Genetic diversity of algal and fungal partners in four species of Umbilicaria (Lichenized Ascomycetes) along a transect of the Antarctic peninsula.
Genetic diversity of algal and fungal partners in four species of Umbilicaria (Lichenized Ascomycetes) along a transect of the Antarctic peninsula.
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DOI：
10.1093/oxfordjournals.molbev.a004181
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发表时间：
2002-08
影响因子：
10.7
通讯作者：
J. Romeike;T. Friedl;Gert Helms;S. Ott
中科院分区：
文献类型：
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作者：
J. Romeike;T. Friedl;Gert Helms;S. Ott
从南极洲5,000 km的样带中采集了来自脐藻属的地衣，并对核糖体DNA核内转录间隔区480-660 bp区域的DNA序列多态性进行了研究。从真菌（16子囊菌）和光合作用的合作伙伴（22绿藻属Trebouxia）的序列进行了测定和比较，从地衣的同源物居住在更温和的大陆性气候。系统发育分析表明，南极地衣殖民他们目前的栖息地，通过多个独立的殖民活动，从温带登船区，并通过最近的远程分散在南极成功的预先存在的殖民者。此外，研究结果表明，reichenization-de novo建立的真菌光合共生nonlichenized藻类和真菌细胞-南极地衣扩散过程中发生。因此，即使在南极恶劣的条件下，藻类和真菌培养物的独立传播也能成功地建立地衣共生。
Lichens from the genus Umbilicaria were collected across a 5,000-km transect through Antarctica and investigated for DNA sequence polymorphism in a region of 480-660 bp of the nuclear internal transcribed spacer region of ribosomal DNA. Sequences from both fungal (16 ascomycetes) and photosynthetic partners (22 chlorophytes from the genus Trebouxia) were determined and compared with homologs from lichens inhabiting more temperate, continental climates. The phylogenetic analyses reveal that Antarctic lichens have colonized their current habitats both through multiple independent colonization events from temperate embarkation zones and through recent long-range dispersal in the Antarctic of successful preexisting colonizers. Furthermore, the results suggest that relichenization-de novo establishment of the fungus-photosynthesizer symbiosis from nonlichenized algal and fungal cells-has occurred during the process of Antarctic lichen dispersal. Independent dispersal of algal and fungal cultures therefore can lead to a successful establishment of the lichen symbiosis even under harsh Antarctic conditions.