Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
Sci Rep. 2016 Feb 1;6:20102. doi: 10.1038/srep20102.
Dusky-like (Dyl) is associated with the morphogenesis of embryonic denticle, adult sensory bristle and wing hair in Drosophila melanogaster. And whether Dyl involved in insect post-embryonic development and its signal transduction are poorly understood. Here, phylogenetic analysis revealed that dyl displayed one-to-one orthologous relationship among insects. In Tribolium castaneum, dyl is abundantly expressed at the late embryonic stage. Tissue-specific expression analysis at the late adult stage illustrated high expression of dyl in the fat body and ovary. Knockdown of dyl resulted in the defects in larval epidermal pigmentation and completely blocked the transitions from larval to pupal and pupal to adult stages of T. castaneum. We further discovered that dyl RNAi phenotypes were phenocopied by blimp-1 or shavenbaby (svb) silencing, and dyl was positively regulated by blimp-1 through svb in T. castaneum. These results suggest that Dyl functions downstream of Blimp-1 through Svb for larval epidermal pigmentation and metamorphosis. Moreover, ftz-f1 was down-regulated after RNA interference (RNAi) suppressing any of those three genes, indicating that Ftz-f1 works downstream of Dyl to mediate the effects of Blimp-1, Svb and Dyl on metamorphosis in T. castaneum. This study provides valuable insights into functions and signaling pathway of insect Dyl.
暗体 (Dyl) 与果蝇胚胎齿、成虫感觉刚毛和翅膀毛的形态发生有关。而 Dyl 是否参与昆虫胚胎后发育及其信号转导尚不清楚。在这里，系统发育分析表明 dyl 在昆虫中具有一对一的直系同源关系。在赤拟谷盗中，dyl 在胚胎晚期大量表达。在成虫晚期的组织特异性表达分析表明，dyl 在脂肪体和卵巢中高表达。dyl 的敲低导致幼虫表皮色素沉着缺陷，并完全阻止了赤拟谷盗从幼虫到蛹和蛹到成虫的转变。我们进一步发现，dyl RNAi 表型被 blimp-1 或 shavenbaby (svb) 沉默所模拟，并且 dyl 在赤拟谷盗中通过 svb 被 blimp-1 正向调控。这些结果表明 Dyl 通过 Svb 在 Blimp-1 下游调控幼虫表皮色素沉着和变态。此外，在 RNA 干扰 (RNAi) 抑制这三个基因中的任何一个后，ftz-f1 的表达下调，表明 Ftz-f1 在下游工作，以介导 Dyl、Blimp-1、Svb 和 Dyl 对赤拟谷盗变态的影响。这项研究为昆虫 Dyl 的功能和信号通路提供了有价值的见解。
