BACKGROUND & AIMS:
:G protein-coupled receptor (GPCR) genes are large gene families in every animal, sometimes making up to 1-2% of the animal's genome. Of all insect GPCRs, the neurohormone (neuropeptide, protein hormone, biogenic amine) GPCRs are especially important, because they, together with their ligands, occupy a high hierarchic position in the physiology of insects and steer crucial processes such as development, reproduction, and behavior. In this paper, we give a review of our current knowledge on Drosophila melanogaster GPCRs and use this information to annotate the neurohormone GPCR genes present in the recently sequenced genome from the honey bee Apis mellifera. We found 35 neuropeptide receptor genes in the honey bee (44 in Drosophila) and two genes, coding for leucine-rich repeats-containing protein hormone GPCRs (4 in Drosophila). In addition, the honey bee has 19 biogenic amine receptor genes (21 in Drosophila). The larger numbers of neurohormone receptors in Drosophila are probably due to gene duplications that occurred during recent evolution of the fly. Our analyses also yielded the likely ligands for 40 of the 56 honey bee neurohormone GPCRs identified in this study. In addition, we made some interesting observations on neurohormone GPCR evolution and the evolution and co-evolution of their ligands. For neuropeptide and protein hormone GPCRs, there appears to be a general co-evolution between receptors and their ligands. This is in contrast to biogenic amine GPCRs, where evolutionarily unrelated GPCRs often bind to the same biogenic amine, suggesting frequent ligand exchanges ("ligand hops") during GPCR evolution.
背景与目标:
:G蛋白偶联受体(GPCR)基因是每只动物的大基因家族,有时占动物基因组的1-2%。在所有昆虫GPCR中,神经激素(神经肽,蛋白激素,生物胺)GPCR尤其重要,因为它们与配体一起在昆虫生理学中占据较高的层次,并引导关键的过程(例如发育,繁殖和繁殖)。行为。在本文中,我们回顾了我们对果蝇GPCR的当前知识,并使用此信息来注释蜜蜂蜜蜂Apis mellifera最近测序的基因组中存在的神经激素GPCR基因。我们在蜜蜂中发现了35个神经肽受体基因(果蝇中为44个)和两个基因,编码富含亮氨酸重复序列的蛋白激素GPCR(果蝇中为4个)。此外,蜜蜂有19个生物胺受体基因(果蝇中有21个)。果蝇中大量的神经激素受体可能是由于近期果蝇进化过程中发生的基因重复。我们的分析还得出了本研究中鉴定的56种蜜蜂神经激素GPCR中40种可能的配体。此外,我们对神经激素GPCR的进化以及其配体的进化和共同进化做了一些有趣的观察。对于神经肽和蛋白激素GPCR,似乎在受体及其配体之间存在共同的共同进化。这与生物胺GPCR相反,生物胺GPCR在进化上不相关的GPCR通常与相同的生物胺结合,表明在GPCR进化过程中频繁的配体交换(“配体啤酒花”)。