Thermally reversible and irreversible interstrand photocrosslinking of 5-chloro-2′-deoxy-4-thiouridine modified DNA oligonucleotides

We describe highly efficient interstrand photocrosslinking of a DNA duplex containing 5-chloro-2 '-deoxy-4-thiouridine (ClSdU) in one strand, proceeding via a two-step photochemical cascade, involving the formation of a thermally reversible crosslink between ClSdU and thymidine in the target strand and its subsequent conversion to a thermally stable fluorescent crosslink. These results show that ClSdU has great potential to be a valuable DNA photo-crosslinking reagent for chemical biology applications.

Automated summary

The study demonstrates a highly efficient DNA duplex interstrand photocrosslinking method using ClSdU, which forms a reversible crosslink with thymine in the target strand and converts to a stable fluorescent crosslink. The results indicate the great potential of ClSdU as a valuable DNA photo-crosslinking reagent for chemical biology applications.