Menezes Rodolpho S T, Bardella Vanessa B, Cabral-de-Mello Diogo C, Lucena Daercio A A, Almeida Eduardo A B
Laboratório de Biologia Comparada e Abelhas, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras (FFCLRP), Universidade de São Paulo (USP), Av. Bandeirantes, 3900, Ribeirão Preto, SP, 14040-901, Brazil.
Instituto de Biociências/IB, Departamento de Biologia, Universidade Estadual Paulista (UNESP), Av. 24A, 1515, Rio Claro, SP, 13506-900, Brazil.
Naturwissenschaften. 2017 Sep 27;104(9-10):85. doi: 10.1007/s00114-017-1507-z.
Despite the (TTAGG) telomeric repeat supposed being the ancestral DNA motif of telomeres in insects, it was repeatedly lost within some insect orders. Notably, parasitoid hymenopterans and the social wasp Metapolybia decorata (Gribodo) lack the (TTAGG) sequence, but in other representatives of Hymenoptera, this motif was noticed, such as different ant species and the honeybee. These findings raise the question of whether the insect telomeric repeat is or not phylogenetically predominant in Hymenoptera. Thus, we evaluated the occurrence of both the (TTAGG) sequence and the vertebrate telomere sequence (TTAGGG) using dot-blotting hybridization in 25 aculeate species of Hymenoptera. Our results revealed the absence of (TTAGG) sequence in all tested species, elevating the number of hymenopteran families lacking this telomeric sequence to 13 out of the 15 tested families so far. The (TTAGGG) was not observed in any tested species. Based on our data and compiled information, we suggest that the (TTAGG) sequence was putatively lost in the ancestor of Apocrita with at least two subsequent independent regains (in Formicidae and Apidae).
尽管（TTAGG）端粒重复序列被认为是昆虫端粒的祖先DNA基序，但它在一些昆虫目中多次丢失。值得注意的是，寄生性膜翅目昆虫和社会性黄蜂Metapolybia decorata（格里博多）缺乏（TTAGG）序列，但在膜翅目的其他代表物种中，如不同种类的蚂蚁和蜜蜂，发现了这个基序。这些发现引发了一个问题，即昆虫端粒重复序列在膜翅目中是否在系统发育上占主导地位。因此，我们使用斑点杂交技术评估了25种膜翅目针尾部物种中（TTAGG）序列和脊椎动物端粒序列（TTAGGG）的出现情况。我们的结果显示，在所有测试物种中均未发现（TTAGG）序列，使迄今测试的15个膜翅目科中缺乏这种端粒序列的科数增加到13个。在任何测试物种中均未观察到（TTAGGG）。基于我们的数据和汇编信息，我们认为（TTAGG）序列可能在细腰亚目祖先中丢失，随后至少有两次独立的重新获得（在蚁科和蜜蜂科中）。
