COMPOUNDS TARGETING THE ALPHA-2 GABA-A RECEPTOR SUBTYPE

描述（由申请人提供）：仍然需要有效而安全的治疗焦虑症和相关疾病的方法。目前的治疗方法，如苯二氮卓类药物，靶向许多γ-氨基丁酸受体（GABA-A受体）亚型是有效的，但患者遭受许多副作用。由于缺乏有效的先导物优化和药物发现所需的结构/功能信息，仅靶向抗焦虑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绘负责与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：  无义抑制方法用于将非天然氨基酸掺入（α-1）2（β-3）2（γ-2）和（α-2）2（β-3）2（γ-2）GABA-A受体亚型中的特定位置的用途。这涉及定点诱变研究，其中将非天然氨基酸掺入GABA-A受体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GABA-A受体的五种结构不同的变构调节剂对每种突变受体的活性，并开发α-2受体亚型选择性的Receptophore TM模型。II期将使用I期期间产生的信息来设计和合成α-2受体亚型选择性GABA-A受体化合物。进一步的铅优化，药理学和毒理学将为治疗焦虑症提供更安全的疗法。

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.