Regulation of guanylyl cyclase

描述(申请人提供)：可溶性鸟苷酸环化酶(SGC)是非环GMP(CGMP)信号级联中的关键酶之一，参与平滑肌松弛、抑制血小板聚集和神经传递。SGC是目前用于治疗心血管疾病的各种药理化合物的靶标。然而，调控sGC活性或表达的机制却知之甚少。要有效地操纵sGC依赖的cGMP合成用于治疗目的，需要了解参与sGC水平和活性调节的途径。本研究的目的是确定异位效应器激活酶的分子机制，包括开发sGC的NO非独立调控方法，研究sGC表达的调控机制，以及分析sGC活性和表达的短期和长期调节对细胞生理的影响。为了实现这一目标，一个结构性激活的sGC突变体将在一个细胞模型中表达，提供高水平的cGMP，而参与sGC功能异源二聚体形成的结构域的表达将导致酶水平降低和cGMP的NO依赖合成减少。将鉴定和鉴定sGC基因的启动子片段以及sGC的转录后调控机制将建立人类细胞培养模型，并将确定sGC的短期和长期调控对细胞生理的影响。了解sGC的调控机制将有助于我们理解sGC/cGMP系统在多种生物学过程中的作用。

DESCRIPTION (provided by applicant): Soluble guanylyl cyclase (sGC) is one of the crucial enzymes in the NO-cyclic GMP (cGMP) signaling cascade involved in smooth muscle relaxation, inhibition of platelet aggregation, and neurotransmission. sGC is the target of various pharmacological compounds currently used for treatment of cardiovascular disorders. However, the mechanisms governing stimulation of activity or expression of sGC are poorly understood. Effective manipulation of sGC-dependent synthesis of cGMP for therapeutic purposes requires understanding of the pathways involved in regulation of sGC levels and activity. The goal of this proposal is to determine the molecular mechanism of enzyme activation by alisoteric effectors including development of approaches for NO-independent regulation of sGC, investigation of the mechanisms regulating sGC expression, and analysis of the effects of short-term and long-term modulation of sGC activity and expression on cell physiology. To achieve this goal, a constitutively activated sGC mutant will be expressed in a cell model providing for elevated levels of cGMP, whereas expression of domains involved in formation of functional heterodimers of sGC will result in decreased enzyme levels and lowered NO-dependent synthesis of cGMP. The promoter fragments of sGC genes will be identified and characterized as well as the mechanisms of post-transcriptional regulation of sGC Human cell culture models will be developed and the effects of short-term and long-term sGC regulation on cell physiology will be determined. The knowledge of the mechanism of sGC regulation will advance our understanding of the role of sGC/cGMP system in various biological processes.