Usmanova Regina R, Ataev Gennady L, Tokmakova Arina S, Tsymbalenko Nadezhda V, Prokhorova Elena E
Laboratory of Experimental Zoology, Department of Zoology and Genetics, Faculty of Biology, Herzen State Pedagogical University of Russia, 191186, Moyka river 48, St. Petersburg, Russia.
Parasitol Res. 2023 Apr;122(4):997-1007. doi: 10.1007/s00436-023-07805-7. Epub 2023 Mar 6.
The sporocysts of the trematode Leucochloridium paradoxum parasitise land snails Succinea putris. The sporocysts form broodsacs whose tegument contains green and brown pigments. The colouration changes during maturation. The pattern and colour of the broodsacs may vary in different individuals and sometimes even in one sporocyst. We studied the broodsacs of 253 sporocysts of L. paradoxum collected in the European part of Russia and Belarus, and identified four main colouration types. An analysis of genetic polymorphism by a fragment (757 bp) of the mitochondrial cox1 gene revealed 22 haplotypes. Using the nucleotide sequences of the cox1 gene fragment of L. paradoxum from Japan and Europe available in GenBank, we constructed haplotype networks. A total of 27 haplotypes were identified. The haplotype diversity of L. paradoxum by this gene was rather low, on the average 0.8320. A low genotypic diversity by the mitochondrial marker is consistent with rDNA conservativeness of Leucochloridium spp. noted previously. The most broadly represented haplotypes, Hap_1 and Нap_3, were described in both sporocysts and adults of L. paradoxum. We suggest that the mobility of birds, which are the definitive hosts of L. paradoxum, provides the necessary conditions for the genotypic diversity of its sporocysts parasitising different populations of snails Succinea putris.
奇异双盘吸虫的孢子囊寄生于陆地蜗牛腐殖琥珀螺。孢子囊形成育囊，其体表含有绿色和棕色色素。颜色在成熟过程中会发生变化。育囊的图案和颜色在不同个体中可能有所不同，有时甚至在一个孢子囊内也会不同。我们研究了在俄罗斯欧洲部分和白俄罗斯收集的253个奇异双盘吸虫孢子囊的育囊，并确定了四种主要的颜色类型。通过线粒体细胞色素c氧化酶亚基1（cox1）基因的一个片段（757 bp）进行的遗传多态性分析揭示了22个单倍型。利用GenBank中可获得的来自日本和欧洲的奇异双盘吸虫cox1基因片段的核苷酸序列，我们构建了单倍型网络。总共鉴定出27个单倍型。该基因的奇异双盘吸虫单倍型多样性相当低，平均为0.8320。线粒体标记显示的低基因型多样性与先前指出的双盘属核糖体DNA的保守性一致。最广泛出现的单倍型Hap_1和Hap_3在奇异双盘吸虫的孢子囊和成虫中均有描述。我们认为，作为奇异双盘吸虫终末宿主的鸟类的活动为其寄生于不同腐殖琥珀螺种群的孢子囊的基因型多样性提供了必要条件。
