HMG2 promoter expression system and post-harvest production of gene products in plants and plant cell cultures
The invention relates in part to plant HMG2 HMGR genes and in part to the ''post-harvest'' production method of producing gene product of interest in plant tissues and cultures. The HMG2 promoter elements are responsive to pathogen-infection, pest-infestation, wounding, or elicitor or chemical treatments. The HMG2 elements are also active in specialized tissues of the plant including pollen and mature fruits. HMG2 promoter elements and HMG2-derived promoters can be advantageously used to drive the expression of disease and pest resistance genes, whereby transgenic plants having such gene constructs would be resistant to the targeted disease and pest. In particular, the HMG2 gene expression system can be utilized in developing nematode resistant plants. The post-harvest production method of the invention utilizes plant tissues and cell cultures of plants or plant cells engineered with a expression construct comprising an inducible promoter, such as the HMG2 promoter, operably linked to a gene of interest. Production of the desired gene product is obtained by harvesting, followed by inducing and processing the harvested tissue or culture. The post-harvest production method may be advantageously used to produce direct or indirect gene products that are labile, volatile, toxic, hazardous, etc.