Analyzing genetic factors involved in recombinant protein expression enhancement

Understanding the genetic factors that promote recombinant protein accumulation in transgenic plants will provide insightful strategies for protein biofactory efficiency. Through combining biological and bioinformatics analysis, our work is to determine genetic and biological factors affecting increased protein accumulation of a bacterial cellulase enzyme in transgenic maize. Microarray experiments were performed on maize near-isogenic lines that exhibit high and low accumulation of the enzyme expressed from a transgene in seeds. Through microarray data analysis, two thousand three hundred thirteen genes were identified which exhibited at least a 1.5-fold change in expression level. One hundred sixty-one genes from the data set are shown to be statistically valid. Of these, eighty-two genes are up-regulated while seventy-nine genes are down-regulated. Preliminary functional analysis of the genes was conducted and several pathways of biological importance were tentatively identified. These genes code for four categories of proteins: known proteins, zein proteins, putative proteins and unknown proteins. Further functional clustering and annotation analysis for these genes will help construct and define networks of interaction as well as predict important metabolic pathways to understand the controlling mechanisms that lead to the hyper-accumulation phenomenon.