Abstract:

The system using plants as hosts to express foreign proteins is called molecular farming. The production of foreign proteins in plants via Agrobacterium tumefaciens-mediated transformation has the advantages of high efficiency, safety and low cost. Especially, protein post-translational modification in plants can make up for the defects of the prokaryotic expression system. In this review, we firstly introduce advances in tobacco leaf transient expression or rice endosperm specific expression, especially some typical examples of producing pharmaceutical proteins, medical compounds, and vaccines in molecular farming. In terms of optimizing bioreactors and improving expression efficiency, we then focus the regulation in protein post-translation, including the role of protease inhibitors, and the effects of glycosylation modification processes, and molecular chaperones co-expression on the expressions of foreign proteins. Finally, based on the foreign proteins accumulation in the endoplasmic reticulum（ER）would induce stress to ER, we propose the feasibility of increasing expression efficiency of foreign proteins by optimizing the ER environment.

Key words: plant bioreactor, molecular farming, transient expression in tobacco leaves, rice endosperm bioreactors, ER environment optimization