A Unified Reporter Gene for Multi-Modality Imaging

描述(由申请人提供)： 了解基因功能是一项基本但仍然具有挑战性的任务。它通常涉及用报告基因分析实时监测活细胞和组织中的基因转录和调控。一种可以在活细胞和动物中工作的报告基因将非常有价值，但目前还无法获得。本研究的总体目标是开发一个整合的报告基因系统，该系统既适用于单个活细胞的基因表达成像，也适用于包括人类在内的整个活动物的基因表达成像。 氨苄西林耐药基因(编码细菌酶，β-内酰胺酶)是光学测量单个活的哺乳动物组织培养细胞中基因表达的杰出报告。要将这种报告基因推广到整个活着的动物，将需要开发新的底物。我们将设计和合成新的底物，用于用正电子发射断层扫描(PET)对整个活着的小鼠的转基因表达进行成像。这些新的探针将在移植了肿瘤的活体小鼠身上得到验证。将评估它们的灵敏度和特异度，并与现有的PET成像报告基因分析进行比较。 这项工作将提供一个统一的报告基因系统，可以监测从高通量选择的单个活细胞到整个活体动物的PET基因表达。这样一个多功能的系统应该会在生物学中得到广泛的应用，从体内细胞转移、肿瘤转移、小动物疾病模型、转基因小鼠、小鼠药物筛选，到体内基因功能和调控研究。

DESCRIPTION (provided by applicant): Understanding gene function is a fundamental but still challenging task. It often involves monitoring gene transcription and regulation in both live cells and tissues in real time with reporter gene assays. A reporter gene that can work in both live cells and animals would be very valuable, but is currently unavailable. The overall goals of this research are to develop an integrated reporter gene system that is suitable for imaging gene expression in both single living cells and whole living animals including humans. An ampicillin resistance gene (encoding a bacterial enzyme, beta-lactamase) is an outstanding reporter for optical measurement of gene expression in single living mammalian tissue culture cells. To extend this reporter gene to whole living animals, it will require the development of new substrates. We will design and synthesize new substrates for imaging transgene expression with positron emission tomography (PET) in whole living mice. These new probes will be validated in living mice with tumor xenografts. Their sensitivity and specificity will be assessed and compared to the existing PET imaging reporter gene assays. This work will provide a unified reporter gene system that can monitor gene expression from single live cells undergoing high-throughput selection to whole living animals with PET. Such a versatile system should find wide applications in biology from in vivo cell trafficking, tumor metastasis, small animal disease models, transgenic mice, drug screenings in mice, to in vivo gene function and regulation study.