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151.
Expression of putative zinc-finger protein lcn61 gene in lymphocystis disease virus China (LCDV-cn) genome 总被引:1,自引:0,他引:1
An open reading frame (lcn61) of lymphocystis disease virus China (LCDV-cn), probably responsible for encoding putative zinc-finger proteins was amplified
and inserted into pET24a (+) vector. Then it expressed in E. coli BL21 (DE3), and His-tag fusion protein of high yield was obtained. It was found that the fusion protein existed in E. coli mainly as inclusion bodies. The bioinformatics analysis indicates that LCN61 is C2H2 type zinc-finger protein containing
four C2H2 zinc-finger motifs. This work provides a theory for functional research of lcn61 gene.
Supported by High Technology Research and Development Program of China (863 Program, No. 2006AA100309) 相似文献
152.
利用ISSR标记对牙鲆♀与石鲽♂单对杂交亲本及其子一代(全同胞家系)的分离方式进行了研究。结果表明,8个ISSR引物共扩增出181个标记,其中116个为多态性,占总数的64.09%;标记在F1代呈三种分离方式:符合孟德尔分离比例、偏离孟德尔分离比例和异常分离。符合孟德尔分离比例的情况包括:不分离(代表了亲本基因型的5种组合:AA×AA、AA×Aa、Aa×AA、AA×aa、aa×AA);1︰1分离(代表了亲本基因型的2种组合:Aa×aa、aa×Aa);3︰1分离(代表了亲本基因型的1种组合:Aa×Aa)。偏分离的标记包括:亲本中呈多态而在子代中偏离1︰1分离的标记和亲本均有而在子代中偏离3︰1分离的标记。异常分离的标记包括:F1代出现双亲均不具备的标记和双亲或单亲有而子代却无的标记。3种分离位点出现的频率和数量分别为:82.87%、150,11.05%、20,6.08%、11;双亲共有标记中85.33%的不发生分离,单亲特有标记中28.57%—35.85%发生正常分离,该研究结果可为进一步利用该群体构建牙鲆和石鲽遗传连锁图谱奠定良好的工作基础并提供一定的理论依据。 相似文献
153.
综合运用高精度层序地层学、构造一地层学方法,认为十屋断陷深层发育的各类隐蔽圈闭是下一步勘探工作的重要目标。同时,由于构造对沉积的控制作用,在断陷内部不同的构造部位具有不同的隐蔽圈闭分布特征。十屋断陷西部皮家地区、北部张家屯一八屋地区位于油气主要运移指向区,分别由断裂坡折带和以挠曲型褶皱为特征的弯折带控制的储集砂体十分发育,盖层及保存条件也十分优越,是深部原生岩性、地层油气藏最有利的勘探目标区带。 相似文献
154.
珠江口盆地珠三坳陷层序地层样式分析 总被引:10,自引:0,他引:10
珠江口盆地珠三坳陷是一个典型的箕状断陷盆地,其层序地层格架受到主干断裂特别是珠三南断裂的强烈控制。由于珠三南断裂活动的差异性,盆地东部、中部和西部表现为不同的格架样式。并据此划分出坳陷内的3种典型层序样式,分别是缓坡型、断控陡坡型和断阶型层序样式。文昌A凹陷与阳江低凸起过渡的斜坡区和文昌B凹陷与琼海低凸起过渡区为具有坡折的缓坡背景,发育缓坡坡折型层序样式,发育斜坡扇、盆底扇、低位楔。珠三南断裂等主干断裂下降盘发育断控陡坡带层序样式,在珠三南断裂中部地区,发育断阶型层序样式。 相似文献
155.
ZHENG Lianming LIN Yuanshao LI Shaojing CAO Wenqing XU Zhenzu HUANG Jiaqi 《海洋学报(英文版)》2009,28(1):109-115
Aequorea taiwanensis, a new hydrozoan species from the Taiwan Strait was described using morphological and molecular characteristics. Both morphological and mitochondrial cytochrome oxidase subunit I (mtCOI) data supported A. taiwanensis n. sp. as a valid species. Sequence divergence and genetic distance of A. taiwanensis n. sp., A. papillata and A. conica were analysed based on the mtCOI gene sequences. The mtCOI sequences from these three species of the genus Aequorea showed high variation frequency, with sequence divergences ranging from 9.10% to 11.9%, and pairwise genetic distances ranging from 0.097 to 0.130. MtCOI sequence analysis provided diagnostic molecular systematic characteristics for accurate identification and discrimination of the species of Aequorea or their populations, and will be used to resolve evolutionary relationships among them.It was suggested that 10%—20% pairwise mtCOI sequence differences indicated the specieslevel divergence among congeneric species in the Hydromedusae. 相似文献
156.
Molecular organic biomarkers together with trace element composition were investigated in sediments east of Barrow Canyon in the western Arctic Ocean to determine sources and recycling of organic carbon in a continuum from the shelf to the basin. Algal biomarkers (polyunsaturated and short-chain saturated fatty acids, 24-methylcholesta-5,24(28)-dien-3β-ol, dinosterol) highlight the substantial contribution of organic matter from water column and sea-ice primary productivity in shelf environments, while redox markers such as acid volatile sulfide (AVS), Mn, and Re indicate intense metabolism of this material leading to sediment anoxia. Shelf sediments also receive considerable inputs from terrestrial organic carbon, with biomarker composition suggesting the presence of multiple pools of terrestrial organic matter segregated by age/lability or hydrodynamic sorting. Sedimentary metabolism was not as intense in slope sediments as on the shelf; however, sufficient labile organic matter is present to create suboxic and anoxic conditions, at least intermittently, as organic matter is focused towards the slope. Basin sediments also showed evidence for episodic delivery of labile organic carbon inputs despite the strong physical controls of water depth and sea-ice cover. Principal components analysis of the lipid biomarker data was used to estimate fractions of preserved recalcitrant (of terrestrial origin) and labile (of marine origin) organic matter in the sediments, with ranges of 12–79%, 14–45%, and 37–66% found for the shelf, slope, and basin cores, respectively. On average, the relative preserved terrestrial organic matter in basin sediments was 56%, suggesting exchange of organic carbon between nearshore and basin environments in the western Arctic. 相似文献
157.
Kensuke Iwamoto Akihiro Takemura Tetsuo Yoshino Hideyuki Imai 《Journal of Oceanography》2009,65(1):103-112
The mitochondrial DNA (mtDNA) control region was sequenced to examine the genetic variability and gene flow of juvenile Siganus spinus and S. guttatus. In total, 461 nucleotide sequences were obtained from 69 specimens of juvenile S. spinus from Okinawa Island and Ishigaki Island, in which 17 variable sites and 22 haplotypes were identified. Haplotype diversity
(h) was high (0.9244 in Okinawa and 0.8984 in Ishigaki), whereas nucleotide diversity (π) was low (0.0063 in Okinawa and 0.0059 in Ishigaki). The two populations were not genetically distinct. Siganus guttatus, which do not form large schools at recruitment, in contrast S. spinus, were also analyzed by studying 152 individuals collected off Okinawa Island, Miyako Island, and Ishigaki Island. Of 476
nucleotide sequences, 50 were variable, and 42 haplotypes were identified. Genetic variability values were high (h = 0.8766 and π = 0.0151 in Okinawa; h = 0.9640 and π = 0.0192 in Miyako; h = 0.9161 and π = 0.0199 in Ishigaki). The Okinawa population was genetically isolated from the Miyako and Ishigaki populations. As a result,
genetic diversity was high for each of these siganid populations despite their being target species for fisheries; however,
the degree of inter-population gene flow was higher for S. spinus than S. guttatus, suggesting that these species exhibit different dispersal strategies. 相似文献
158.
西湖凹陷平北地区平湖组基于地震多属性的储层预测 总被引:2,自引:0,他引:2
始新统平湖组是东海西湖凹陷平北地区最重要的油气储层,但受资料条件的限制,应用常规方法无法进行精细的储层预测,制约了研究区的油气勘探部署和进程。应用地震多属性分析技术,结合测井曲线、岩心、岩性及区域地质资料,对平北地区平湖组的岩相进行了精细解释,并对有利目标区进行了初步预测,结果表明,平北地区平湖组发育潮汐控制的三角洲相和潮坪相两种类型的沉积相,并以三角洲相内的储层发育,砂体连片性好,工区西南部三角洲前缘相发育区为油气勘探的有利目标区。 相似文献
159.
The Cuu Long Basin (Mekong Basin) is a rift basin off southern Vietnam, and the most important petroleum producing basin in the country. However, information on petroleum type and characteristics has hitherto been largely unavailable to the public. This paper presents petroleum geochemical data on nine oil samples from four different producing fields in the Cuu Long Basin: the Dragon (Rong), Black Lion (Sutu-Den), Sunrise (Rang ?ong) and White Tiger (Bach Ho) Fields. The oils are highly paraffinic with bimodal normal alkane distributions and show moderate pristane to phytane ratios and a conspicuous hyperbolic decrease in abundance with increasing carbon number of hopane homologues from C30 to C35. The TPP-index of Holba et al. (Holba, A.G., Dzou, L.I., Wood, G.D., Ellis, L., Adam, P., Schaeffer, P., Albrecht, P., Greene, T., Hughes, W.B., 2003. Application of tetracyclic polyprenoids as indicators of input from fresh–brackish water environments. Organic Geochemistry 34, 441–469) is equal to 1 in all samples which in combination with tricyclic triperpane T26/T25 ratios >1 and the n-alkane and hopane distributions mentioned above provide a strong indication of an origin from lacustrine source rocks. This is supported by the absence of marine C30 desmethyl steranes (i.e. 24-n-propylcholestanes) and marine diatom-derived norcholestanes. Based on the overall biological marker distributions, the lakes probably belonged to the overfilled or balanced-fill types defined by Bohacs et al. (Bohacs, K.M., Carroll, A.R., Neal, J.E., Mankiewicz, P.J., 2000. Lake-basin type, source potential, and hydrocarbon character. An integrated sequence-stratigraphic–geochemical framework. AAPG Studies in Geology 46, 3–34). The oils were generated from source rocks at early- to mid-oil-window maturity, presumably Oligocene lacustrine shales that are present in the syn-rift succession. Oils from individual fields may, however, be distinguished by a combination of biological marker parameters, such as the oleanane index, the gammacerane index, the relative abundance of tricyclic terpanes, the proportions of diasteranes and 28-norspergulane, complemented by other parameters. The oils of the Cuu Long Basin show an overall similarity to the B-10 oil from the Song Hong Basin off northern Vietnam, but are markedly different from the seepage oils known from Dam Thi Nai on the coast of central Vietnam. 相似文献
160.