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1.
为探明长江中下游不同湖泊中短颌鲚(Coilia brachygnathus)遗传多样性水平和遗传分化程度,以洞庭湖、长湖、巢湖3个地理群体作为研究对象,采用线粒体控制区序列为分子标记,分别应用软件Dna SP 5.0、Arlequin3.1.1、MEGA5.0和Network 5.1进行了遗传参数统计和单倍型间分子变异分析(AMOVA),构建邻接系统树及单倍型网络图。对长江中下游短颌鲚野生群体的遗传多样性和遗传结构进行分析。结果显示,用来分析的1 236 bp D-loop区序列中共90个变异位点,54个简约信息位点。长江中下游3个地理群体中共发现58个单倍型,单倍型多样性(h)范围0.949~0.982,核苷酸多样性范围0.004 99~0.006 21,说明长江中下游3个湖泊短颌鲚地理群体具有较高的遗传多样性水平。3个短颌鲚地理群体遗传分化指数(Fst)为0.265 95,呈现出中等程度的分化水平,主要表现在巢湖群体与其他群体之间处于中等程度分化水平。依据遗传距离构建系统发育树及单倍型网络图也出现相类似结果。  相似文献   

2.
采用PCR和DNA测序技术对贵州都柳江鲤(Cyprinus carpio)、鲫(Carassius auratus)和草鱼(Ctenopharyngodon idellus)种群的mtDNA控制区序列及遗传多样性进行了研究。获得了都柳江鲤、鲫和草鱼mtDNA控制区长度分别为899~901 bp、787 bp和901~905 bp的序列。该3种鱼类控制区碱基A、T含量较高,G含量最低。识别了该3种鱼类mtDNA控制区终止序列区、中央保守区和保守序列区等保守序列。其中,除CSB-2和CSB-3碱基组成相同外,其余核心序列碱基组成存在着差异。都柳江鲤、鲫和草鱼种群mtDNA控制区分别有24、24和11个多态位点,分属12、17和8个单倍型。都柳江鲤、鲫种群遗传多样性较高,草鱼种群遗传多样性较低。因此,有必要开展都柳江草鱼种群遗传多样性的保护。  相似文献   

3.
【目的】基于mtDNA COI和COⅡ的联合序列,探讨中国南方茶棍蓟马Dendrothrips minowai地理种群的遗传多样性与遗传分化。【方法】利用MEGA 6.0, DnaSP 5.10和Arlequin 3.5.2.2等软件对中国南方茶棍蓟马8个地理种群遗传多样性、遗传分化、基因流、分子变异及地理距离与遗传距离的相关性进行分析,并推断群体演化历史。【结果】茶棍蓟马mtDNA COI和COⅡ序列均具有明显的AT偏好性,COI和COⅡ联合序列的长度为1 146 bp,共有22个单倍型。中国南方茶棍蓟马总群体遗传多样性较高,表现出高单倍型多样性(Hd=0.924)和低核苷酸多样性(π=0.00600)。8个地理种群总群体的遗传分化程度高(FST=0.84830),基因交流水平低(Nm=0.040),群体可能由于遗传漂变而发生明显分化。AMOVA分析显示,茶棍蓟马种群的遗传变异主要来自组间种群(FCT=0.84922);Mantel检测显示地理距离与遗传距离存在显著的正相关(r=0.5029, P<0.01)。中性检验结果表明,除云南两个地理种群外的其他地理种群近期可能经历了种群扩张。【结论】中国南方茶棍蓟马地理种群遗传多样性较高,具有明显的遗传分化,基因交流较少;地理距离可能是影响茶棍蓟马地理种群遗传分化的主要因素之一。  相似文献   

4.
通过线粒体控制区序列的分析,研究采自中国南海及东海5个群体102尾细鳞鯻的遗传多样性。发现在962 bp序列中有205个变异位点,其中135个为简约信息位点,共定义102个单倍型。中国近海细鳞鯻总体呈现出较高的遗传多样性特征(Hd=1.000,Pi=0.022),其中博鳌最高(Hd=1.000,Pi=0.028),平潭最低(Hd=1.000,Pi=0.014)。不同地理群体间无明显分化,基因交流频繁(Fst=-0.014—0.041,P0.05);中性检验均为显著负值,推测在16.9万年—5.06万年前,即中-晚更新世出现种群扩张。系统邻接树和单倍型网络图均出现3个显著分化的谱系(谱系间Fst=0.508—0.698,P0.001;净遗传距离Da=0.024—0.031),且各谱系中均有不同地理来源的群体。3个谱系间分歧时间大约在1.07百万年—0.24百万年前,推测可能是更新世冰期边缘海的出现导致群体隔离而产生分化。谱系A(Lineage A)包含85.3%的个体,其总体遗传多样性较高(Hd=1.000,Pi=0.012),其中平潭最高(Hd=1.000,Pi=0.014),合浦最低(Hd=1.000,Pi=0.010);群体间Fst在-0.021—0.068之间,P0.005;AMOVA分析显示只有1.97%的变异来自于种群间,表明群体间也无明显分化;中性检验均为显著负值,推测在25.4万年—7.6万年前出现种群扩张。中国近海细鳞鯻主要受到中-晚更新世海侵和海退的影响而出现种群扩张使得谱系间发生二次接触,最终形成具有显著谱系结构但无地理分化的情况。  相似文献   

5.
为探究贵州从江及邻近的榕江、黎平和锦屏以及广西三江、湖南的通道和靖州等地稻田鲤Cyprinus carpio Linnaeus的遗传结构及系统关系, 研究基于mtDNA Cyt b基因测序技术对6个地理群体进行了分析。447尾稻田鲤中共界定出29种Cyt b基因序列单倍型, 结合NCBI中鲤同源序列的系统发育和序列比对分析表明, 从江及邻近苗侗族地区稻田鲤是一个含欧亚2大谱系、3个鲤亚种和多个母系血统成分的混合群体, 主体类群是华南鲤C. carpio rubrofuscus, 同时混有欧洲鲤C. carpio carpio和远东鲤C. carpio haematopterus, 遭受国内外鲤养殖品种的遗传渗析。遗传多样性分析显示, 欧洲鲤亚种群体为低Hd低π, 遗传多样性贫乏, 远东鲤和华南鲤2个亚种群体呈高Hd低π特点。华南鲤6个稻田群体除锦屏为低Hd低π外, 其余都为高Hd低π, 从江的Hd最高, 黎平的π最高。遗传分化和分子方差(AMOVA)分析显示, 谱系间和亚种间存在显著的遗传分化(P<0.001), 锦屏和三江与其他群体存在中等-高度的分化等级, 其余群体间分化较弱, 群体间变异贡献率为16.69%, 群体内为81.14%。综合分析表明, 从江及邻近地区稻田鲤群体间存在有限的遗传交流, 群体内和群体间有不同的遗传结构。研究丰富了该地区稻田鲤遗传背景资料, 可为湘黔桂交界苗侗族地区稻田鲤的种质资源鉴定与保护提供理论依据。  相似文献   

6.
基于线粒体COⅠ基因DNA条形码的中国鲚属物种有效性分析   总被引:2,自引:0,他引:2  
分析了150尾刀鲚Coilia nasus、湖鲚C.nasus taihuensis、短颌鲚C.brachygnathus、七丝鲚C.grayii及凤鲚C.mystus个体的COⅠ基因DNA条形码序列变异。结果显示,150条COⅠ基因条形码序列包含63种单倍型,单突变位点主要集中在100bp和600bp附近。刀鲚、短颌鲚和湖鲚群体间的遗传距离在0.253%~0.557%之间,显著低于COⅠ基因DNA条形码鉴别不同物种2%的遗传距离阈值,表明这3个群体应为同一物种。但是凤鲚两群体间的遗传距离为5.08%,大于2%的鉴别阈值,显示凤鲚两群体可能达到了种或亚种级差异水平。以日本鳀Engraulisjaponicus为外群,用邻接法、最大简约法和最大似然法构建了分子系统树显示,刀鲚、湖鲚和短颌鲚群体聚在一起,未能各自形成单系;凤鲚根据地理分布聚为两支;七丝鲚则聚成单系。研究表明COⅠ基因条形码技术可用于我国鲚属物种的鉴定。  相似文献   

7.
采用PCR技术获得了贵州7个南蝠(Ia io)自然种群42个个体的线粒体DNA控制区全序列,长度为1256~1340 bp.对控制区结构进行分析,识别了其延伸的终止结合序列区(包括ETAS1和ETAS2元件)、中央保守区(包括F、E、D、C、B元件)和保守序列区(包括CSB1、CSB2和CSB3元件);同时,在延伸的终止结合序列区还发现了若干能形成发夹结构的主体序列TACAT—ATGTA.在7个自然种群42个个体中共定义了16个单倍型.遗传多样性分析表明:贵州南蝠种群具有较高的单倍型多样性(h=0.945)和中等的核苷酸多样性(π=0.012).基因流、AMOVA和系统进化树分析表明贵州这7个南蝠自然群体间没有发生遗传分化.  相似文献   

8.
铜鱼线粒体控制区的序列变异和遗传多样性   总被引:6,自引:0,他引:6  
采用PCR和DNA测序技术研究长江中上游野生铜鱼的遗传多样性和群体遗传学特征,从9个采样点共获得100尾铜鱼,用于分析的线粒体DNA控制区的片段序列为946bp。在100个序列中,共检测出变异位点47个(其中增添/缺失位点8个),单倍型41种。9个地理群体的平均单倍型多样性(Hd)和平均核苷酸多样性(Pi)分别为0.9257±0.0162和0.004178±0.002337,表现出较贫乏的遗传多样性。群体间的分化指数(FST值)、平均基因流(Nm)、分子方差分析(AMOVA)和平均K2-P遗传距离均表明9个铜鱼地理群体间存在广泛的基因交流,未明显发生群体遗传分化。另外,共享单倍型比例较高,约为34%(14/41)。单倍型的UPGMA分子系统树和简约网络图显示单倍型的聚类与地理分群没有相关性。上述结果表明9个铜鱼地理群体属于同一种群。  相似文献   

9.
小飞鼠 (Pteromys volans) 为树栖夜行滑行类啮齿动物,在森林种子传播和维持生态系统平衡等方面发挥着重要的生态学作用。本研究利用mtDNA Cytb、控制区和nDNA微卫星3种分子标记,对黑龙江省张广才岭北部的小飞鼠种群进行遗传多样性与历史动态分析。检测出Cytb全序列 (1 140 bp) 的平均单倍型多样性为0.909,平均核苷酸多样性为0.616%;控制区全序列 (1 066 bp) 的平均单倍型多样性为0.945,平均核苷酸多样性为1.698%;微卫星检测出种群平均等位基因数13.167个,观测杂合度0.727,期望杂合度0.864,近交系数0.159。结果表明,小飞鼠种群遗传多样性丰富,但存在一定程度的杂合度不足和近亲繁殖;未检测到种群近期遗传瓶颈效应,种群内无遗传分化。高比例的稀有单倍型 (≥ 60%) 、低频率等位基因与近亲繁殖,提示未来种群面临遗传多样性下降的风险,建议加大对该物种的关注和保护力度。基于Cyt b基因的系统进化关系结果表明,小飞鼠存在3个明显的遗传谱系:远东、欧亚大陆北部和日本北海道,本研究中张广才岭和大兴安岭的样本单倍型归属为远东谱系。  相似文献   

10.
不同产地中华鳖的线粒体控制区序列分析及结构比较   总被引:2,自引:0,他引:2  
采用PCR特异引物,扩增了两产地中华鳖(Pelodiscus sinensis)个体的mtDNA控制区(CR)及其邻近片段,测序获得了长度分别为1830bp和1630bp的序列。结合GenBank中已发表的韩国产中华鳖mtDNA的CR区序列,比较了3个产地中华鳖的CR区结构。分析显示:中华鳖不同产地mtDNA CR区DNA中的A+T含量分别为60.5%、63.6%和64.8%,它们的5′、3′末端以及CSB1-CSB2之间均存在丰富的可变数目串联重复序列(variable numbers oftandem repeats,VNTR)。基于mtDNA CR区序列和结构分析,显示中华鳖不同产地的野生个体中存在丰富的遗传多样性。  相似文献   

11.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

12.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

13.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

14.
15.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

16.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

17.
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.  相似文献   

18.
19.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

20.
A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/antifungal against two or more species as compared to the uncomplexed Schiff-base ligands.  相似文献   

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