Identification of a novel endogenous regulatory element in Chinese hamster ovary cells by promoter trap.

The objective of this study was to identify and isolate endogenous promoters in Chinese hamster ovary (CHO) cells using a promoter trap approach. A promoter-less vector harboring a green fluorescent protein (GFP)-hygromycin resistance gene cassette was designed and transfected into CHO cells. Putative promoters were identified by selecting for GFP(+) clones under hygromycin selection.