PROCESS FOR THE DEFINITE CROSS-LINKING OF DOUBLE HELIX DNA FRAGMENTS BY MEANS OF A LINKAGE DNA AS WELL AS OLIGONUCLEOTIDES USED AS LINKAGE DNA

摘要

Process for the definite cross-linking of DNA fragments by means of cohesive ends by replacing a first fragment by a linkage DNA, dividing the obtained DNA in the region of the linkage sequence during the formation of the cohesive end and cross-linking the obtained DNA having the cohesive end with a second DNA fragment, the cohesive ends of the first end of the second DNA fragment being complementary. As linkage DNA, an oligonucleotide is used which has the formula R1 - (X)¿n - R?2 wherein R?1 and R2¿ represent, reading from left to right, identical tetranucleotide sequences, in themselves complementary, having the formula (II), or R1 is a pentanucleotide sequence having the formula (III) and R2 is a pentadesoxynucleotide sequence having the formula (IV), the central nucleotides being complementary sequences of R?1 and R2¿ groups being identical, or else R1 representing a tetranucleotide or pentanucleotide sequence which is not complementary in itself or an hexanucleotide sequence having the formula (V), (VI) or (VII) and R2 a complementary nucleotide sequence enantiomorphous of R1 and of the same length. X is a short intermediary compound having the form of an oligonucleotide comprising from 2 to 30 nucleotide units.