BIOPHYSICAL CHANGES IN CELL MEMBRANES DURING APOPTOSIS AND CELLULAR TRAUMA

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 分泌型磷脂酶A2（sPLA 2）与脂质双层结合并催化磷脂的水解。 正常情况下，细胞会抵抗这种酶的作用，但在凋亡或创伤期间，它们变得敏感。 我们研究小组的重点是了解当真核细胞受到细胞内钙离子升高的创伤或通过各种手段诱导凋亡时，真核细胞膜会发生什么物理变化。 目的是了解膜结构和细胞死亡之间的关系，以及膜结构和磷脂酶A2的作用之间的关系。 用双光子显微镜研究膜探针如laurdan和patman的荧光，以区分发生在质膜上的变化和那些属于内膜的变化。 此外，这些技术使我们能够确定膜特性的横向空间分布及其与细胞凋亡和酶活性的关系。 在过去，这项工作一直局限于静态测量。 计划开始使用FCS来评估细胞凋亡和创伤过程中膜特性动力学的潜在变化。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Secretory phospholipase A2 (sPLA2) binds to lipid bilayers and catalyzes hydrolysis of phospholipids. Normally, cells resist the enzyme's action, but they become susceptible during apoptosis or trauma. The focus of our research group is to understand what physical changes occur in the membranes of eukaryotic cells when they are traumatized by elevated intracellular calcium or induced into apoptosis by various means. The purpose is to understand the relationship between membrane structure and cell death and between membrane structure and the action of phospholipase A2. The fluorescence of membrane probes such as laurdan and patman are studied by two-photon microscopy to separate changes occuring at the plasma membrane from those that pertain to internal membranes. Moreover, these techniques allow us to identify the lateral spatial distribution of membrane properties and their relationship to apoptosis and enzyme activity. In the past, the work has been confined to static measurements. Plans are in place to begin using FCS to assess potential changes in the dynamics of membrane properties during apoptosis and trauma.