Hsp90/Client Protein Interactions in the Newborn Lung

描述(申请人提供)：调节出生时肺循环适应的信号机制以及那些导致婴儿肺动脉高压(PH)发展的信号机制尚不完全清楚，是我的实验室的长期目标。Hsp90及其客户信号蛋白之间的相互作用调节正常新生儿肺循环中的血管反应，Hsp90/客户蛋白相互作用的成熟变化有助于出生后早期肺循环适应，以及慢性低氧改变Hsp90/客户蛋白相互作用扰乱新生儿肺扩张器信号通路的成熟和功能。将使用生理测量和生化技术来解决以下具体目标：(1)确定Hsp90/客户蛋白相互作用对新生仔猪肺血管功能和信号的影响；(1B)确定在正常氧饲养的健康仔猪出生2-4天和12-14天之间发生的Hsp90/客户蛋白相互作用的成熟变化；(2)确定Hsp90/客户蛋白相互作用中导致慢性(10天)低氧引起肺血管反应性和信号变化的Hsp90/客户蛋白相互作用的错乱。我们的研究集中在Hsp90与其已知的客户蛋白，内皮型一氧化氮合酶(NOS)和Akt激酶之间的相互作用，以及与胞浆前列腺素E2合成酶和血栓素合酶的新的相互作用。我们方法的核心是测量从健康仔猪和缺氧性肺高压仔猪分离的中空肺阻力动脉的血管反应。继发于慢性肺或心脏疾病的PH对目前可用的治疗方法很少有反应，而且往往是致命的。这些研究将提高对新生儿肺动脉高压对慢性低氧反应的了解，并对制定新的PH婴儿治疗策略至关重要。

DESCRIPTION (provided by applicant): The signaling mechanisms regulating pulmonary circulatory adaptation at birth and those contributing to the development of pulmonary hypertension (PH) in infants are incompletely understood and are the long-term objectives of my laboratory. This proposal addresses the hypothesis that interactions between heat shock protein 90 (Hsp90) and its client signaling proteins regulate vascular responses in the normal newborn pulmonary circulation, that maturational changes in Hsp90/client protein interactions contribute to early postnatal pulmonary circulatory adaptation, and that chronic hypoxia alters Hsp90/client protein interactions disrupting the maturation and function of dilator signaling pathways in the neonatal lung. Physiological measurements and biochemical techniques will be used to address the following specific aims: (1A) Determine the impact of Hsp90/client protein interactions on vascular function and signaling in the lungs of newborn piglets, (1B) Determine the maturational changes in Hsp90/client protein interactions that occur between day of life 2-4 and 12-14 in healthy piglets raised in normoxia and (2) Determine the derangements in Hsp90/client protein interactions that contribute to altered vascular reactivity and signaling in the lungs of piglets with PH induced by chronic (10 days) hypoxia. Our investigations focus on interactions between Hsp90 and its known client proteins, endothelial nitric oxide synthase (NOS) and Akt kinase, as well as novel interactions with cytosolic prostaglandin E2 synthase and thromboxane synthase. At the core of our methodology is measurement of vascular responses in cannulated pulmonary resistance arteries isolated from healthy piglets and piglets with hypoxia-induced PH. PH that develops secondary to chronic pulmonary or cardiac conditions is rarely responsive to currently available therapies and is frequently lethal. These studies will improve understanding of the neonatal pulmonary hypertensive response to chronic hypoxia and are critical to the formulation of novel treatment strategies for infants with PH.