A New Imaging Method for Ocular Lens Protein Modifications

描述（由申请人提供）：晶状体为蛋白质生物化学提供了一个独特的环境，需要在生物体的整个生命周期中保持透明度。细胞器丢失后，很少发生蛋白质周转，允许翻译后修饰在生物体的一生中积累。正是这些修饰与蛋白质聚集、不溶化和白内障形成有关。尽管许多修饰已被编目，但修饰蛋白在人类晶状体中的空间分布却很少被研究。正是改变的空间模式可以区分正常发育或调节改变与年龄相关和白内障特异性改变。本研究的目的是开发一种新的成像技术，用于测量透镜蛋白的高空间分辨率分布。MALDI组织成像已应用于几种组织，以绘制肿瘤特异性蛋白质，器官特异性蛋白质分布，以及感染组织与正常组织的分布。晶状体蛋白成像及其修饰的前景是揭示白内障发生的新机制。事实上，在初步研究中，两种以前未报道的修饰已经直接从晶状体组织中成像。本开发应用的第一个目的是确定成像晶状体蛋白的最佳样品制备和图像采集要求。第二个目标是将目标1中确定的条件应用于不同年龄和白内障状态的人体晶状体成像。最终，将获得新的晶状体蛋白修饰的空间分辨信息，这些信息可用于制定关于白内障形成的假设，并导致延迟安抚发作的策略。公共卫生相关性：提出了一种新的晶状体组织成像技术的发展，其中年龄和白内障特异性蛋白质修饰的空间分布将被获得。通过这项新技术获得的晶状体蛋白修饰的空间模式的知识将导致新的机制假设和白内障的潜在治疗靶点。

DESCRIPTION (provided by applicant): The ocular lens provides a unique environment for protein biochemistry necessitated by the need to maintain transparency over the lifetime of the organism. After organelle loss, little protein turnover occurs allowing post-translational modifications to accumulate over the lifetime of the organism. It is these modifications that have been linked to protein aggregation, insolubilization, and cataract-formation. Although a number of modifications have been cataloged, the spatial distribution of modified proteins in the human lens has been little-studied. It is precisely the spatial patterns of modification that can differentiate normal developmental or regulatory modifications from age-related and cataract-specific modifications. The objective of this proposal is to develop a new imaging technology for measuring lens protein distributions with high spatial resolution. MALDI tissue imaging has been applied to several tissues to map tumor-specific proteins, organ-specific protein distributions, and distributions in infected versus normal tissues. The promise of imaging lens proteins and their modifications is that new mechanisms of cataractogenesis will be revealed. Indeed, in preliminary studies, two previously unreported modifications have been imaged directly from lens tissue. The first aim of this developmental application is to determine optimum sample preparation and image acquisition requirements for imaging ocular lens proteins. The second aim is apply the conditions determined in aim 1 to image human lenses of varying age and cataract status. Ultimately, new spatially-resolved information on lens protein modification will be acquired that can be used to formulate hypotheses on cataract formation and lead to strategies to delay the onset of pacification. PUBLIC HEALTH RELEVANCE: The development of a new imaging technology is proposed for ocular lens tissue in which the spatial distributions of age- and cataract-specific protein modifications will be acquired. Knowledge of spatial patterns of lens protein modifications achieved by this new technology will lead to new mechanistic hypotheses and potential therapeutic targets for cataracts.