Microprojectile bombardment

Some agronomically important plant species (e. g. soybean and most cereal grains) are recalcitrant to Agrobacterium transformation, and a biolistic method (microprojectile bombardment) is frequently used for these plants [47]. DNA coated on micron-sized gold particles is propelled into plant cells using compressed helium gas... 

Hibbard, J.M. etal. (1998). Transient expression of green fluorescent protein in various plastid types following microprojectile bombardment. Plant J. 16 627-632. 

Fitzpatrick-McElligott, S. (1992). Gene transfer to tumor-infiltrating lymphocytes and other mammalian cells by microprojectile bombardment. Bio/Technology 10,1036 1040. 

Revertant of no-active RuBisCO tobacco mutant, Sp25, obtained by chloroplast transformation method using microprojectile bombardment... 

Zelenin, A.V. et al. Transfer of foreign DNA into the cells of developing mouse embryos by microprojectile bombardment, PEBS Lett., 315,29,1993. 

Biolistics involves bombarding plant cells with tiny (4- am) microprojectiles made of gold or tungsten. These microprojectiles are coated with DNA and are propelled at high velocity from a particle gun or gene gun into plant tissue or cells. In this method, the projectile penetrates the cell wall and carries the transgene into the cell nucleus. 

Fig. 7.2. Diagram of the PDS-1000/He, a stationary particle bombardment machine that is connected to a helium gas container. Controlled by adjustable valves, the gas stream (He) terminates in an acceleration tube, which is mounted on the top of a target chamber. This chamber is closed by a door and set under vacuum shortly before bombardment. When gas flows into the acceleration tube, the rupture disc bursts releasing the shock wave into the lower part of the tube. The gas pressure then accelerates the macrocarrier sheet containing the microprojectiles on its lower surface. The net-like stopping screen holds the macrocarrier sheet back and serves to block the shock wave, while the microprojectiles slip through the pores of the grid and continue on towards their final target.

The most effective means of transforming plant cells is through the use of "gene guns," or bombardment-mediated transformation. DNA is coated onto 1- p, m-diameter tungsten pellets, and these microprojectiles are fired at the target... 

Nonviral gene transfer systems are based on a variety of technologies that employ physical/chemical means to deliver genes [6], These technologies include direct plasmid injection, bombardment with DNA coated microprojectiles, and DNA complexed with liposomes or polymers. Some nonviral transfection techniques are too inefficient (e.g., coprecipitation of DNA with calcium phosphate [7], DNA complexed with diethylaminoethyl (DEAE)-dextran [8], electroporation [9]), or laborious (e.g., microinjection of DNA [ 10 ]) for clinical use. Only those gene delivery systems (viral and nonviral) with potential for clinical application are discussed in this chapter. The main features of these technologies (Table 18.3) are described and specific examples of their applications highlighted. 

Gene transformation has been demonstrated in black spmce using Agrobacterium-msdoaXeA, microprojectile particle bombardment, and electroporation techniques (KUmaszewska et al, 2003 ... 

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