Various expression-augmenting DNA elements benefit from STAR-Select, a novel high stringency selection system for protein expression.

The creation of highly productive mammalian cell lines often requires the screening of large numbers of clones, and even then expression levels are often low. Previously, we identified DNA elements, anti-repressor or STAR elements, that increase protein expression levels. These positive effects of STAR elements are most apparent when stable clones are established under high selection stringency.