Recombinant DNA is a DNA molecule formed by joining sequence segments into a new genetic arrangement. Complementary ends can align the constituent fragments, and polymerase and ligase activities complete a continuous DNA backbone [1]. Constructs can combine promoters, coding sequences, and termination elements into single or multiple expression units, with the orientation and boundaries of each segment specified during assembly [2]. Restriction-based joining uses recognition and cleavage properties that generate compatible fragment ends; controlled methylation can provide additional specificity for cleavage and ligation [3]. Hierarchical assembly connects intermediate constructs into larger molecules while preserving the intended sequence organization [4]. The resulting molecule carries the combined nucleotide information, including the designed junctions and any replication or selection elements included in the construct [5].
CRISPR and Genetic Engineering·Molecular Biology·Biochemistry, Genetics and Molecular Biology·Life Sciences