Patent ID: 10017786

Abstract:
Provided herein are methods for stable integration and/or expression of one or more recombinant polynucleotides in a host cell. The recombinant polynucleotides are typically integrated into the host genome at some native chromosomal integration sites. The integration can be mediated by homologous recombination or by using a hybrid recombinase targeting the specific chromosomal locations. The native chromosomal integration sites in the host cells, which support stable integration and strong transcription activities of foreign genes, are present within or adjacent to specific genes in the CHO genome, the ankyrin 2 gene (Ank2), cleavage and polydenylation specific factor 4 gene (Cpsf4), C-Mos gene, and Nephrocystin-1/Mal gene. Also provided are methods and nucleic acid molecules for inserting site-specific recombination sequences (chromosomal landing pads) into these specific chromosomal locations, engineered host cells containing chromosomal landing pads, methods and compositions (e.g., kits) therefore.