title: Fundamental discoveries and simple recombination between circular plasmid DNAs led to widespread use of Agrobacterium tumefaciens as a generalized vector for plant genetic engineering.
abstract: Fundamental research aimed to determine the limits of the Agrobacterium transfer DNA (T-DNA) element that stably inserted into plant nuclear DNA to cause crown gall tumor formation. The T-DNA borders were discovered to be exceedingly precise, revealing that T-DNA insertion into the plant genome was reproducible and exact. Deletion of the internal regions of the T-DNA, to remove the tumor forming genes, while retaining the T-DNA borders, resulted again in efficient DNA transfer to plant cells, but now such cells were capable of completely normal growth and differentiation. Thus, the internal region of the T-DNA was not needed for DNA transfer, and one could envisage insertion of any DNA of interest in between the T-DNA borders. Thus began plant genetic engineering.
authors.affiliation: Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA. zambrysk@berkeley.edu.
authors.forename: Patricia
authors.initials: P
authors.lastname: Zambryski
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics*; D002467:Cell Nucleus / Q000378:metabolism; D004270:DNA, Circular / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics; D018014:Gene Transfer Techniques; D005818:Genetic Engineering / Q000266:history* / Q000379:methods; D005822:Genetic Vectors; D018745:Genome, Plant; D049673:History, 20th Century; D010944:Plants / Q000235:genetics; D030821:Plants, Genetically Modified; D010957:Plasmids / Q000235:genetics*; D011995:Recombination, Genetic
chemical_list: D004270:DNA, Circular; D018744:DNA, Plant