Integrin Regulation of Stretch-Activated Myometrial Signaling During Pregnancy an

个人描述(申请人提供)：我在伊利诺伊大学生殖生物学培训项目下获得博士学位。在这个项目中，学生和教职员工之间有相当大的互动和讨论，研究重点广泛。RBTP教师鼓励学生充分质疑，形成他们自己的假设，设计他们自己的实验，并写出他们自己的建议。我的课程主要集中在生殖生理学，但也包括生物化学和细胞生物学、发育生物学、遗传学、微生物学和研究伦理学。在攻读博士学位之前，我有幸在三个备受赞誉的实验室工作，研究重点从分子生物学到群体遗传学，再到病理学。2003年，我接受了基础电生理学方面的短期博士后培训。2004年至2009年间，为了抚养两个孩子，我暂时停止了研究。在这段时间里，我不断了解最新的科学文献，并在业余时间参与研究α7整合素在胎盘发育和胚胎血管形成中的作用。我非常怀念研究，我非常有动力回来。我最近开始与伊恩·巴克斯顿博士合作。巴克斯顿博士是一位非常成功的科学家，在怀孕期间子宫功能的研究方面有着长期的记录。巴克斯顿博士罕见地将医学知识、对细节的关注和远见结合在一起。我们的讨论激发了这个提案中提出的想法，我想不出一个更好的导师来指导这个项目。内华达大学医学院的教职员工因其在平滑肌生理学方面的专业知识而广为人知。他们在平滑肌生理学方面的知识对我在分子和细胞生物学以及生殖生理学方面的背景是完美的补充。在这个奖项的指导阶段，我将学习肌肉力学和电生理学方面的新实验技能，这些技能将为解决早产的巨大问题提供令人兴奋的结果。因此，内华达大学是一个理想的机构，在那里我可以实现我的职业目标，成为一名独立的研究员。我在生殖生理学方面的全面培训，再加上分子生物学、细胞生物化学和最近的平滑肌肉力学方面的广泛培训，使我为研究人类早产和产后分娩中整合素作用这一令人兴奋和高度相关的话题做好了独特的准备。从长远来看，我希望获得一份教职，并指导基础研究，这将有助于更好地理解早产以及如何预防早产。这一奖项将使我从博士后职位晋升为教职员工。我希望在分子水平上对引产的调节有进一步的了解。在医学院这里的药理学系有一个预约，这将是我找到阻止早产的药物的理想地点。在怀孕期间，分娩的开始依赖于子宫肌层从静止状态到收缩状态的激活。子宫收缩的启动需要内分泌和牵张诱导的信号通路的激活。拉伸诱导途径背后的分子机制才刚刚开始阐明，然而最近的数据表明，在足月人的子宫肌层组织中，粘着斑激酶(FAK)被激活，这是整合素参与的一个强烈指标(Li等，2009)。FAK-ERK通路的激活强烈表明整合素受体的参与是肌层收缩所必需的。由于整合素已被证明在平滑肌收缩中起关键作用，我推测至少有一种整合素异源二聚体对肌层收缩是必不可少的。我将确定在足月妊娠的人子宫肌层中存在和/或上调哪些整合素亚单位，并确定单个整合素亚单位是否调节人类子宫组织拉伸诱导的收缩。我将创建一个可诱导的小鼠模型，在该模型中，整合素21的产生可以在怀孕期间阻止子宫肌层的产生。我将使用这些小鼠来确定21整合素的缺失是否会降低子宫肌层对体外拉伸的收缩能力，改变下游信号通路，或者导致产后分娩。我还将测试子宫中整合素-ERK激活增强会导致早产的假设。我将比较早产和早产人子宫和足月子宫组织切片中相关整合素的表达，并确定FAK-ERK下游激活在早产和晚产人子宫肌层中是否发生变化。明确整合素介导的信号通路，调节拉伸诱导的子宫肌层激活，将对治疗早产和足月后分娩具有重要意义。

DESCRIPTION (provided by applicant): I received my PhD from the University of Illinois under the Reproductive Biology Training Program. In this program there is considerable interaction and discussion among the students and faculty with a wide range of research focuses. The RBTP faculty encourages students to be very questioning, form their own hypotheses, design their own experiments, and write their own proposals. My coursework was concentrated on reproductive physiology but also included biochemistry and cell biology, developmental biology, genetics, microbiology, and research ethics. Prior to my PhD I was fortunate to work in three highly regarded laboratories with research focuses ranging from molecular biology to population genetics to Pathology. In 2003 I received brief postdoctoral training in basic electrophysiology. I took a break from research between 2004 and 2009 to raise two children. During this time I kept current with the scientific literature and contributed to work investigating the role of the alpha 7 integrin in placental development and embryonic vascularization in my spare time. I have missed research very much and am highly motivated to return. I have recently begun working with Dr. Iain Buxton. Dr. Buxton is a highly successful scientist with a long track record of research in uterine function during pregnancy. Dr. Buxton possesses a rare combination of medical knowledge, attention to detail, and vision. Our discussions stimulated the ideas presented in this proposal and I cannot think of a better mentor for this project. The faculty here at the University of Nevada School of Medicine is widely recognized for their expertise in smooth muscle physiology. Their knowledge of smooth muscle physiology is the perfect complement for my background in molecular and cellular biology and the physiology of reproduction. During the mentored phase of this award I will learn new experimental skills in muscle mechanics and electrophysiology that will provide exciting results for the huge problem of preterm labor. Therefore, the University of Nevada is an ideal institution in which to further my career goals to become an independent researcher. My comprehensive training in Reproductive Physiology combined with extensive training in molecular biology, cellular biochemistry, and more recently smooth muscle mechanics have uniquely prepared me to investigate the exciting and highly relevant topic of integrin action during human preterm and post-term labor. In the longer term I would like to obtain a faculty appointment and to direct basic research that will lead to a better understanding of preterm labor and how to prevent it. This award would allow me to move from a postdoctoral position to a faculty appointment. I hope to gain further insights into the regulation of labor induction at the molecular level. An appointment in the Pharmacology Department here at the medical school would ideally situate me to identify pharmacological agents to halt preterm labor. During pregnancy the onset of labor is dependent on activation of the uterine myometrium from the quiescent to the contractile state. The initiation of uterine contractions requires the activation of both endocrine and stretch-induced signaling pathways. The molecular mechanisms underlying the stretch-induced pathway are just beginning to be elucidated, however recent data have shown that Focal Adhesion Kinase (FAK) is activated in term human myometrial tissue, a strong indicator of integrin engagement (Li et al., 2009). Activation of the FAK-ERK pathway strongly suggests integrin receptor engagement is required for myometrial contraction. Because integrins have been shown to play pivotal roles in smooth muscle contractility, I hypothesize at least one integrin heterodimer will be essential to myometrial contractility. I will determine which integrin subunits are present and/or upregulated in term pregnant human myometrium and determine if individual integrin subunits regulate stretch-induced contraction in human uterine tissue. I will create an inducible mouse model in which integrin 21 production can be blocked in the uterine myometrium during pregnancy. I will use these mice to determine if loss of 21 integrin decreases myometrial contractility in response to stretch in vitro, alters downstream signaling pathways, or results in post-term labor. I will also test the hypothesis that enhanced integrin-ERK activation in the uterus contributes to preterm labor. I will compare the expression of relevant integrins in tissue sections from pre-term and post-term human uterus compared to term uterus and determine if downstream FAK-ERK activation is altered in pre-term and post-term human myometrium. Defining the integrin- mediated signaling pathways that regulate stretch induced activation of the uterine myometrium will have important implications for treating preterm and post term labor.