DNA fingerprinting reveals extensive genetic diversity in a field population of the centric diatom Ditylum brightwellii
DNA fingerprinting reveals extensive genetic diversity in a field population of the centric diatom Ditylum brightwellii
复制标题
DOI：
10.4319/lo.2000.45.6.1329
复制
发表时间：
2000-09-01
影响因子：
4.5
通讯作者：
Armbrust, EV
中科院分区：
文献类型：
--
作者：
Rynearson, TA;Armbrust, EV
利用微卫星标记技术研究了中心硅藻Ditylum brightwellii野外种群的遗传多样性。聚合酶链反应扩增的两个二核苷酸微卫星位点，从单细胞分离物提取的DNA是足够敏感的，以确定遗传上不同的克隆。四个培养物收集分离株中的每一个在遗传上是不同的。此外，从华盛顿普吉特湾的胡德运河盆地获得的24个分离株中有23个显示出独特的基因型。基因多样性为0.88，表明D. Brightwellii种群主要由无关个体组成。最大的增长率进行了测量，保持在三个光强度的8个遗传不同的领域分离。菌株的生长速率差异显着，表明高水平的生理变异也存在于人口。这项研究的结果表明，广泛的遗传和生理多样性可以存在于硅藻种群从一个单一的地理位置在一个单一的时间。假设观察到的高水平的多样性是由于暴露于不断变化的环境，从而改变选择压力的个别硅藻细胞。这里记录的广泛的生理和遗传多样性可能有助于解释硅藻如何能够在广泛的环境条件下开花。
Microsatellite markers were developed to examine the genetic diversity of field populations of the centric diatom Ditylum brightwellii. Polymerase chain reaction amplification of two dinucleotide microsatellite loci using DNA extracted from single cell isolates was sensitive enough to identify genetically distinct clones. Each of four culture collection isolates was genetically distinct. Moreover, 23 of 24 isolates obtained from the Hood Canal Basin in Puget Sound, Washington, displayed unique genotypes. The gene diversity of the field isolates is 0.88, indicating that the D. brightwellii population was composed predominantly of unrelated individuals. Maximum growth rates were measured for eight genetically distinct field isolates that were maintained at three light intensities. The growth rates of the isolates differed significantly, indicating that high levels of physiological variability also existed within the population. The results of this study indicate that both extensive genetic and physiological diversity can exist within diatom populations isolated from a single geographical locale at a single time. The observed high levels of diversity are hypothesized to result from the exposure of individual diatom cells to a constantly changing environment and thus to changing selection pressures. The extensive physiological and genetic diversity documented here may help explain how diatoms are able to bloom under a wide range of environmental conditions.