线纹舌鳎(Cynoglossus lineolatus)18S rRNA基因长片段复制:不等交换模型(unequal crossing over model)罕见的分子证据     

龚理  时伟  杨敏  司李真  孔晓瑜 《海洋学报(英文版)》2016,35(12):38-50

尽管18S rRNA基因序列极其保守,但是在一些种类中仍然发现其存在序列多态性。本研究在线纹舌鳎18S rRNA基因中发现了3种差异显著的序列类型（Type A,B和C）,说明其为非协同进化,而不是严格遵循协同进化方式。基于以上三种类型序列GC含量、二级结构、最小自由能等差异,我们推测Type A和B可能是假基因类型。此外,在Type A类型中还发现了一段长达189 bp的重复序列。据我们所知,如此长的重复序列,这在硬骨鱼类核糖体基因中还是首次报道。通过比较分析产生重复序列常见的模型,我们认为不等交换模型最有可能解释该重复序列的形成。本研究结果不仅为不等交换模型提供了罕见的分子证据,而且为鱼类18S rRNA基因研究奠定了很好的基础。  相似文献   

Phylogeny of Saccharina and Laminaria (Laminariaceae,Laminariales, Phaeophyta) in sequence-tagged-site markers     

曲洁琼  张静  王绪敏  池姗  刘翠  刘涛 《中国海洋湖沼学报》2014,32(1):22-33

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EST-derived SNP discovery and selective pressure analysis in Pacific white shrimp (Litopenaeus vannamei)     

柳承璋  王霞  相建海  李富花 《中国海洋湖沼学报》2012,30(5):713-723

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Identification of two major histocompatibility (MH) class II A genes and their association to Vibrio anguillarum infection in half-smooth tongue sole (Cynoglossus semilaevis)     

Chunmei Li  Xubo Wang  Quanqi Zhang  Zhigang Wang  Jie Qi  Qilin Yi  Zhipeng Liu  Yanan Wang  Haiyang Yu 《中国海洋大学学报(英文版)》2012,11(1):32-44

Major histocompatibility complex class II antigens are important in vertebrate immune system.In the present study,the full cDNA sequence of class II A gene was synthesized by RACE-PCR from half-smooth tongue sole(Cynoglossus semilaevis),and its open reading frame(ORF) polymorphism was studied.The whole cDNA sequence was 992 bp in length,including the ORF with 717 bp.Twenty-five alleles were identified and clustered into two distinct groups according to the specific nucleotides/amino acids in specific positions.Eleven alleles belonged to Cyse-DAA while fourteen alleles belonged to Cyse-DBA.Four Cyse-DAA alleles were observed in one individual,and three to five Cyse-DBA alleles were observed in each of the three detected individuals,which indicated that at least two loci existed in each gene.Moreover,in order to study the function of the alleles in resistance to infection,200 individuals were intraperitoneally injected with Vibrio anguillarum and the first 20 dead individuals and 20 surviving ones were selected for genotype analysis.Fifty-six alleles were identified among the 40 individuals.Twenty-nine alleles belonged to Cyse-DAA and the other 27 alleles belonged to Cyse-DBA.Eighteen alleles were selected for studying their function in resistance to infection.Alleles Cyse-DAA*0201,Cyse-DAA*1101,Cyse-DBA*0401,Cyse-DBA*1102,Cyse-DBA*1801 and Cyse-DBA*2201 were identi-fied only in surviving individuals,while alleles Cyse-DAA*0901,Cyse-DBA*1101 and Cyse-DBA*1401 occurred more frequently in dead individuals.This study confirmed the existence and polymorphism of two class II A genes as well as the relationship between alleles of class II A genes and disease susceptibility/resistance in half-smooth tongue sole.  相似文献   

Identification of two Major Histocompatibility（MH） Class Ⅱ A Genes and Their Association to Vibrio anguillarum Infection in Half-smooth Tongue Sole（Cynoglossus semilaevis）     

LI Chunmei  WANG Xubo  ZHANG Quanqi  WANG Zhigang  QI Jie  YI Qilin  LIU Zhipeng  WANG Yanan  YU Haiyang 《青岛海洋大学学报(英文版)》2012,(1):32-44

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Application of restriction site amplified polymorphism (RSAP) to genetic diversity in Saccharina japonica     

赵翠  刘翠  李威  池姗  冯荣芳  刘涛 《中国海洋湖沼学报》2013,31(4):830-834

Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei’s genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.  相似文献   

Additions to the echinoid fauna of New Zealand     

D. G. McKnight 《新西兰海洋与淡水研究杂志》2013,47(1):90-110

Seven species of echinoids are added to the New Zealand fauna, two being described as new species of the genera Caenopedina and Spatangus Described species, new to the fauna, are Gracilechinus multidentatus (H. L. Clark), Pourtalesia laguncula A. Agassiz, Hemiaster expergitus gibbosus A. Agassiz, and Gymnopatagus magnus A. Agassiz and H. L. Clark. Fragments of Spatangus, possibly hybrid S. thor Fell, and fragments of Echinocardium, almost certainly not E. cordatum (Pennant), are also described.  相似文献   

辉石13.5A多形体的高分辨电镜研究     

王岩国  黄婉康 《岩石矿物学杂志》1992,11(3):239-242

利用高分辨电子显微术观察了球粒陨石中的顽火辉石和斜长岩中的紫苏辉石,发现沿a轴方向有周期为13.5?和22.5?两种多形体与单斜辉石及斜方辉石紧密连生。这些新多形体的产生与高温相向低温相转变过程中Si—O链的错排有关。利用高分辨像推测了Si—O链在两种多形体中的排列方式。同时,还观察和讨论了新多形结构向单斜和斜方辉石的转变。  相似文献   

Changes in bacterial community composition along a solar radiation gradient in humic waters     

Silke Langenheder  Sebastian Sobek  Lars J. Tranvik 《Aquatic Sciences - Research Across Boundaries》2006,68(4):415-424

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翘嘴鳜(Siniperca chuatsi)转录组EST-SSR位点的信息分析及其多态性检测   总被引：1，自引：1，他引：0  

袁文成  黄鹤忠  李文龙  路瑶  张茂友  王荣泉 《海洋与湖沼》2015,46(2):403-409

本研究采用高通量测序技术进行了翘嘴鳜(Siniperca chuatsi)转录组学研究,并扩增分析了EST-SSR分子标记的多态性,以期保护翘嘴鳜种质资源及良种选育,发掘其功能性SSR分子标记。结果表明,在翘嘴鳜转录组测序得到的51245条unigenes中共检测出14094个EST-SSR位点,分布于35285条Unigenes中,出现频率为27.51%。翘嘴鳜转录组EST-SSR位点的序列总长度达到195086bp,EST-SSR位点长度分布从10—25个碱基不等,平均长度13bp;翘嘴鳜转录组EST-SSR位点共有90种重复基元;其中,二核苷酸和三核苷酸重复单元是主导类型,分别占总SSR的30.62%和14.23%,且GT/AC、AAG/CCT分别占总SSR的32.12%和6.36%。随机选取100对经济性状相关EST-SSR引物的扩增产物中有24.7%表现为多态性,可作为功能性SSR分子标记开发。  相似文献