Cloning and characterization of Methoprene-tolerant (Met) and Kruppel homolog 1 (Kr-h1) genes in the wheat blossom midge, Sitodiplosis mosellana
Cloning and characterization of Methoprene-tolerant (Met) and Kruppel homolog 1 (Kr-h1) genes in the wheat blossom midge, Sitodiplosis mosellana
复制标题
DOI：
10.1111/1744-7917.12638
复制
发表时间：
2020-04-01
期刊：
影响因子：
4
通讯作者：
Zhu-Salzman, Keyan
中科院分区：
文献类型：
--
作者：
Cheng, Wei-Ning;Li, Xue-Jiao;Zhu-Salzman, Keyan
保幼激素（JH）是一种生长调节剂，能抑制蜕皮激素诱导的昆虫变态，控制昆虫的发育和滞育。甲氧普仑耐受蛋白（Methoprene-tolerant，Met）和Kruppel同源蛋白1（Kr-h1）是参与JH作用的两种蛋白。为了深入了解Met和Kr-h1基因在麦红吸浆虫发育中的作用，我们从麦红吸浆虫中克隆了Met和Kr-h1基因的全长互补DNA。SmMet编码一个推定的蛋白质，其中包含三个典型的bHLH-PAS家族的结构域和八个保守的氨基酸残基JH结合的重要。SmKr-h1编码的蛋白质与其他物种中的对应物具有高度的序列同源性，并包含所有8个高度保守的DNA结合锌指基序。SmMet和SmKr-h1的表达模式受到发育调控，JH III也有反应。它们的mRNA丰度随着幼虫进入3龄早期、滞育前和维持阶段而增加，并在滞育后的静止期达到峰值，这种模式与该物种的JH滴度相关。与SmMet表达减少不同，SmKr-h1 mRNA在滞育后发育中后期表达增加。局部应用JH III滞育幼虫也诱导这两个基因的剂量依赖性的方式。SmMet和SmKr-h1的表达在蛹前期明显下降，雌成虫的表达量显著高于雄成虫。这些结果表明，JH响应SmMet和SmKr-h1可能在滞育诱导和维持以及滞育后的静止和成虫繁殖中起关键作用，而从幼虫到蛹的变态可能与它们的表达减少有关。
Juvenile hormone (JH), a growth regulator, inhibits ecdysteroid-induced metamorphosis and controls insect development and diapause. Methoprene-tolerant (Met) and Kruppel homolog 1 (Kr-h1) are two proteins involved in JH action. To gain some insight into their function in development of Sitodiplosis mosellana, an insect pest undergoing obligatory larval diapause at the mature 3rd instar stage, we cloned full-length complementary DNAs of Met and Kr-h1 from this species. SmMet encoded a putative protein, which contained three domains typical of the bHLH-PAS family and eight conserved amino acid residues important for JH binding. SmKr-h1 encoded a protein showing high sequence homology to its counterparts in other species, and contained all eight highly conserved Zn-finger motifs for DNA-binding. Expression patterns of SmMet and SmKr-h1 were developmentally regulated and JH III responsive as well. Their mRNA abundance increased as larvae entered early 3rd instar, pre-diapause and maintenance stages, and peaked during post-diapause quiescence, a pattern correlated with JH titers in this species. Different from reduced expression of SmMet, SmKr-h1 mRNA increased at mid-to-late period of post-diapause development. Topical application of JH III on diapausing larvae also induced the two genes in a dose-dependent manner. Expression of SmMet and SmKr-h1 clearly declined in the pre-pupal phase, and was significantly higher in female adults than male adults. These results suggest that JH-responsive SmMet and SmKr-h1 might play key roles in diapause induction and maintenance as well as in post-diapause quiescence and adult reproduction, whereas metamorphosis from larvae to pupae might be correlated with their reduced expression.