The invention provides a recombinant vector comprising a DNA segment having a synthetic origin of DNA synthesis that binds EBNA-1 and is capable of initiating DNA synthesis of sequences linked to the synthetic origin of DNA synthesis and maintaining the linked sequences when in the presence of EBNA-1. The synthetic origin of DNA synthesis comprises at least two binding sites for EBNA-1, wherein the two EBNA-1 binding sites are flanked by at least two half-binding sites for TRF2 or at least two binding sites for a protein that enhances the affinity of EBNA-1 for the synthetic origin of DNA synthesis. Further provided are host cells with the vector and methods of using the vector, for instance, ex vivo or in vivo.