Chain reaction cloning using a bridging oligonucleotide and dna ligase

Abstract

Chain reaction cloning methods and reagents and kits for performing such methods are provided. Chain reaction cloning allows ligation of double-stranded DNA molecules by DNA ligases and bridging oligonucleotides. Double-stranded nucleic acid molecules are denatured into single-stranded molecules. The ends of the molecules are brought together by hybridization to a template. The template ensures that the two single-stranded nucleic acid molecules are aligned correctly. DNA ligase joins the two nucleic acid molecules into a single, larger, composite nucleic acid molecule. The nucleic acid molecules are subsequently denatured so that the composite molecule formed by the ligated nucleic acid molecules and the template cease to hybridize to each. Each composite molecule then serves as a template for orienting unligated, single-stranded nucleic acid molecules. After several cycles, composite nucleic acid molecules are generated from smaller nucleic acid molecules. A number of applications are disclosed for chain reaction cloning including site-specific ligation of DNA fragments generated by restriction enzyme digestion, DNAse digestion, chemical cleavage, enzymatic or chemical synthesis, and PCR amplification.