Wheeler Diana E, Nijhout H F
Department of Entomology, University of Arizona, Tucson 85721, USA.
Bioessays. 2003 Oct;25(10):994-1001. doi: 10.1002/bies.10337.
The juvenile hormones of insects regulate an unusually large diversity of processes during postembryonic development and adult reproduction. It is a long-standing puzzle in insect developmental biology and physiology how one hormone can have such diverse effects. The search for molecular mechanisms of juvenile hormone action has been guided by classical models for hormone-receptor interaction. Yet, despite substantial effort, the search for a juvenile hormone receptor has been frustrating and has yielded limited results. We note here that a number of lipid-soluble signaling molecules in vertebrates, invertebrates and plants show curious similarities to the properties of juvenile hormones of insects. Until now, these signaling molecules have been thought of as uniquely evolved mechanisms that perform specialized regulatory functions in the taxon where they were discovered. We show that this array of lipid signaling molecules share interesting properties and suggest that they constitute a large set of signal control and transduction mechanisms that include, but range far beyond, the classical steroid hormone signaling mechanism. Juvenile hormone is the insect representative of this widespread and diverse system of lipid signaling molecules that regulate protein activity in a variety of ways. We propose a synthetic perspective for understanding juvenile hormone action in light of other lipid signaling systems and suggest that lipid activation of proteins has evolved to modulate existing signal activation and transduction mechanisms in animals and plants. Since small lipids can be inserted into many different pathways, lipid-activated proteins have evolved to play a great diversity of roles in physiology and development.
昆虫的保幼激素在胚胎后发育和成虫繁殖过程中调节着异常多样的生理过程。一种激素如何能产生如此多样的效应，这在昆虫发育生物学和生理学领域一直是个长期存在的谜题。对保幼激素作用分子机制的探索一直受激素 - 受体相互作用经典模型的指引。然而，尽管付出了巨大努力，寻找保幼激素受体的工作却令人沮丧，成果有限。我们在此指出，脊椎动物、无脊椎动物和植物中的许多脂溶性信号分子与昆虫保幼激素的特性有着惊人的相似之处。到目前为止，这些信号分子一直被认为是在其被发现的分类群中独特进化而来、执行特定调节功能的机制。我们发现这一系列脂类信号分子具有一些有趣的共同特性，并表明它们构成了一个庞大的信号控制和转导机制集合，其中包括但远远超出了经典的类固醇激素信号传导机制。保幼激素是这个广泛多样的脂类信号分子系统在昆虫中的代表，该系统以多种方式调节蛋白质活性。我们提出一种综合观点，从其他脂类信号系统的角度来理解保幼激素的作用，并认为蛋白质的脂类激活作用已经进化，以调节动植物中现有的信号激活和转导机制。由于小脂类分子可以插入许多不同的信号通路，脂类激活的蛋白质在生理和发育过程中发挥着多种多样的作用。
