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伴随着遗传学的发展，遗传标记经历了形态学标记、细胞学标记、生化标记和DNA分子标记4个阶段。DNA分子标记诞生于20世纪80年代中期，与其他遗传标记相比，它具有如下优点：（1）直接以DNA的形式表现，在生物各个组织、各个发育阶段都可以检测到，不受季节、环境限制；（2）数量极多，遍及整个基因组；（3）多态性高，自然存在许多等位变异；（4）表现“中性”，既不影响目标性状的表达，与不良性状也没有必然的连锁； 相似文献
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遗传标记经历了形态标记、细胞学标记、蛋白质标记及DNA标记的四个重要发展历程。纵观遗传学的发展历史,遗传学的发展推动了新型遗传标记的发展,每一种新型遗传标记的发现,均推进了遗传理论与技术的发展。19世纪后期,孟德尔以豌豆为材料,利用7对形态学标记对杂种后代的不同个体依据性状表现进行归类分析,发现了著名的遗传分离规律和独立分配规律。细胞学标记是指能明确显示遗传多态性的细胞学特征,如染色体形态、数目和结构在不同物种中的差异等,可以作为一种遗传标记来进行基因定位。20世纪50年代,人们发现同工酶是一种可用于物种起源与进化研究、种质鉴定、分类等诸多领域的分子标记技术(Markert et al.,1959)20世纪后期以来,DNA分子标记技术不断涌现,相继建立了RFLP(restriction fragment lengthen polymorphisis)、DNA指纹 (DNA fingerprint)，RAPD (random anplified polymophism DNA), AFLP(amplified fragnent lengthen polynorphisn)、微卫星 DNA (microsate llite DNA).SNP(single nucleotide polymorphisn)等专门的技术，在生物研究中得以广泛应用。分子标记技术应用于藻类学研究较晚,主要用于藻类的系统发生、地理分布、种群遗传、分类、亲本鉴定、杂种优势的鉴别及种质鉴定等领域。 相似文献
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微卫星DNA标记技术及其在海洋生物遗传学中的应用 总被引：3，自引：0，他引：3
DNA简单重复序列从1974年在海洋生物中被发现,到1989年“微卫星”术语开始使用这段时间是这种新型分子标记技术的发展阶段。伴随着PCR技术的发明、成熟与拓展,微卫星DNA以其多态性高、随机分布、共显性遗传、重复性好等特点在生物学的个体及系统发育方面得到很广泛的应用。本文从微卫星DNA的发展简史开始,较详细地介绍了它的原理、方法及策略,然后概括了在海洋动、植物的遗传学中,微卫星DNA在遗传多样性分析、遗传图谱构建、基因鉴定和标记以及系谱认证等领域的研究,展望了其在海洋生物分子育种、基因克隆、生物保护等方面的应用前景。 相似文献
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繁殖方式是生物重要生物学特征之一。了解生物繁殖方式对遗传和育种研究具有重要意义。赫氏球石藻(Emiliania huxleyi)呈世界性分布,在生态系统中扮演重要角色,但其繁殖方式未知。本研究用分子系统学方法确定有基因组序列且行有性生殖的真核生物的减数分裂相关基因数量,建立了"减数分裂相关基因≥19个,其中减数分裂特异基因≥5个"的有性生殖判别标准;发现赫氏球石藻具有25个减数分裂相关基因,包括6个减数分裂特异基因。依据建立的标准判定赫氏球石藻行有性生殖。研究结果将有助于赫氏球石藻生活史和遗传学研究。 相似文献
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蟹类线粒体DNA的研究与应用 总被引：7，自引：1，他引：7
徐敬明 《中国海洋大学学报(自然科学版)》2006,36(6):879-884
线粒体DNA作为理想的分子遗传标记已被广泛用于蟹类种群遗传学和进化遗传学的研究,并取得了许多有意义的结果。本文阐述了蟹类线粒体DNA分子生物学的研究进展,重点介绍蟹类线粒体DNA序列的研究概况及其多态性在蟹类系统学、种群识别、起源和进化、地理分化等研究中的应用情况。 相似文献
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分子标记概述及其在藻类中的应用 总被引：1，自引：0，他引：1
遗传标记经历了形态标记、细胞学标记、蛋白质标记及DNA标记的四个重要发展历程。纵观遗传学的发展历史,遗传学的发展推动了新型遗传标记的发展,每一种新型遗传标记的发现,均推进了遗传理论与技术的发展。19世纪后期,孟德尔以豌豆为材料,利用7对形态学标记对杂种后代的不同个体依据性状表现进行归类分析,发现了著名的遗传分离规律和独立分配规律。细胞学标记是指能明确显示遗传多态性的细胞学特征,如染色体形态、数目和结构在不同物种中的差异等,可以作为一种遗传标记来进行基因定位。20世纪50年代,人们发现同工酶是一种可用于物种起源与… 相似文献
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摘 分子遗传标记是随着分子生物学技术的发展而出现的遗传标记技术，它突破了形态和细胞水平上遗传标记的局限性，发挥着独特的优势。本文简要介绍了同工酶、RFLP、RAPD、AFLP、mtDNA、SSR等几种常用的分子遗传标记技术方法，并比较了各种技术的优点和局限性；概述了这些遗传标记技术在海洋经济贝类群体遗传结构和变异、遗传分化、遗传育种、种质鉴定、基因定位和构建遗传图谱研究等方面的应用和取得的研究成果。 相似文献
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利用PCR技术对澄黄滨珊瑚的2种分子标记（线粒体细胞色素氧化酶亚基1基因COI和核糖体RNA内转录间隔区基因ITS）进行测序,探讨COI序列和ITS序列在澄黄滨珊瑚（Porites lutea）群体研究中的适用性,并从中选出最适合研究澄黄滨珊瑚群体遗传多样性的分子标记．结果显示COI序列变异位点少,成对序列差异在群体内、群体间都很小,不适于澄黄滨珊瑚的群体研究;而ITS区序列个体内成对的序列差异仅为0．35％,可以作为研究澄黄滨珊瑚群体遗传多样性的分子标记;通过对ITS1、ITS2、5．8SrRNA、ITS1＋ITS2及ITS区序列的比较,认为ITS1＋ITS2序列是最适合研究澄黄滨珊瑚群体遗传多样性的分子标记．本研究为以后研究我国沿岸造礁石珊瑚澄黄滨珊瑚的群体遗传结构提供方法依据,从而为保护管理扣恢复受损珊瑚礁生态系统提供遗传学数据支持． 相似文献
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Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China 总被引：1，自引：1，他引：0
L&#; E ZHANG Lei CHEN Min QIU Yusheng XING N YANG Weifeng LI Yanping HUANG Yipu 《海洋学报(英文版)》2008,27(1):29-41
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium （ 〈 0.4 μm） exis- ted in the low molecular mass fraction （ 〈 10 000 u）, and the colloidal uranium-238 （10 000 u -0.4 μm） only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases （ 〉 0.4 μm）, the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows： 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows ： 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value （1.0）. The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic 相似文献
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JIN Xianglong 《海洋学报(英文版)》2013,32(12):1-3
In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future. 相似文献
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湄洲湾夏季的初级生产力 总被引：2，自引：3，他引：2
湄洲湾１９９２年夏季的叶绿素ａ，三磷酸腺苷，碳比积累速率，初级生产力的变化范围和均值分别为０．４５－４．７２，１．４９ｍｇ／ｍ＾３；０．１２－１．０７，０．３１μｇ／ｄｍ＾３；０．０６－０．５８，０．３４ｄ＾－１；０．０７－０．３４，０．２１ｍ／（ｍ＾２．ｄ）。叶绿素ａ与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素ａ三磷本能腺苷的比值为４．８，湄洲湾夏季浮游植物的生长受氮不足 相似文献
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In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (Kd) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate. 相似文献
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中国科学院海洋研究所建所70年来，在海洋贝类分类学研究领域取得了长足发展与进步，做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展，概述了取得的主要科研成果，分析了现代腹足类分类学研究的发展趋势以及面临的挑战，并对今后的发展提出了相应对策和建议。 相似文献
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《Deep Sea Research Part I: Oceanographic Research Papers》1999,46(8):1391-1415
The biomass, species and chemical composition of the mesozooplankton and their impact on lower food levels were estimated along a transect across the Arctic Ocean. Mesozooplankton biomass in the upper 200 m of the water column was significantly higher (19–42 mg DW m-3) than has previously been reported for the Arctic Ocean, and it reached a maximum at ca. 87°N in the Amundsen Basin. The lowest values were recorded in the Chukchi Sea and Nansen Basin, where ice cover was lower (50–80%) than in the central Arctic Ocean. In the deeper strata (200–500 m) of the Canadian and Eurasian Basins, the biomass was always much lower (4.35–16.44 mg DW m-3). The C/N (g/g) ratio for the mesozooplankton population was high (6.5–8.5) but within the documented range. These high values (when compared to 4.5 at lower latitudes) may be explained by the high lipid content. Mesozooplankton accounted for approximately 40% of the total particulate organic carbon in the upper 100 m of the water column. Mesozooplankton species composition was homogeneous along the transect, consisting mainly of copepods (70–90% of the total number). It was dominated by four large copepod species (Calanus hyperboreus, C. glacialis, C. finmarchicus and Metridia longa), which together accounted for more than 80% of the total biomass. According to measurements of gut pigment and gut turnover rates, the mesozooplankton on average ingested between 6 and 30% of their body carbon per day as phytoplankton. Microzooplankton may have provided an additional source of energy for the mesozooplankton community. These data emphasize the importance of mesozooplankton in the arctic food web and reinforce the idea that the Arctic Ocean should no longer be considered to be a “biological desert”. 相似文献
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