Activation and Regulation Mechanisms of cGMP-dependent Protein Kinase I and II

 描述（由申请方提供）：本提案的具体目的是获得cGMP依赖性蛋白激酶I和II（PKG）cGMP结合结构域的高分辨率结构，并使用结构信息设计PKG特异性激活剂。作为cGMP的关键受体，PKG I和II介导cGMP升高药物的大多数作用，例如用于治疗许多高血压疾病的一氧化氮释放剂和用于治疗勃起功能障碍的磷酸二酯酶抑制剂。虽然PKG I和II是治疗高血压疾病如动脉和肺动脉高血压、心力衰竭、勃起功能障碍和骨质疏松症的治疗靶点，但主要由于缺乏可用的结构信息，开发特异性激活剂一直很困难。为了获得开发PKG I和II的特异性激活剂所需的结构信息，我们的小组最近确定了特异性结合cGMP并激活催化活性的人PKG I和II的调节结构域片段的晶体结构。我的长期目标是了解cGMP介导的PKG激活机制，并开发可用于治疗高血压疾病的PKG特异性激活剂。为了实现这些目标，我的计划是了解非选择性A结构域在PKG I激活中的作用，了解PKG II的环核苷酸选择性机制，筛选已知的cGMP类似物的亚型特异性结合和激活，并确定其共晶体结构，并使用所得的结构信息开发PKG I和II的亚型特异性激活剂。

 DESCRIPTION (provided by applicant): The specific aims of this proposal are to obtain high-resolution structures of the cGMP- binding domains of cGMP-dependent protein kinase I and II (PKGs) and to use the structural information to design activators specific for PKGs. As key receptors for cGMP, PKG I and II mediate most effects of cGMP-elevating drugs such as nitric oxide-releasing agents for the treatment of many hypertensive diseases and phosphodiesterase inhibitors for the treatment of erectile dysfunction. While PKG I and II are therapeutic targets fo treating hypertensive diseases such as arterial and pulmonary hypertension, heart failure, erectile dysfunction and osteoporosis, developing specific activators has been difficult mainly due to a lack of available structural information. To obtain structural information needed for developing specific activators of PKG I and II, our group recently determined crystal structures of a fragment of the regulatory domains of human PKG I and II that specifically bind cGMP and activate catalytic activity. My long-term goals are to understand the activation mechanism of PKG mediated by cGMP and to develop specific activators of PKG that can be used for treating hypertensive diseases. To achieve these goals, my plans are to understand the role of the non-selective A-domain in activation of PKG I, to understand the cyclic nucleotide selectivity mechanism of PKG II, to screen known cGMP analogs for isoform specific binding and activation, and determine their co-crystal structures and use the resulting structural information for developing isoform specific activators of PKG I and II.