Evans Peter D, Maqueira Braudel
The Inositide Laboratory, The Babraham Institute, Cambridge, CB2 4AT, UK.
Invert Neurosci. 2005 Nov;5(3-4):111-8. doi: 10.1007/s10158-005-0001-z. Epub 2005 Oct 24.
Insect octopamine receptors are G-protein coupled receptors. They can be coupled to second messenger pathways to mediate either increases or decreases in intracellular cyclic AMP levels or the generation of intracellular calcium signals. Insect octopamine receptors were originally classified on the basis of second messenger changes induced in a variety of intact tissue preparations. Such a classification system is problematic if more than one receptor subtype is present in the same tissue preparation. Recent progress on the cloning and characterization in heterologous cell systems of octopamine receptors from Drosophila and other insects is reviewed. A new classification system for insect octopamine receptors into "alpha-adrenergic-like octopamine receptors (OctalphaRs)", "beta-adrenergic-like octopamine receptors (OctbetaRs)" and "octopamine/tyramine (or tyraminergic) receptors" is proposed based on their similarities in structure and in signalling properties with vertebrate adrenergic receptors. In future studies on the molecular basis of octopamine signalling in individual tissues it will be essential to identify the relative expression levels of the different classes of octopamine receptor present. In addition, it will be essential to identify if co-expression of such receptors in the same cells results in the formation of oligomeric receptors with specific emergent pharmacological and signalling properties.
昆虫章鱼胺受体是G蛋白偶联受体。它们可与第二信使途径偶联，以介导细胞内环状AMP水平的升高或降低，或细胞内钙信号的产生。昆虫章鱼胺受体最初是根据在各种完整组织制剂中诱导的第二信使变化进行分类的。如果同一组织制剂中存在不止一种受体亚型，这样的分类系统就会出现问题。本文综述了果蝇和其他昆虫章鱼胺受体在异源细胞系统中的克隆和表征方面的最新进展。基于昆虫章鱼胺受体与脊椎动物肾上腺素能受体在结构和信号特性上的相似性，提出了一种新的分类系统，将昆虫章鱼胺受体分为“α-肾上腺素能样章鱼胺受体（OctalphaRs）”、“β-肾上腺素能样章鱼胺受体（OctbetaRs）”和“章鱼胺/酪胺（或酪胺能）受体”。在未来关于单个组织中章鱼胺信号传导分子基础的研究中，确定不同类章鱼胺受体的相对表达水平至关重要。此外，确定这些受体在同一细胞中的共表达是否会导致具有特定新出现的药理学和信号特性的寡聚体受体的形成也至关重要。
