[Cloning of single-stranded synthetic DNA]

The method for cloning a single-stranded synthetic DNA with the short complementary oligonucleotides, that form corresponding restriction sites, is proposed. The potency of the method is demonstrated by cloning a single-stranded polynucleotide A (93 nucleotide residues (n. r.] in plasmid vector pBR327. The polynucleotide A includes a leader structure of the human fibroblast interferon gene. Oligonucleotides (IV) (20 n. r.) and (VI) (16 n. r.) were taken as strengthening complements and to create the sticky ends for the restrictases HindIII and EcoRI. 72% of the obtained clones appeared to be hybrid. Four hybrid clones were analyzed, and three of them carried the desirable insertion. The primary structures of these insertions are confirmed by sequencing.