Krafsur E S
Department of Entomology, Iowa State University, Ames, IA 50011, USA.
Infect Genet Evol. 2009 Jan;9(1):124-41. doi: 10.1016/j.meegid.2008.09.010. Epub 2008 Oct 17.
Tsetse flies (Diptera: Glossinidae) are an ancient taxon of one genus, Glossina, and limited species diversity. All are exclusively haematophagous and confined to sub-Saharan Africa. The Glossina are the principal vectors of African trypanosomes Trypanosoma sp. (Kinetoplastida: Trypanosomatidae) and as such, are of great medical and economic importance. Clearly tsetse flies and trypanosomes are coadapted and evolutionary interactions between them are manifest. Numerous clonally reproducing strains of Trypanosoma sp. exist and their genetic diversities and spatial distributions are inadequately known. Here I review the breeding structures of the principle trypanosome vectors, G. morsitans s.l., G. pallidipes, G. palpalis s.l. and G. fuscipes fuscipes. All show highly structured populations among which there is surprisingly little detectable gene flow. Rather less is known of the breeding structure of T. brucei sensu lato vis à vis their vector tsetse flies but many genetically differentiated strains exist in nature. Genetic recombination in Trypanosoma via meiosis has recently been demonstrated in the laboratory thereby furnishing a mechanism of strain differentiation in addition to that of simple mutation. Spatially and genetically representative sampling of both trypanosome species and strains and their Glossina vectors is a major barrier to a comprehensive understanding of their mutual relationships.
采采蝇（双翅目：舌蝇科）是舌蝇属的一个古老分类单元，物种多样性有限。它们均为专性吸血昆虫，仅分布于撒哈拉以南非洲地区。舌蝇属是非洲锥虫（锥虫属，动质体目：锥虫科）的主要传播媒介，因此具有重大的医学和经济意义。显然，采采蝇与锥虫已经共同适应，它们之间的进化相互作用十分明显。存在许多克隆繁殖的锥虫菌株，但其遗传多样性和空间分布情况尚不清楚。在此，我综述主要锥虫传播媒介——莫氏舌蝇复合种、淡黄舌蝇、须舌蝇复合种和fuscipes fuscipes舌蝇的繁殖结构。所有这些舌蝇种群结构都高度分化，令人惊讶的是，其间几乎检测不到基因流动。相对于其传播媒介采采蝇而言，人们对布氏锥虫复合种的繁殖结构了解较少，但自然界中存在许多遗传分化的菌株。最近在实验室中已证实锥虫可通过减数分裂进行基因重组，这为除简单突变之外的菌株分化提供了一种机制。对锥虫物种和菌株及其舌蝇传播媒介进行具有空间代表性和遗传代表性的采样，是全面了解它们相互关系的一个主要障碍。
