Plants, plasmids and possibilities — Methods permit functional gene studies in plants

Scientists also create modified plants to identify and characterize the functions of specific genes. The current issue of Cold Spring Harbor Protocols—released online today (www.cshprotocols.org)—includes a set of techniques for the creation of transgenic plants.

One of the protocols, freely available at http://www.cshprotocols.org/cgi/content/full/2006/30/pdb.prot4668, describes the use of a bacterium, Agrobacterium, to create transgenic Arabidopsis plants. Arabidopsis is used in many studies due to its short reproductive cycle, ease of cultivation, and close relatedness to economically important species such as broccoli and cauliflower. Agrobacterium contains a small chromosome—called the Ti plasmid—into which scientists can insert a gene of interest.

This ‘transgene’ is transferred to Arabidopsis through natural infection with Agrobacterium.

The highlighted article from CSH Protocols describes three techniques that encourage Agrobacterium to infect Arabidopsis plants: dipping an Arabidopsis flower directly into a solution containing Agrobacterium, mechanically forcing the Agrobacterium into the plant cells by applying vacuum, and simply spraying an Agrobacterium suspension onto the plants.