Population genetic data of a model symbiotic cnidarian system reveal remarkable symbiotic specificity and vectored introductions across ocean basins

The Aiptasia-Symbiodinium symbiosis is a promising model for experimental studies of cnidarian-dinoflagellate associations, yet relatively little is known regarding the genetic diversity of either symbiotic partner. To address this we collected Aiptasia from 17 localities throughout the world and examined the genetic diversity of both anemones and their endosymbionts. Based on newly-developed SCAR markers, Aiptasia consisted of two genetically-distinct populations, one Aiptasia lineage from Florida and a second network of Aiptasia genotypes found at other localities. These populations did not conform to the distributions of described Aiptasia species, suggesting that taxonomic re-evaluation is needed in light of molecular genetics. Associations with Symbiodinium further demonstrated the distinctions among Aiptasia populations. According to 18S-RFLP, ITS2-DGGE, and microsatellite flanker region sequencing, Florida anemones engaged in diverse symbioses predominantly with members of Symbio...

Aiptasia-虫黄藻（Symbiodinium）共生体系是研究刺胞动物-双鞭毛虫共生关系的极具潜力的实验模型，但目前对这两类共生伙伴各自的遗传多样性仍知之甚少。为填补这一研究空白，本研究从全球17个采样点采集了Aiptasia海葵，并对海葵及其内共生体的遗传多样性展开分析。基于新开发的SCAR标记（Sequence Characterized Amplified Region），研究发现Aiptasia海葵可分为两个遗传分化显著的类群：一类为来自佛罗里达州的Aiptasia谱系，另一类为在其余采样点检出的Aiptasia基因型类群。这两个类群的分布与已报道的Aiptasia物种分布并不相符，提示需结合分子遗传学手段对其分类学地位进行重新评估。与虫黄藻的共生关系分析进一步佐证了Aiptasia海葵不同类群间的差异。依据18S核糖体RNA限制性片段长度多态性（18S-RFLP）、ITS2变性梯度凝胶电泳（ITS2-DGGE）及微卫星侧翼区测序结果，佛罗里达州的海葵形成了以Symbio... 为主要共生成员的多样共生体系。