SIMPLE GENERATION AND PROPERTIES OF HYDRAZONE-DERIVED INTERSTRAND DNA CROSS-LINKS

Interstrand DNA cross-links prevent DNA strand separation that is required for replication and transcription processes; this blockage can lead to cell cycle arrest and apoptosis. DNA cross-link repair is complex and not well understood, partly because of the lack of structurally well-defined cross-links and simple, efficient preparation methods. Here we present the formation and properties of a hydrazone-derived cross-linked formed via the reaction of an aldehyde residue of an abasic site (Ap) and a non-natural nucleobase N4-aminocytidine (dC*). We generated the Ap-dC* cross-link in high yields using simple benchtop methods with commercially available materials. We observe that the Ap-dC* cross-link is stable in various conditions, it is not highly distorted, and can block DNA processing enzymes. Additionally, the Ap-dC* cross-link can dissociate and reconstruct over multiple heating-cooling cycles.