Biology Centre, Institute of Parasitology, Czech Academy of Sciences, and Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic.
Adv Parasitol. 2013;82:253-319. doi: 10.1016/B978-0-12-407706-5.00004-6.
Parasitism, aptly defined as one of the 'living-together' strategies (Trager, 1986), presents a dynamic system in which the parasite and its host are under evolutionary pressure to evolve new and specific adaptations, thus enabling the coexistence of the two closely interacting partners. Microsporidia are very frequently encountered obligatory intracellular protistan parasites that can infect both animals and some protists and are a consummate example of various aspects of the 'living-together' strategy. Microsporidia, relatives of fungi in the superkingdom Opisthokonta, belong to the relatively small group of parasites for which the host cell cytoplasm is the site of both reproduction and maturation. The structural and physiological reduction of their vegetative stage, together with the manipulation of host cell physiology, enables microsporidia to live in the cytosolic environment for most of their life cycle in a way resembling endocytobionts. The ability to form structurally complex spores and the invention and assembly of a unique injection mechanism enable microsporidia to disperse within host tissues and between host organisms, resulting in long-lasting infections. Microsporidia have adapted their genomes to the intracellular way of life, evolved strategies how to obtain nutrients directly from the host and how to manipulate not only the infected cells, but also the hosts themselves. The enormous variability of host organisms and their tissues provide microsporidian parasites a virtually limitless terrain for diversification and ecological expansion. This review attempts to present a general overview of microsporidia, emphasising some less known and/or more recently discovered facets of their biology.
寄生虫，恰当地定义为“共生”策略之一（Trager，1986），呈现出一个动态系统，其中寄生虫和宿主都受到进化压力的影响，以进化出新的和特定的适应，从而使这两个密切相互作用的伙伴得以共存。微孢子虫是非常常见的强制性细胞内原生动物寄生虫，可以感染动物和一些原生动物，是“共生”策略各个方面的一个完美示例。微孢子虫与真菌的超界 Opisthokonta 有关，属于寄生虫的相对较小的群体，其宿主细胞质是繁殖和成熟的场所。它们营养阶段的结构和生理简化，以及对宿主细胞生理学的操纵，使微孢子虫能够在其生命周期的大部分时间内以类似于内共生体的方式在胞质环境中生存。形成结构复杂孢子的能力和独特注射机制的发明和组装，使微孢子虫能够在宿主组织和宿主生物之间分散，导致持久感染。微孢子虫已经适应了它们的基因组以适应细胞内的生活方式，进化出了直接从宿主获取营养的策略，以及不仅操纵感染细胞，而且还操纵宿主自身的策略。宿主生物和组织的巨大变异性为微孢子虫寄生虫的多样化和生态扩张提供了几乎无限的领域。本文试图对微孢子虫进行概述，强调其生物学中一些不太为人知和/或最近发现的方面。
