保幼激素在昆虫中的分子作用机理  

Molecular mechanisms of the insect juvenile hormone

作　　者：金敏娜[1] 林欣大[1] 

机构地区：[1]中国计量学院生命科学学院浙江省生物计量与检验检疫重点实验室,杭州310018

出　　处：《生态学报》2014年第6期1361-1370,共10页Acta Ecologica Sinica

基　　金：国家重点基础研究发展计划(2010CB126200)

摘　　要：随着分子生物学技术的快速发展,对生态环境中各类生物的研究,包括对生物某些特定基因结构和功能的研究等逐步拓展和加深。保幼激素(Juvenile Hormone,JH)是由咽侧体(Corpus Allatum,CA)分泌的,在昆虫发育、变态和生殖过程中起重要作用的激素。目前对JH信号传导途径的作用机理还不十分清楚。现有研究表明,Kruppel homolog-1(Kr-h1)是一种含C2H2锌指结构的转录因子,处于保幼激素信号途径下游,在保幼激素信号通路中起着重要作用。已报道的Kr-h1基因的功能主要包括:调控幼虫生长发育和变态,与蜜蜂的觅食行为密切相关,参与果蝇幼体神经细胞的形成等等。对就近十年来Kr-h1基因的特性和功能研究作一个综述以了解不同昆虫中保幼激素的分子作用机制,为开发生物农药奠定理论基础,也为维护良好的生态环境作出理论贡献。Following the rapid development of molecular biology techniques, many studies have been carried out of specific gene structures and functions, including those in ecological environments. Juvenile hormone （JH） is an important insect hormone that regulates insect larval development, reproduction, and metamorphosis, although the molecular mechanism behind this remains unclear. The transcription factor Kruppel-homolog 1（Kr-h1） acts downstream of the JH receptor and plays a key role in the JH signaling pathway. It has been identified in over 21 insect species, and sequence analysis has shown it to contain 2-8 C2H2-type zinc-finger motifs, which are highly conserved among Kr-h1 proteins. We previously found that zinc-fingers Zn2-Zn7 are more conserved than others in all insect species we compared. Interestingly, we found that the jewel wasp Nasonia vitripennis only contains two zinc-fingers, Zn4 and Zn7, while the body louse Pediculus humanus corporis contains all zinc-fingers except Zn7. As N. vitripennis and P. humanus were the only two parasitoids among the 21 insect species examined, it is possible that zinc fingers might be lost during evolution. Studies in Drosophila melanogester, Bombyx mori, Tribolium castaneum, and Frankliniella occidentalis revealed that Kr-h1 is required for embryonic development and metamorphosis, and that its down-regulation results in development of the precocious phenotype. Knockdown of Kr-h1 by RNAi in the brown planthopper Nilaparvata lugens showed that this gene is required for normal wing and external genitalia development. Kr-h1 is also involved in neuron development, the regulation of photoreceptor maturation, larval growth, insect development and metamorphosis, and the formation of Drosophila melanogaster neurons. In addition, it controls the foraging behavior of honey bees through affecting the expression of the cGMP-mediated activation of protein kinase G. The expression of Kr-h1 is induced by JH and its mimics. The Bombyx mori juvenile hormone response element （bmJHRE

关 键 词：生态环境 保幼激素 信号通路 Kruppel homolog-1 锌指结构 

分 类 号：Q966[生物学—昆虫学]