Junction, a term in telecommunications, refers to a device installed between cables, featuring certain insulation and sealing properties, enabling the continuous operation of two or more cables. In genetic engineering, it is a sequence that allows two DNA molecules or the ends of one DNA molecule to be paired and covalently linked by an enzyme. Currently, artificial hexamer junctions (containing a specific enzyme's切口) are commonly used, and multiple hexamer junctions can be connected to form a polymeric junction (polym junction).inker)。