COMPOUNDS TARGETING THE ALPHA-2 GABA-A RECEPTOR SUBTYPE

描述（由申请人提供）：持续需要有效且安全的治疗焦虑和相关障碍的方法。目前的治疗方法，如针对许多γ -氨基丁酸受体（GABA-A受体）亚型的苯二氮卓类药物是有效的，但患者会受到许多副作用的影响。由于缺乏有效的先导优化和药物发现所需的结构/功能信息，仅针对抗焦虑α -2 GABA-A受体亚型的化合物的鉴定受到阻碍。该项目的第一阶段将使用非天然氨基酸的定点诱变来描述与α -2 GABA-A受体亚型结合的结构-功能关系。第一阶段的目标是：利用无义抑制方法将非天然氨基酸整合到（α -1）2(β -3)2（γ -2）和（α -2）2(β -3)2(γ -2) GABA-A受体亚型的特定位置。这包括位点定向诱变研究，其中非天然氨基酸将被掺入GABA-A受体的α和γ亚基的特定位置。突变蛋白的验证将使用电生理记录技术。评估天然配体GABA和五种结构多样的GABA- a受体变构调节剂对每种突变受体的活性，并建立α -2受体亚型选择性的受体载体TM模型。II期将利用I期产生的信息设计合成α -2受体亚型选择性GABA-A受体化合物。进一步的先导优化、药理学和毒理学将为焦虑症的治疗提供更安全的治疗方法。

DESCRIPTION (provided by applicant): There continues to be a need for effective yet safe treatments for anxiety and related disorders. Current treatments such as the benzodiazepines which target many of the gamma-aminobutyric acid receptor (GABA-A receptor) subtypes are effective, but patients suffer from a number of side-effects. The identification of compounds targeting only the anxiolytic alpha-2 GABA-A receptor subtype has been hampered by a lack of structure/function information needed for effective lead optimization and drug discovery. Phase I of this project will use site-directed mutagenesis of unnatural amino acids to delineate the structure-functions relationships responsible for binding to the alpha-2 GABA-A receptor subtype. The phase I goals are:  The use of the nonsense suppression method for incorporating unnatural amino acids into specific positions in the (alpha-1)2(beta-3)2(gamma-2) and (alpha-2)2(beta-3)2(gamma-2) GABA-A receptor subtypes. This involves site-directed mutagenesis studies in which unnatural amino acids will be incorporated at specific positions on the alpha and gamma subunits of GABA-A receptor. Validation of the mutated proteins will be using electrophysiological recording techniques.  Assess the activity of the natural ligand GABA and five structurally diverse allosteric modulators of GABA-A receptor against each of the mutated receptors and develop a Receptophore TM model of alpha-2 receptor subtype selectivity. Phase II will use the information generated during Phase I to design and synthesize alpha-2 receptor subtype selective GABA-A receptor compounds. Further lead optimization, pharmacology and toxicology will provide safer therapies for the treatment of anxiety disorders.