High symbiont diversity in the bone-eating worm Osedax mucofloris from shallow whale-falls in the North Atlantic
High symbiont diversity in the bone-eating worm Osedax mucofloris from shallow whale-falls in the North Atlantic
复制标题
DOI：
10.1111/j.1462-2920.2010.02299.x
复制
发表时间：
2010-08-01
影响因子：
5.1
通讯作者：
Dubilier, Nicole
中科院分区：
文献类型：
--
作者：
Verna, Caroline;Ramette, Alban;Dubilier, Nicole
奥塞达克斯蠕虫是鲸鱼坠落专家，它们的根组织渗入鲸鱼的骨头。这些充满了内共生细菌，假设它们通过从鲸鱼骨头中提取有机化合物来为宿主提供营养。采用比较16 S rRNA序列分析和荧光原位杂交（FISH）技术，研究了北大西洋浅海鲸鱼瀑布中Osedax mucofloris共生菌的多样性和分布。我们观察到更高的多样性的内共生体比以前描述的其他Osedax物种。内共生体序列分为8个遗传学上不同的簇（簇之间的相似性为91.4-98.9%），簇内观察到相当大的微多样性（99.5-99.7%的相似性）。统计检验显示，宿主个体对内共生体的多样性和分布有非常显著的影响，集群之间的变异性为68%，集群内的变异性为40%。FISH分析表明，大多数主机个人占主导地位的内共生体从一个单一的集群，与内共生体从丰富的集群一般局限于周边根组织。观察到的多样性和分布模式表明，内共生体是从环境中水平传播的，随着宿主根组织生长到鲸鱼骨骼中，会发生重复的感染事件。
P>Osedax worms are whale-fall specialists that infiltrate whale bones with their root tissues. These are filled with endosymbiotic bacteria hypothesized to provide their hosts with nutrition by extracting organic compounds from the whale bones. We investigated the diversity and distribution of symbiotic bacteria in Osedax mucofloris from shallow-water whale-falls in the North Atlantic using comparative 16S rRNA sequence analysis and fluorescence in situ hybridization (FISH). We observed a higher diversity of endosymbionts than previously described from other Osedax species. Endosymbiont sequences fell into eight phylogenetically distinct clusters (with 91.4-98.9% similarity between clusters), and considerable microdiversity within clusters (99.5-99.7% similarity) was observed. Statistical tests revealed a highly significant effect of the host individual on endosymbiont diversity and distribution, with 68% of the variability between clusters and 40% of the variability within clusters explained by this effect. FISH analyses showed that most host individuals were dominated by endosymbionts from a single cluster, with endosymbionts from less abundant clusters generally confined to peripheral root tissues. The observed diversity and distribution patterns indicate that the endosymbionts are transmitted horizontally from the environment with repeated infection events occurring as the host root tissues grow into the whale bones.