G protein-gated K+ channels and inhibitory signaling

描述(由申请人提供)：神经元G蛋白门控内向整流钾(GIRK)通道介导许多神经递质和相关药物滥用的突触后抑制效应。我研究的长期目标是了解GIRK通道如何影响与特定神经递质信号通路相关的行为。为了实现这一目标，我们需要了解天然GIRK通道多样性的功能含义，我们需要开发出以分子精度干扰GIRK通道的方法。因此，这项建议的目标是确定亚基组成如何影响GIRK通道和相关信号分子之间的相互作用。我们的工作假设是，亚基组成决定了GIRK通道和神经元蛋白之间的相互作用，从而促进了与适当的G蛋白偶联受体的偶联。这一工作假说将通过细胞生物学、生化、电生理学和行为学实验来验证，这些实验检验了GIRK通道和GABAB受体之间的强大耦合。我们将利用一组强大的小鼠基因敲除系和定制的抗体来确定促进GIRK2通道和GABAB受体之间强大功能相互作用的结构元件(AIM#1)，确定GIRK通道亚单位组成如何影响与内源性神经元蛋白的相互作用(AIM#2)，并研究亚基组成如何影响GIRK通道对GABAB受体激活的行为效应的贡献(AIM#3)。在解决标准重组方法难以解决的GIRK通道和G蛋白信号的相关问题的同时，拟议的研究还将为涉及GABAB受体和/或GIRK通道的信号选择性扰动提供新的干预点。在GABAB依赖信号的背景下，这种进展可能转化为治疗癫痫、疼痛和成瘾的新疗法。与公共卫生的相关性。所有用于治疗人类疾病或痛苦的药物都会产生有益和不利的影响。本申请提出的工作的前提是，如果我们更好地了解药物给药的复杂生理和行为反应背后的分子机制，就可以强调许多药物的有益作用，或抑制其负面影响。

DESCRIPTION (provided by applicant): Neuronal G protein-gated inwardly rectifying K+ (GIRK) channels mediate the postsynaptic inhibitory effect of many neurotransmitters and related drugs of abuse. The long-term goal of my research is to understand how GIRK channels shape behaviors associated with specific neurotransmitter signaling pathways. To accomplish this objective, we need to understand the functional implications of native GIRK channel diversity, and we need to develop the means to perturb GIRK channels with molecular precision. Accordingly, the goal of this proposal is to determine how subunit composition influences interactions between GIRK channels and related signaling molecules. Our working hypothesis is that subunit composition dictates interactions between GIRK channels and neuronal proteins that facilitate coupling with appropriate G protein-coupled receptors. The working hypothesis will be tested with cell biological, biochemical, electrophysiological, and behavioral experiments that examine the robust coupling between GIRK channels and the GABAB receptor. We will exploit the existence of a powerful set of mouse knockout lines and custom-derived antibodies to identify structural elements promoting robust functional interactions between GIRK2-containing channels and GABAB receptors (AIM #1), to determine how GIRK channel subunit composition influences interactions with endogenous neuronal proteins (AIM #2), and to examine how subunit composition influences the contribution of GIRK channels to the behavioral effects of GABAB receptor activation (AIM #3). While addressing issues related to GIRK channels and G protein signaling that have been refractory to standard recombinant approaches, the proposed research will also suggest novel points of intervention for the selective perturbation of signaling involving GABAB receptors and/or GIRK channels. In the context of GABAB-dependent signaling, such progress could translate into novel therapies for the treatment of epilepsy, pain, and addiction. Relevance to public health. All drugs used to treat human disease or distress produce both beneficial and untoward effects. The premise of the work presented in this application is that the beneficial effects of many drugs could be emphasized, or the negative effects suppressed, if we understood better the molecular mechanisms underlying the complex physiological and behavioral responses to drug administration.