PtCht3基因全长cDNA序列,并对该序列进行分析.结果显示,三疣梭子蟹PtCht3基因全长为1409 bp,对PtCht3基因序列推导出的氨基酸序列进行分析可知,该基因编码由394个氨基酸组成的蛋白质,预测分子量为43.67 kDa,理论等电点为4.80.PtCht3蛋白亲水性总平均数为-0.097,属于稳定蛋白.同源性和系统进化分析发现,PtCht3与日本仿长额虾(Pandalopsis japonica)和中华绒螯蟹(Eriocheir sinensis)几丁质酶3的同源性分别为54％和53％,与其他甲壳动物几丁质酶3聚为一支.RT-PCR显示,PtCht3基因具有较强的组织表达特异性,在肝胰腺中的相对表达量最高,在三疣梭子蟹蜕皮前期表达上调,低盐胁迫后在鳃和肝胰腺中表达量出现了波动,总体呈先上升后下降的表达趋势.推测PtCht3可能在三疣梭子蟹消化和蜕皮过程中发挥重要作用,参与三疣梭子蟹渗透压调节进程.本研究为三疣梭子蟹几丁质酶的功能研究提供了重要信息. 相似文献
5.
为研究中华虎头蟹野生群体的种质资源及遗传多样性状况,采用PCR扩增获得中华虎头蟹线粒体DNA的16S rRNA和COⅠ基因片段,分别对其进行序列比较及系统进化分析。16S rRNA和COⅠ基因片段的A+T平均含量分别为67.7%和61.4%,A+T含量显著高于G+C含量。长度为515 bp的16S rRNA基因片段共检测出单倍型4种,多态性位点4个,均为单一变异位点;长度为653 bp的COⅠ基因片段共检测出单倍型11种,多态性位点23个,其中简约信息位点5个和单一变异位点18个。COⅠ基因片段比16S rRNA基因片段具有较大的变异,更适于中华虎头蟹种群的遗传多样性分析。基于16S rRNA和COⅠ基因片段的遗传距离与系统进化分析结果一致,表明中华虎头蟹与梭子蟹科的蟹类亲缘关系最近,方蟹科与沙蟹科的蟹类聚为一支,与传统分类结果基本一致;而脊椎动物2个基因片段的系统进化分析结果不一致。根据16S rRNA基因片段的遗传距离推测出4科7种蟹的大致分化时间发生在古新世至始新世。 相似文献
6.
取健康三疣梭子蟹(Portunus trituberculatus)‘黄选1号’80日龄幼蟹,体重(32.66±6.27)g。通过RT-PCR及Smart-TM Race技术,克隆了三疣梭子蟹谷胱甘肽S-转移酶(glutathiones-transferase,简称GST)基因c DNA全长序列(Gen Bank登录号:KF781517)。GST基因全长1 010 bp,编码一个由216个氨基酸组成的多肽,预测理论等电点PI为5.294,分子量为24.59 k D。氨基酸序列中含有GST基因家族特有GST-N结构域和GST-C结构域。同源性及系统进化分析表明,三疣梭子蟹GST基因与中华绒螯蟹(Eriocheir sinesis)和脊尾白虾(Exopalaemon carinicauda)的同源性分别为78%和63%。实时荧光定量PCR结果表明,GST基因在肝胰腺、鳃、肌肉、血淋巴、心脏和眼柄中均有分布,在肝胰腺中表达量最高(P0.05),其次是鳃(P0.05),在心脏中表达最少。三疣梭子蟹肌肉注射低、中、高3个剂量组的磺胺嘧啶后,GST基因表达较对照组都有表达,均呈现先升高后降低再升高的趋势。同时,随着药物浓度的增加,低、中、高3个剂量组峰值出现的时间越晚,分别为6 h、24 h和48 h。本实验结果表明,磺胺嘧啶可以诱导三疣梭子蟹GST基因表达,GST基因可能参与三疣梭子蟹的药物代谢反应。 相似文献
7.
用DNAExtractionKit提取草鱼(Ctenopharyngodonidella)肝脏的总DNA,合成特异引物,进行PCR扩增。扩增产物经琼脂糖电泳检测、纯化后克隆到pGEM Teasyvectorsystem的T载体上,筛选转化子,提取质粒,酶切鉴定。重组质粒序列测定的结果显示克隆了草鱼线粒体细胞色素b(cytb)基因1140个碱基及两侧部分序列共1254bp。用DNA分析软件VectorNTI6.0比较草鱼与GenBank中18种鱼类cytb的序列,显示草鱼与它们的cytb基因具有较高的同源性;根据草鱼与这18种鱼的cytb基因序列同源性所建立的进化树,与传统的分类地位基本吻合。 相似文献
8.
三疣梭子蟹病原弗氏柠檬酸杆菌的分离鉴定及定居因子抗原基因检测 总被引：4，自引：1，他引：3
2009年10月江苏赣榆地区某养殖场养殖的三疣梭子蟹出现大量死亡,症状主要表现为:病蟹行动缓慢、不摄食,蟹体消瘦,打开头胸甲可见肝胰腺、鳃、肌肉等内脏组织水肿,部分肝胰腺和肌肉组织呈腐烂状。从患病梭子蟹肌肉、肝胰脏、体内积液中分离到大量优势生长的细菌。人工感染试验,证明分离菌(JG091120-1)对健康三疣梭子蟹具有很强的致病性。对分离菌进行了形态特征、理化特性等常规表型生物学检验,同时利用分子生物学方法测定了代表菌株的16S rRNA和gyrB基因序列,其中分离菌16S rRNA基因序列长度为1 451 bp(登录号HQ170626),gyrB基因序列长度为1 186 bp(登录号HQ170627),分析了16S rRNA和gyrB两种基因序列的同源性。根据分离菌的表型及分子生物学特性,判定该菌为肠杆菌科枸橼酸属的弗氏柠檬酸杆菌。定居因子抗原cfa是肠杆菌科产肠毒素细菌的一种重要致病因子,利用特异性引物进行cfa基因的PCR扩增,分离菌可以扩增出大小在100 bp的基因片段,表明本次分离的病原弗氏柠檬酸杆菌具有cfa毒力因子。 相似文献
9.
三疣梭子蟹Sox基因HMG盒的克隆分析 总被引：1，自引：0，他引：1
利用能扩增人类SRY基因HMG盒的一对简并引物,分别对三疣梭子蟹雌雄个体基因组DNA进行扩增,均得到216 bp和约400 bp的两条带,不存在性别差异,通过PCR-SSCP分析,未发现雌蟹或雄蟹所特有的Sox基因。对216 bp的带进行克隆测序得到6个Sox基因,分别命名为PTSox21、PTSox12、PTSox11a、PTSox11b、PTSox11c和PTSox4。其中,PTSox21、PTSox12和PTSox4氨基酸序列与人类Sox21、Sox12和Sox4基因的同源性分别为90%、66%和63%,PTSox11a、PTSox11b和PTSox11c氨基酸序列均与人类Sox11基因有63%的同源性。此外,PTSox11a和PTSox11b的氨基酸序列之间的同源性达到了98.6%,只在第44位氨基酸残基不同。与其他物种Sox基因氨基酸序列的同源性比较发现,PTSox21与饰纹姬蛙Sox2a有92%的同源性,而PTSox12、PTSox11a、PTSox11b和PTSox11c均与意大利蜜蜂的Sox1有73%的同源性,PTSox4与意大利蜜蜂的Sox1有72%的同源性。 相似文献
10.
从三疣梭子蟹育苗场发病且大量死亡的大眼幼体中分离到优势生长的菌株SX1,人工感染试验证明,SX1对健康三疣梭子蟹大眼幼体及Ⅲ期幼蟹有较强的致病性;对菌株SX1进行了形态特征、理化特性等表型生物学特性检验,并进行了菌株SX1的16S rRNA、gyrB和rpoA 3种基因的同源性检索与系统发育学分析。结果显示,菌株SX1具有发光杆菌属的特征,且16S rRNA、gyrB和rpoA 3种基因序列均与发光杆菌具有较高的同源性,在系统发育树中与Photobacteriumganghwense聚为一个分支,自举数据值达100%。综合菌株SX1的形态特征、理化特性及3种基因的同源性检索与系统发育学分析,研究表明菌株SX1与P.ganghwense亲缘关系更近,鉴定SX1为P.ganghwense且为本次引起三疣梭子蟹大眼幼体大量死亡的病原菌。 相似文献
11.
12.
为了对4种不同开口大小的六边形开口方形人工鱼礁在4种迎流角度下数值模拟和水槽模型试验的阻力系数进行对比验证,分别利用水槽模型和数值模拟试验方法对4种不同开口比（γty=0.0625,0.14,0.25,0.39）六边形开口方形人工鱼礁在4种迎流角度（θ=0°,15°,30°,45°）状态下的阻力进行测定,并计算两种方法的阻力系数。结果表明：（1）在数值模拟和水槽模型试验中,人工鱼礁模型阻力均随着开口比的增大而减小;礁体迎流角度的变化可改变礁体阻力,且在4种迎流角度下,人工鱼礁阻力在θ=30°时最大。（2）人工鱼礁数值模拟与水槽模型试验中,当θ为15°、30°和45°时,阻力系数均随着开口比的增加而增加,具有明显的线性关系,且阻力系数在迎流角度θ=30°时最大。（3）数值模拟与模型试验阻力的相对误差在0.12%~17.18%,平均误差7.43%;礁体阻力系数的相对误差在0.03%~14.64%,平均误差5.26%。阻力及阻力系数误差均在20%以下。水槽模型试验与数值模拟阻力和阻力系数相关系数R分别为0.99和0.80,P<0.001,具有极强的相关性。因此,利用数值模拟精细化研究人工鱼礁水动力性能是可行的。 相似文献
13.
Michael H. Meeuwig Christopher S. Guy Wade A. Fredenberg 《Ecology of Freshwater Fish》2011,20(2):315-325
Abstract – Bull trout, a species of char listed as threatened under the US Endangered Species Act, have been displaced from portions of their historic range following the introduction of nonnative lake trout. It has been suggested that competitive exclusion as a result of trophic overlap between bull trout and lake trout may be the causal mechanism associated with displacement of bull trout. This study used stable isotope data to evaluate trophic relationships among native bull trout, nonnative lake trout and other fishes in seven lakes in Glacier National Park (GNP), Montana. Bull trout and lake trout had greater δ15N values relative to other fishes among lakes (δ15N ≥ 3.0‰). Lake trout had greater δ15N values relative to bull trout (δ15N = +1.0‰). Bull trout had greater δ13C values relative to lake trout in six of the seven lakes examined. Although both bull trout and lake trout had greater δ15N values relative to other fishes within lakes in GNP, differences in δ15N and δ13C between bull trout and lake trout suggest that they are consuming different prey species or similar prey species in different proportions. Therefore, displacement of bull trout as a direct result of complete overlap in food resource use is not anticipated unless diet shifts occur or food resources become limiting. Additionally, future studies should evaluate food habits to identify important prey species and sources of partial dietary overlap between bull trout and lake trout. 相似文献
14.
Yukihiro Kitade Michiko Nakamura Hirotoshi Endo Satoru Fukuda Kazuyoshi Kuwano Naotsune Saga 《Fisheries Science》2006,72(3):639-645
ABSTRACT: A cDNA ( PyARP4 ) containing an open reading frame for a protein of 573 amino acids was identified in the marine red alga Porphyra yezoensis . The conceptual PyARP4 protein exhibits significant similarity to actin-related protein (ARP) 4 in the terrestrial plant Arabidopsis . Comparison of the deduced amino acid sequence showed moderate sequence identity (30%) to a conventional actin in P. yezoensis , as seen in comparisons between ARP and conventional actins of other organisms. A putative bipartite nuclear localization signal and an actin motif were found within the PyARP4 amino acid sequence. In a phylogenetic analysis, the PyARP4 was found to cluster with the ARP4 of other organisms. The expression level of PyARP4 did not change significantly among four developmental stages of life cycle and was lower than that of a conventional actin. This cDNA therefore may serve as a useful internal standard in gene expression analyses of differentially expressed genes in P. yezoensis . 相似文献
15.
16.
山区水库网箱养殖黄颡鱼试验 总被引：1，自引：0，他引：1
网箱面积30 m2,底部设饲料托盘。黄颡鱼规格46.3 g/尾,先用动物性饵料驯食1个月,后投喂粗蛋白质量分数38%颗粒饵料。加强管理,药物预防鱼病。黄颡鱼成活率87%,平均规格206 g/尾,平均单产19.6 kg/m2,利润284.8元/m2。 相似文献
17.
Sarah C. F. Hawkshaw Michael P. Gillingham J. Mark Shrimpton 《Ecology of Freshwater Fish》2014,23(3):383-394
Flooding river valleys following construction of dams restrict fluvial environments to reaches that were formerly headwaters. Whether remaining habitat is suitable for all life stages of fluvial species is poorly understood. A fluvial species, Arctic grayling Thymallus arcticus, showed a dramatic decline following flooding of the Upper Peace River and the formation of the Williston Reservoir. We related landscape and field site‐specific features with occurrence of juvenile Arctic grayling using an information theoretic approach. For the landscape model, an association was identified between stream order and Arctic grayling occurrence although stream order alone was a poor predictor. A positive association between juvenile Arctic grayling occurrence and distance from the Williston reservoir and stream order, as well as a negative association with water temperature and temperature variance, was deemed important for the field site model. Both modelling approaches indicated size of stream system to be an important influence on occurrence of juvenile grayling in the Williston watershed. River length required for suitable river habitat for salmonids has not previously been identified, but should be factored into future management plans when evaluating the impact of proposed hydroelectric dams and subsequent flooding of river systems. 相似文献
18.
We address the importance of the isoelectric point (IEP) of proteins and membrane components such as phospholipids for our
understanding and interpretation of isoforms and opposite charge interactions in the formation of complexes. Five examples
drawn from the literature are newly approached from the IEP point of view to clarify general principles. 相似文献
19.
20.
An experiment designed to measure the volume variation of a bag-net within a set-net was conducted in Jaran Bay, Kosung, Korea. Three radio-acoustic-linked positioning (RAP) buoys, a time controller with a personal computer and seven pingers were used to measure the volumes of the bags. During the April neap tide, the minimum and maximum volumes of the bag-net were 4173 m3 (at 17.00 h) and 4757 m3 (12.00 h), respectively. The average current directions and speeds were 99.9°, 12.9 cm/s and 104.0°, 2.4 cm/s, respectively. During the spring tide, the minimum and maximum volumes of the bag-net were 2016 m3 (18.30 h) and 4454 m3 (15.00 h), respectively. The average current directions and speeds were 315.6°, 16.1 cm/s and 289.0°, 5.7 cm/s, respectively. The minimum (2016 m3) and maximum (5568 m3) volumes of the bag-net were observed during the period when the spring tide changed to the neap tide. 相似文献