Development of Cell-Permeable Peptide Nucleic Acid

描述（由申请人提供）：最近，我们开发了一类新的肽核酸，称为GPNA，它很容易被人类体细胞和胚胎干细胞吸收，并特异性地将序列与DNA和RNA结合。与未修饰的PNA及其其他衍生物相比，与基因转录物的转录和翻译起始位点结合的GPNA引发了强烈的反义作用，具有异常低的细胞毒性。拟议的研究将探索这类特殊分子的范围，并建立对包括人类胚胎干细胞在内的多种细胞系控制细胞摄取、杂交和细胞毒性的因素和机制的基本理解。具体来说，我们的目标是在未来五年内实现四个具体目标。目的1 (Section D.1)：评估GPNA对人体细胞和胚胎干细胞的反义作用；目标2（章节D.2）：优化细胞摄取、杂交和细胞毒性。目的3（章节D.3）：确定GPNA摄取和细胞毒性的机制。目的4 (Section D.4)：确定GPNA调控基因表达的范围。

DESCRIPTION (provided by applicant): Recently we have developed a new class of peptide nucleic acid called GPNA that is readily taken up by both human somatic and embryonic stem cells, and binds sequence specifically to DNA and RNA. GPNA designed to bind to the transcription and translation start site of the gene transcript elicited potent antisense effect with unusually low cytotoxicity compared to the unmodified PNA and its other derivatives. The proposed research will explore the scope of this particular class of molecules and establish a basic understanding of the factors and mechanisms that control cellular uptake, hybridization and cytotoxicity over a wide range of cell lines, including human ES cells. Specifically, we aim to accomplish four specific objectives within the next five years. Aim 1 (Section D.1): Evaluate the antisense effects of GPNA with human somatic and ES cells; Aim 2 (Section D.2): Optimize cellular uptake, hybridization and cytotoxicity. Aim 3 (Section D.3): Determine the mechanism of GPNA uptake and cytotoxicity. And Aim 4 (Section D.4): Determine the scope of GPNA in regulating gene expression. The proposed study is crucial to the future design and development of nucleic acid mimics for a safe and effective use in animals and in humans. GPNA is, to the best of our knowledge, the first example of nucleic acid analogue taken up by human ES cells. This is intriguing because these primitive cells are extremely difficult to penetrate and are sensitive to the environmental cues. Human ES cells hold the key to understanding early human development that can neither be studied directly in utero nor fully understood with animals model, not to mention its enormous potential for regenerative medicine. Many fascinating questions concerning human ES cell proliferation, differentiation, cellular lifespan and so forth have not yet been addressed. Furthermore, recent evidence suggests that cancers may arise from stem cells. If this proves to be correct, it will alter the course of cancer treatment. Before we can begin to address these questions, an effective method must be developed to regulate gene expression in these and related cell types - this is the aim of our research.