CYP18A1 regulates tissue-specific steroid hormone inactivation in Bombyx mori.
CYP18A1 regulates tissue-specific steroid hormone inactivation in Bombyx mori.
复制标题
CYP18A1 调节家蚕组织特异性类固醇激素失活。
DOI：
10.1016/j.ibmb.2014.08.007
复制
发表时间：
2014-11
影响因子：
3.8
通讯作者：
Tan A
中科院分区：
文献类型：
--
作者：
Li Z;Ge X;Ling L;Zeng B;Xu J;Aslam AF;You L;Palli SR;Huang Y;Tan A
昆虫的发育和变态受保幼激素和蜕皮激素两种主要激素的调节。尽管20-羟基蜕皮激素（20-hydroxyecdysone，20 E）是昆虫发育转变的关键调节因子，但其代谢途径，尤其是失活途径至今尚未完全阐明。细胞色素P450酶CYP 18 A1通过26-羟基化作用在昆虫类固醇激素失活中起关键作用。在这里，我们确定了两个CYP 18（BmCYP 18 A1和BmCYP 18 B1）直系同源的鳞翅目模式昆虫，家蚕。有趣的是，BmCYP 18 A1基因主要在中间丝腺（MSG）中表达，而BmCYP 18 B1在B中普遍表达。森。BmCYP 18 A1在体外可被20 E诱导，提示其在20 E代谢中的作用。使用二元Gal 4/UAS转基因系统，我们异位过表达BmCYP 18 A1在MSG特异性的方式与Sericin 1-Gal 4（Ser-Gal 4）驱动程序或在普遍存在的方式与肌动蛋白3-Gal 4（A3-Gal 4）驱动程序。BmCYP 18 A1在MSG或所有组织中的异位过表达导致转基因动物在末龄幼虫阶段的发育停滞。表达BmCYP 18 A1的转基因动物中的20 E滴度低于对照动物中的水平。尽管BmCYP 18 A1的MSG特异性表达的生物学意义尚不清楚，但我们的结果提供了第一个证据，即在大多数节肢动物中保守的BmCYP 18 A1参与了B中的组织特异性类固醇激素失活。森。
Insect development and metamorphosis are regulated by two major hormones, juvenile hormone and ecdysteroids. Despite being the key regulator of insect developmental transitions, the metabolic pathway of the primary steroid hormone, 20-hydroxyecdysone (20E), especially its inactivation pathway, is still not completely elucidated. A cytochrome P450 enzyme, CYP18A1, has been shown to play key roles in insect steroid hormone inactivation through 26-hydroxylation. Here, we identified two CYP18 (BmCYP18A1 and BmCYP18B1) orthologs in the lepidopteran model insect, Bombyx mori. Interestingly, BmCYP18A1 gene is predominantly expressed in the middle silk gland (MSG) while BmCYP18B1 expresses ubiquitously in B. mori. BmCYP18A1 is induced by 20E in vitro, suggesting its role in 20E metabolism. Using the binary Gal4/UAS transgenic system, we ectopically overexpressed BmCYP18A1 in a MSG-specific manner with a Sericin1-Gal4 (Ser-Gal4) driver or in a ubiquitous manner with an Actin3-Gal4 (A3-Gal4) driver. Ectopic overexpression of BmCYP18A1 in MSG or in all tissues resulted in developmental arrestment of transgenic animals during the final instar larval stage. The 20E titers in the transgenic animals expressing BmCYP18A1 were lower compared to the levels in the control animals. Although the biological significance of MSG-specific expression of BmCYP18A1 is unclear, our results provide the first evidence that BmCYP18A1, which is conserved in most arthropods, is involved in a tissue-specific steroid hormone inactivation in B. mori.