Why molecular farming?
Molecular Farming is the use of plants or plant cells to produce high-value compounds such as medicines, diagnostic proteins and/or industrial enzymes. Molecular Farming combines biotechnology and agriculture to produce new goods for the world.
Plants have distinct advantages over microbial and animal cell culture systems. They have a reduced risk of mammalian viral contaminants, oncogenes and bacterial toxins. They can also produce correctly folded proteins and assemble multimeric proteins such as antibodies. In addition, glycosylation pattern of plants is similar to that of humans. Especially, plants’ ability to perform complex post-translational modification is particularly important because it allows the production of complicated glycoproteins in correctly glycosylated which is crucial in the bioactivity and stability of certain proteins. Although good yields of single polypeptide proteins can be achieved in a relatively short time using bacterial or lower eukaryotic expression systems, these systems cannot be applied to produce proteins requiring precise post-translational modification or the assembly of multimeric subunits for their biological activity. Therefore, plants are advantageous to produce protein of interest is multimeric, and if it requires precise post-translational modification.
Why rice expression system?
The rice cell suspension culture system using the rice-amylase 3D (RAmy3D) promoter has become increasingly popular as a machinery for the production of pharmaceutical and industrial proteins. The RAmy3D promoter and terminator function together as a powerful system for the production of recombinant proteins. The RAmy3D promoter with a signal peptide system overcomes the current shortcomings associated with a low productivity and slow growth of plant cells during sugar starvation conditions under the control of the RAmy3D promoter.
Rice is a well-studied model plant whose genome has been decoded, and its transformation technology has been very well developed. As the third most popularly produced crop in the world, rice is also considered to be hypoallergenic and is considered an excellent host for protein production even for human application.
Rice is probably the most suitable host for producing recombinant protein due to its competitive yield of recombinant proteins compared to other plant expression systems.
Why plant cell suspension culture?
Plant cell suspension cultures are regarded as the most suitable for industrial applications in plant-based production of valuable materials. They have been used in production of a large number of therapeutic proteins, and the systems upscaled into bioreactors have been utilized commercially. Plant cell suspension cultures suggest the advantages such as easy control of culture environment, fast cell growth, and potential to be upscaled into bioreactors. The most important advantage of using plant cell culture over whole plants in the production of valuable materials is that the procedures for the isolation and purification of the products are much simpler, particularly by utilizing a signal peptide, recombinant proteins produced will be secreted out of the cell into the culture medium, eliminating the need to extract the proteins through cell lysis.