Production of transgenic plants by
use of co-integrated Ti plasmids
The soil bacterium
Agrobacterium
tumefaciens causes crown gall disease in plants by
transfering the T-DNA region
of a tumor-inducing (Ti) plasmid into host cells (Top). The T-DNA region of the Ti plasmid can
be genetically engineered to contain an antiobiotic resistance gene (kanR) as well as a foreign gene
of interest (inset diagram). Infection of plant cells in culture with
bacteria containing this co-integrated
Ti plasmid
allow the foreign DNA to
be transfered into the host cell. Integration of the foreign DNA
disrupts tumor formation, and only those plant cells with the kanR gene will grow in culture containing
antibiotic. Plants are easily
regenerated from cultured cells (calluses):
the adult transgenic plant expresses the foreign gene.
Figure modified after
Griffiths et al. 2002; text material
©2008 by Steven M. Carr