Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, The University of Leeds, Leeds LS2 9JT, UK.
Parasitology. 2009 Dec;136(14):1901-14. doi: 10.1017/S0031182009991818.
The phylum Microspora is ancient and diverse and affects a wide range of hosts. There is unusually high use of vertical transmission and this has significant consequences for transmission and pathogenicity. Vertical transmission is associated with low pathogenesis but nevertheless can have significant impact through associated traits such as sex ratio distortion. The majority of microsporidia have mixed transmission cycles and it is not clear whether they are able to modify their phenotype according to environmental circumstances. There is a great need to understand the mechanisms controlling transmission and one of the first challenges for the genomics era is to find genes associated with life cycle stages. Similarly we cannot currently predict the ease with which these parasites might switch between host groups. Phylogenetic analysis suggests that there are strong relationships between Microsporidia and their hosts. However closer typing of parasite isolates, in relation to host range and disease phenotype, is required to assess future environmental risk from these pathogens.
微孢子门是古老而多样的，影响着广泛的宿主。垂直传播的使用率非常高，这对传播和致病性有重大影响。垂直传播与低致病性相关，但通过相关特征（如性别比例扭曲）仍可能产生重大影响。大多数微孢子虫具有混合传播周期，目前尚不清楚它们是否能够根据环境情况改变其表型。我们非常需要了解控制传播的机制，而基因组时代的首要挑战之一是找到与生命周期阶段相关的基因。同样，我们目前也无法预测这些寄生虫在宿主群体之间切换的难易程度。系统发育分析表明，微孢子虫与其宿主之间存在很强的关系。然而，需要对寄生虫分离株进行更密切的分型，以评估这些病原体对未来环境风险。
