Modulation of the Properties of Nucleic Acids through Structural Modifications

核酸对许多基本的生物过程是至关重要的。它们携带遗传信息，并通过复制、转录和翻译传递这些信息。这些分子也因其在许多细胞过程中的调节作用而被公认。这一提议旨在将独特的结构部分引入核酸，从而赋予这些分子性质，从而进一步加深我们对基本生物学过程的了解。在这方面，将研究三种化学方法。首先，将探索一种代谢性标记核酸的方法。这一化学是基于四嗪和应变烯烃之间的反电子需求Diels-Alder反应。有人提出，应变的烯烃部分将被结合到核苷中，然后以酶的方式结合到核酸中。在这种结合后，将加入共价连接到BODIPY荧光团(以四嗪-BODIPY共轭形式的非荧光)的四嗪，其中发生反向电子需求Diels-Alder反应以恢复荧光。由于这种反应通常非常快，这种化学反应实际上将允许实时跟踪涉及核酸的细胞过程，而且重要的是，具有最少的荧光背景。第二,

Nucleic acids are crucial for many fundamental biological processes. They carry genetic information, and transmit it through replication, transcription and translation. These molecules are also recognized for their regulatory roles in many cellular processes. This proposal aims at approaches to introduce unique structural moieties into nucleic acids and consequently, confer properties to these molecules that will further our knowledge on the fundamental biological processes. In this regard, three chemical methods will be investigated. First, a methodology to metabolically label nucleic acids will be explored. This chemistry is based on the inverse Electron Demand Diels-Alder reaction between tetrazine and strained alkenes. It is proposed that a strained alkene moiety will be incorporated into nucleosides and subsequently, incorporated into nucleic acids enzymatically. Upon this incorporation, tetrazine that is covalently linked to a BODIPY fluorophore (non-fluorescent in the form of tetrazine-BODIPY conjugate) will be added, where an inverse Electron Demand Diels-Alder reaction takes place to restore the fluorescence. As such reactions are typically very fast, this chemistry will virtually allow for real-time tracking of cellular processes involving nucleic acids, and importantly, with minimal fluorescent background. Second,