Evolutionary biology of Wolbachia, selfish bacterial symbionts in insects : natural history of cytoplasmic incompatibility in a planthopper and sex ratio distortion in moths.

为了研究沃尔巴克氏体感染的时空动态，于1997-1999年在本州采集了纹状老年虫个体。ftsZ基因PCR检测表明，纹状乳杆菌种群只感染了沃尔巴克氏体B支。基于同工酶多态性分析，推测纹状体L. striatellus的远距离迁移水平并不高，不足以阻止地理居群间的遗传分化。讨论了纹状乳杆菌长距离迁移与沃尔巴克氏体感染波传播的关系。从动物地理的角度探讨了沃尔巴克氏体感染在宿主昆虫中传播与线粒体DNA变异和生殖隔离的关系。在每个玉米螟种群和肩胛骨玉米螟种群中均获得了表达生殖性状的多个母系。沃尔巴克氏体感染与遗传雄性雌性化密切相关，因此沃尔巴克氏体感染被认为是导致两种Ostrinia雌性化的原因。利用ftsZ基因的DNA序列，估计了感染Ostrinia的沃尔巴克氏体在主要沃尔巴克氏体菌株中的系统发育位置。沃尔巴克氏体感染在两种玉米螟中的流行率均较低，实验室垂直传播率较高。肩胛骨棘球蚴的5个母系虽然与沃尔巴克氏体感染无关（uSR系），但均表现出丝状发育。抗生素处理和PCR分析表明，尽管细胞质/W染色体因子(s)诱导了5个uSR谱系的分化，但每个谱系的分化都不是细菌诱导的。在每一个uSR谱系中，发生被认为具有一些机制，而不是任何已知的鳞翅目的机制。

Laodelphax striatellus individuals were sampled during 1997-1999 from Honshu in order to examine the spatio-temporal dynamics in the prevalences of Wolbachia infection. PCR assay with ftsZ gene indicated that L. striatellus populations were infected with the B clade of Wolbachia only. Based on the analysis of allozyme polymorphism, it was inferred that the level of long distance migration in L. striatellus is not as high as to prevent genetic differentiation among geographical populations. The long distance migration was discussed in relation to the advance of Wolbachia infection wave in L. striatellus. The relationships between spread of Wolbachia infection and each of mitochondrial DNA variation and reproductive isolation in host insects were discussed under the zoogeographical context.Multiple, maternal lineages expressing thelygeny trait were obtained from each of Ostrinia furnacalis and O. scapulalis populations. Wolbachia infection and feminization of genetic males were strongly associated, and therefore Wolbachia infection was considered to cause feminization in both Ostrinia species. The phylogenetic position of the Wolbachia infected with Ostrinia among major strains of Wolbachia was estimated using DNA sequences of the ftsZ gene. Wolbachia infection showed low prevalences in each of the two Ostrinia species, and high rates of vertical transmission in the laboratory. Five maternal lineages of O. scapulalis showed thelygeny although they were not associated with Wolbachia infection (uSR lineages). Antibiotic treatements and PCR assays indicated that thelygeny in each of the five uSR lineages was not bacterially induced, although was induced by a cytoplasmic/W chromosomal factor(s). The thelygeny in each of the uSR lineages was considered to be underlied with some mechanism(s) other than any of those already known from Lepidoptera.