Expression Profiling Analysis of Sodium Butyrate-Induced Chinese Hamster Ovary Cells in Defined Medium

Abstract

The production of recombinant protein for biopharmaceutical application typically requires vast numbers of cells, and agents that induce expression of the desired product to even higher levels. A typical strategy employed by the biotech industry is to express the protein of interest in Chinese Hamster Ovary (CHO) cells stably transfected with the gene. Where even higher levels of expression are desired, inducing agents such as sodium butyrate or valeric acid are added to the media. Current research suggests that these chemicals increase expression by blocking deacetylation of histone proteins bound to DNA. This has the effect of relaxing DNA structure, and allowing greater access to the transcription machinery. Thus, higher levels of mRNA are achieved. However, these agents have the ultimate effect of blocking cell proliferation, and eventually inducing apoptosis in treated cells. We have undertaken an expression profiling approach to identify the genes up and down-regulated in induction conditions.