Oligodeoxynucleotides with Extended 3'- and 5'-Homologous Internucleotide Linkages.
作者:T. Kofoed、P. B. Rasmussen、P. Valentin-Hansen、E. B. Pedersen、Kari Rissanen、Wenjun Shi、Stenbjörn Styring、Cecilia Tommos、Kurt Warncke、Bryan R. Wood
DOI:10.3891/acta.chem.scand.51-0318
日期:——
3'-Deoxy-3'-C-(hydroxymethyl)thymidine (3'-DHMT) and 5'-deoxy-5'-C-(hydroxymethyl)thymidine (5'-DHMT) have been prepared and used for the synthesis of novel oligodeoxynucleotides containing extended internucleotide linkages. Enzymatic stability toward exonuclease III degradation was studied and hybridization properties were tested, The extended 3'-homologous DNA causes complete cessation of exonuclease III degradation while the extended 5'-homologous DNA shows only same decrease in degradation. Duplexes having extended internucleotide linkages show a minor decrease in hybridization stability. Tripler formation with 20-mer duplexes at pH 5.5 and high salt concentration gave almost no decrease in binding affinity when compared with unmodified tripler formation. UV experiments were also performed with oligodeoxynucleotides containing hairpin structures and bulged bases, Extended linkages in the oligodeoxynucleotides gave a small increase in T-m with sequences containing a loop, but no change or only a small decrease was observed when an extra thymidine nucleotide was incorporated in the complementary strand.