Analysis of the distribution and population composition dynamics of red tide-causing microalgae based on their genomic polymorphism

本研究的目的是建立遗传标记来鉴定一种引起种内赤潮异弯藻的赤潮细菌。采用随机扩增多态性DNA(RAPD)技术检测赤潮隐翅虫不同菌株间的基因组多态性。根据扩增产物序列设计的一些序列标签位点(STS)引物，通过聚合酶链式反应(PCR)扩增，特异性地检测到赤潮杆菌。微卫星引物聚合酶链式反应检测到赤潮隐翅虫的基因组多态。部分针对扩增子中发现的微卫星的STS引物通过聚合酶链式反应(PCR)特异性检测到赤潮梭菌。测定了赤潮沙门菌和赤潮沙门菌的16S rDNA和rbcL之间以及赤潮沙门氏菌质潮DNA上的rbcL和cfxQ之间的核苷酸序列。Chattonella种在rbcL和rbcS之间的基因间隔区没有序列差异。在近海海水中加入赤潮细胞，建立赤潮模型，制备环境DNA。建立了一些遗传标记，建立在赤潮DNA(签名A-E，Akase等)上。等人，2004年)从环境DNA中检测到赤潮杆菌菌株，表明这些标记可用于海洋自然环境中赤潮杆菌菌株或种群的种内检测。

The aim of this research is to establish genetic markers to identify a red-tide causing raphidophyte Heterosigma akashiwo intraspecifically.1. The random amplified polymorphic DNA (RAPD) technique detected genomic polymorphism among H. akashiwo strains. Some of sequence-tagged site (STS) primers designed according to the amplicon sequences detected H. akashiwo strains specifically by means of PCR amplification.2. The microsatellite-primed PCR detected genomic polymorphism among H. akashiwo strains. Some of STS primers targeting to the microsatellites found in the amplicon detected H. akashiwo strains specifically by PCR amplification.3. Nucleotide sequences between 16S rDNA and rbcL encoded on the H. akashiwo plastidal DNA, and between rbcL and cfxQ encoded on the plastidal DNA of Chattonella species, which belong to the family Raphidophyceae as well as H. akashiwo, were determined. The Chattonella species showed no sequence differences at the intergenic region between rbcL and rbcS.4. A model of red tide blooms was constructed by adding H akashiwo cells to coastal seawater, and the environmental DNA was prepared. Some of the genetic markers established on the H akashiwo plastidal DNA (Signature A-E, Akase, et. al., 2004) detected H. akashiwo strains specifically from the environmental DNA, suggesting availability of these markers for intraspecific detection of H. akashiwo strains or populations from marine natural environments.