The PCT patent application “Transformation of Seaweed Utilizing Biolistic Gene Transfer to Spores”, invented by Prof. Qin Song, Associate Prof. Jiang Peng et al. from IOCAS, was authorized on Feb. 16, 2010 in USA (Patent No. US 7,663,026 B2).
This invention pertains to a new method for producing improved seaweed strains by genetic engineering. The significant innovation include the selection of seaweed spore as recipient for gene transfer, and the detection of foreign gene expression in generated plant through natural development process from spore.
For genetic engineering of higher plant, the regular protocol takes advantage of the totipotency of plant cell. That is, the differentiated tissue or cell were dedifferentiated firstly, to produce callus or protoplast, which were the final target for gene transfer, and the transgenic plant was obtained by re-differentiation and regeneration. However, there were difficulties for seaweed to adopt this protocol, because some species were hard to produce callus or protoplast, even it could, most are hard to regenerate, and others were never to detect the stable foreign gene expression in regenerated plants.
Alternatively, seaweeds always have many types of spore through whole life cycle, such as the female or male gametophytes of cultivated kelp Laminaria and Undaria generated from swimming spore, or conchospore, carpospore from economic red alga Porphyra. Especially, the techniques for sporangia induction, spore collection, culture and development regulation have well been set up, thus, the seaweed spore were ideal recipient for genetic transformation. The feasibility of seaweed spore-mediated transformation was firstly proved in Laminaria, and further confirmed in Undaria and Porphyra, suggesting that this protocol was common for seaweed.
China has the largest scale of seaweed cultivation around the world. Cultivated seaweed was important resource for healthy food and phycocolloids including agar, carrageenan and alginate. The patented technique for seaweed genetic transformation was expected to play important role in serving as a novel tool for algal basic research, and constructing genetically modified strain for new energy exploration and carbon fixation by seaweed. The spore-mediation pathway was of algal characteristics, and then important development for methodology of plant genetic engineering.