Interstrand Cross-Linking of Nucleic Acids: From History to Recent and Future Applications

Abstract

This chapter contains an elaborate overview of various methods that have been developed for interstrand cross-linking of nucleic acids. The existing cross-link methodologies can be subcategorized in different groups, each interesting depending on the requirements of the envisaged application. An endogenous or exogenous bifunctional compound can react with two different nucleophilic groups on the nucleobases, resulting in fast and high-yielding cross-linking. However, when site selectivity of the formed cross-link is desired, other approaches are required. Therefore, a series of methodologies are at hand where functionalities are introduced in oligonucleotide probes, which can be intrinsically reactive or can be triggered and activated at a selected time upon target recognition. In a third class, both strands are modified with orthogonal groups. After reaction of the introduced functionalities, a cross-link is formed at a specific and fixed position. The chapter ends with an overview of and outlook to present and future applications. It is thus shown that cross-linking agents can be exploited as useful therapeutic or diagnostic tools and have further proven their utility in the stabilization or structure elucidation of cross-linked systems aimed at studying and understanding the repair systems in a cell.