The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi Yunnan, China.
The Key Sericultural Laboratory of Shaanxi, Ankang University, Ankang Shaanxi, China.
PLoS One. 2020 Oct 2;15(10):e0240193. doi: 10.1371/journal.pone.0240193. eCollection 2020.
Fuyin-lethal red egg (Fuyin-lre) is a red egg mutant discovered from the germplasm resource Fuyin of Bombyx mori. The embryo of Fuyin-lre stops developing at the late stage of gastrulation due to chromosome structural variation. In this work, precise mutation sites at both ends of the mutated region were determined, and two inserted sequences with lengths of 1232 bp and 1845 bp were obtained at both ends of the mutation region. Interestingly, a bmmar1 transposon was detected in the inserted 1845 bp sequence. Bmmar1 possesses features of the Tcl/mariner superfamily of transposable elements (TEs), which belongs to class II TEs that use a DNA-mediated "cut and paste" mechanism to transpose. This finding suggests that Fuyin-lre mutation might be related to the "cut and paste" action of bmmar1. The mutation resulted in the deletion of 9 genes in the mutation region, of which the red egg gene re (BMSK0002766) did not affect embryonic development of B. mori, and the BMSK0002765 gene was unexpressed during the early stage of embryonic development. The RNA interference results of the remaining 7 genes suggest that the semaphorin-1a-like gene (BMSK0002764) had a major contribution to the embryonic lethality of Fuyin-lre.
福荫致死红卵（Fuyin-lre）是从家蚕种质资源福荫中发现的一种红卵突变体。由于染色体结构变异，福荫-lre 的胚胎在原肠胚晚期停止发育。在这项工作中，确定了突变区域两端的精确突变位点，并在突变区域的两端获得了两个长度为 1232bp 和 1845bp 的插入序列。有趣的是，在插入的 1845bp 序列中检测到一个 bmmar1 转座子。Bmmar1 具有转座元件（TEs）的 Tcl/mariner 超家族的特征，属于使用 DNA 介导的“切割和粘贴”机制进行转座的第二类 TEs。这一发现表明，福荫-lre 突变可能与 bmmar1 的“切割和粘贴”作用有关。该突变导致突变区域内 9 个基因缺失，其中红卵基因 re（BMSK0002766）不影响家蚕胚胎发育，BMSK0002765 基因在胚胎发育早期不表达。剩余 7 个基因的 RNA 干扰结果表明，信号素-1a 样基因（BMSK0002764）对福荫-lre 的胚胎致死性有重要贡献。
