Role of C/EBPbeta in mechanical regulation of MSC potential

该候选人是一名临床内分泌学家，致力于基础科学研究，在Janet Rubin博士的指导下工作了2.5年，最初是T32研究员，目前是由UNC著名的BIRCWH奖资助的初级教师。在Rubin博士的实验室，Styner博士在间充质干细胞（MSC）分化调控机制研究方面获得了大量专业知识。Rubin实验室先前的工作表明，MSC脂肪形成的机械抑制涉及PPARgamma表达的降低；候选人自己的工作提出了C/EBBeta（一种在脂肪形成早期表达的转录因子）可能通过调节PPARgamma参与机械抑制脂肪形成的假设。这一假设将在SA1中得到验证，在SA1中，C/EBBeta在MSC分化中的作用将通过底物拉伸在体外传递机械输入和在小鼠体内使用轮式跑步运动来分析。C/EBBeta)和潜在的调节因子将在机械/运动输入过程中使用分子技术进行改变。在SA2中，候选人提出机械运动诱导的C/EBBeta下调将保护MSC内质网（ER）应激。初步数据显示，机械应变作用下的间充质干细胞能够抵抗内质网应激的促凋亡作用，阻止脂肪形成，保持间充质干细胞潜能。实验将研究C/EBBeta)在体外和体内内质网应激中的作用，以及运动通过限制C/EBBeta)的表达来保护内质网应激的能力。运动通过C/EBBeta调节脂肪生成和内质网应激的作用将代表运动有益作用的新机制。候选人的短期职业目标包括：1)提高分子生物学的技术技能，获得显微镜和动物研究的新技能，包括体内运动模型的使用；2)提高策略和数据分析技能，以及管理实验室的技能；3)扩展她在内质网应激领域的知识；4)发展她的写作和资助技能。候选人的长期职业目标是成为一名独立的研究者，在运动对脂肪和骨骼生物学的影响方面具有专业知识，重点是了解运动影响的基本机制（MSC分化和内质网应激）。候选人的主要导师珍妮特·鲁宾博士是一位内科科学家，在培训年轻研究人员方面有着良好的记录，在骨骼生物学机械效应领域享有国际声誉。共同导师卡姆·帕特森博士在培训调查员方面有着出色的记录，他将为斯泰纳博士提供急诊室压力领域的专业知识。研究环境将提供一个富有成效的，支持性的和学院的背景，以追求拟议的研究和发展一个独立的职业生涯，候选人打算把运动对细胞的影响的知识，以治疗慢性疾病，如骨质疏松症，虚弱和肥胖。

The candidate is a clinical endocrinologist dedicated to basic science research working under the mentorship of Dr. Janet Rubin for the past 2.5 years, initially as a T32 fellow and currently as junior faculty funded by UNC's prestigious BIRCWH award. In Dr. Rubin's laboratory, Dr. Styner acquired substantial expertise in the study of mechanisms by which mesenchymal stem cell (MSC) differentiation is regulated. Prior work in the Rubin lab revealed that mechanical repression of MSC adipogenesis involves decreased expression of PPARgamma; the candidate's own work led to the hypothesis that C/EBBeta), a transcription factor expressed early in adipogenesis, might be critically involved in mechanical repression of adipogenesis through regulation of PPARgamma. This hypothesis will be tested in SA1, where C/EBBeta's role in MSC differentiation will be analyzed using substrate stretch to deliver mechanical input in vitro and using wheel based running exercise in mice in vivo. C/EBBeta) and potential regulators will be varied using molecular techniques during the mechanical/exercise input. In SA2 the candidate proposes that mechanical-exercise induced down regulation of C/EBBeta) will protect against MSC endoplasmic reticulum (ER) stress. Preliminary data show that MSCs subject to mechanical strain are resistant to the pro-apoptotic effects of ER stress, preventing adipogenesis and preserving MSC potential. Experiments will characterize C/EBBeta)'s role in ER stress in vitro and in vivo and the ability exercise to protect through limiting C/EBBeta) expression. An effect of exercise to regulate both adipogenesis and ER stress via C/EBBeta) would represent novel mechanisms for salutary effects of exercise. The candidate's short-term career goals include 1) building on her technical skills in molecular biology and acquiring new skills in microscopy and the conduct of animal research including the use of in-vivo exercise models, 2) increasing her strategy and data analysis skills, as well as skills in running a laboratory 3) expanding her knowledge in the field of ER stress and 4) developing her skills in writing and grantsmanship. The candidate's long-term-career goal is to become an independent investigator with expertise in the effects of exercise on fat and skeletal biology with an emphasis on understanding basic mechanisms affected by exercise (MSC differentiation and ER stress). The candidate's primary mentor, Dr. Janet Rubin, is a physician scientist with a record of training young investigators and with an international reputation in the field of mechanical effects in skeletal biology. The co-mentor, Dr. Cam Patterson, has an excellent record of training investigators and will provide Dr. Styner with content area expertise in the field of ER stress. The research environment will provide a productive, supportive and collegial background to pursue the proposed research and to develop an independent career where the candidate intends to bring knowledge of exercise effects on cells to the treatment of chronic diseases such as osteoporosis, frailty and obesity.