DYNAMIC STRUCTURE OF L-O AND L-D PHASES IN SPM-DOPC-CHOLESTEROL BY ESR

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 为了将SPM/DOPC/胆固醇模型脂质体系的应用扩展到真实的质膜，用ESR波谱对相界面上的LO和LD相进行了动态表征，以与真实的质膜进行比较。通过用动力学模型对ESR谱进行拟合，可以得到有序参数和动力学参数，如旋转扩散系数，这些参数可以用来表征脂相。如果模型膜相的参数表现出与真实质膜中相同自旋探针参数相似的特征，那么我们可以肯定地说模型膜与真实膜相似。可以使用许多不同的膜自旋探针来增加表征的特异性以及增加对相态的理解。这一特征与LO-LD相共存区域的“全局”连接线构型相结合，将为脂筏提供更详细的模型。

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. To expand the application of the SPM/DOPC/cholesterol model lipid system to real plasma membranes, the dynamic characterization of the Lo and Ld phases on the phase boundary by ESR spectra has been undertaken for comparison to real plasma membranes. The order parameter and dynamic parameters, such as rotational diffusion coefficients, can be obtained from fitting an ESR spectrum with a dynamic model, and these parameters can be used to characterize a lipid phase. If parameter from a model membrane phase exhibits similar characteristics to those parameters obtained from the same spin-probe in real plasma membranes, then we can say with confidence that the model membrane is similar to the real membrane. Many different membrane spin-probes can be employed to increase the specificity of the characterization as well as increasing the understanding of the phase state. This characterization combined with the "global" tie-line configuration for the Lo+Ld phase coexistence region will allow a more detailed model for lipid rafts.