Dalíková Martina, Zrzavá Magda, Hladová Irena, Nguyen Petr, Šonský Ivan, Flegrová Martina, Kubícková Svatava, Voleníková Anna, Kawahara Akito Y, Peters Ralph S, Marec František
Biology Centre CAS, Institute of Entomology, České Budějovice, Czech Republic.
Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic.
J Hered. 2017 Oct 30;108(7):709-719. doi: 10.1093/jhered/esx063.
Moths and butterflies (Lepidoptera) represent the most diverse group of animals with heterogametic females. Although the vast majority of species has a WZ/ZZ (female/male) sex chromosome system, it is generally accepted that the ancestral system was Z/ZZ and the W chromosome has evolved in a common ancestor of Tischeriidae and Ditrysia. However, the lack of data on sex chromosomes in lower Lepidoptera has prevented a formal test of this hypothesis. Here, we performed a detailed analysis of sex chromosomes in Tischeria ekebladella (Tischeriidae) and 3 species representing lower Ditrysia, Cameraria ohridella (Gracillariidae), Plutella xylostella (Plutellidae), and Tineola bisselliella (Tineidae). Using comparative genomic hybridization we show that the first 3 species have well-differentiated W chromosomes, which vary considerably in their molecular composition, whereas T. bisselliella has no W chromosome. Furthermore, our results suggest the presence of neo-sex chromosomes in C. ohridella. For Z chromosomes, we selected 5 genes evenly distributed along the Z chromosome in ditrysian model species and tested their Z-linkage using qPCR. The tested genes (Henna, laminin A, Paramyosin, Tyrosine hydroxylase, and 6-Phosphogluconate dehydrogenase) proved to be Z-linked in all species examined. The conserved synteny of the Z chromosome across Tischeriidae and Ditrysia, along with the W chromosome absence in the lower ditrysian families Psychidae and Tineidae, suggests a possible independent origin of the W chromosomes in these 2 lineages.
蛾类和蝴蝶（鳞翅目）是具有异配雌性的动物中最多样化的类群。尽管绝大多数物种具有WZ/ZZ（雌性/雄性）性染色体系统，但人们普遍认为其祖先系统是Z/ZZ，而W染色体是在巢蛾科和双孔亚目的共同祖先中进化而来的。然而，低等鳞翅目性染色体数据的缺乏阻碍了对这一假说的正式检验。在此，我们对巢蛾（巢蛾科）以及代表低等双孔亚目的3个物种——奥氏巢蛾（细蛾科）、小菜蛾（菜蛾科）和衣蛾（麦蛾科）的性染色体进行了详细分析。通过比较基因组杂交，我们发现前3个物种具有分化良好的W染色体，其分子组成差异很大，而衣蛾没有W染色体。此外，我们的结果表明奥氏巢蛾存在新性染色体。对于Z染色体，我们在双孔亚目的模式物种中选择了5个沿Z染色体均匀分布的基因，并使用定量PCR测试它们的Z连锁情况。所测试的基因（海娜、层粘连蛋白A、副肌球蛋白、酪氨酸羟化酶和6-磷酸葡萄糖酸脱氢酶）在所有检测物种中均被证明是Z连锁的。巢蛾科和双孔亚目Z染色体的保守同线性，以及低等双孔亚目家庭蓑蛾科和麦蛾科中W染色体的缺失，表明这两个谱系中W染色体可能有独立的起源。
