EVOLUTIONARY AND CELLH BIOLOGICAL STUDIES ON Wolbachia, ENDOCELLULAR SYMBIOTIC MICROORGANISMS

沃尔巴克氏体是一组在许多节肢动物中发现的遗传性立克次体样细菌，已知其引起宿主的各种生殖改变，包括雌性化、孤雌生殖和细胞质不相容性。我们研究了沃尔巴克氏体感染的三种蛾属于亚科Phycitinae，印度粉蛾Plodia interpunctella，杏仁蛾Ephestia cautella和地中海面粉蛾Ephestia kuehniella。我们在E. cautella和两株E. kuehniella，一个来自土浦市，另一个来自横滨市。未检测到Wolbachia在P.interpunctella。利用E. cautella和E.基于编码沃尔巴克氏体细胞表面蛋白的wsp基因的序列来估计kuehniella。我们还进行了杂交实验，以检查细胞质的不相容性。结果表明，E.卡氏杆菌引起完全的细胞质不亲和性：在感染的雄性和未感染的雌性之间的杂交中没有观察到卵孵化。土浦株和横滨株E. kuehniella表现出部分细胞质不亲和性，但两个菌株之间的水平存在显著差异。土浦株系与横滨株系间不亲和杂交的卵孵化率分别为60.8%和16.9%。

Wolbachia are a group of inherited Rickettia-like bacteria found in a number of arthropods and known to cause various reproductive alterations of their hosts, including feminization, parthenogenesis and cytoplasmic incompatibility. We examined Wolbachia infection in three species of moths belonging to the sub-family Phycitinae, the Indian meal moth Plodia interpunctella, the almond moth Ephestia cautella and the Mediterranean flour moth Ephestia kuehniella. We detected infections in E. cautella and two strains of E. kuehniella, one from Tsuchiura city and the other from Yokohama city. Wolbachia was not detected in P. interpunctella. The phylogenetic positions of Wolbachia harbored by E. cautella and E. kuehniella were estimated based on the sequences of the wsp gene that encodes a Wolbachia cell surface protein. We also performed crossing experiments to examine cytoplasmic incompatibility. It was shown that Wolbachia in E. cautella caused complete cytoplasmic incompatibility : no egg-hatch was observed in the cross between infected males and uninfected females. Both Tsuchiura and Yokohama strains of E. kuehniella showed partial cytoplasmic incompatibility, but the levels were significantly different between the two strains. The rates of egg hatch in the incompatible crosses within Tsuchiura and Yokohama strains were 60.8% and 16.9%, respectively.