Stable incorporation of plasmid DNA into higher plant cells: the molecular basis of crown gall tumorigenesis

  title={Stable incorporation of plasmid DNA into higher plant cells: the molecular basis of crown gall tumorigenesis},
  author={M. D. Chilton and Martin H. Drummond and Donald J. Merlo and Daniela Sciaky and Alice L. Montoya and Milton Paul Gordon and Eugene W. Nester},

Tumor DNA structure in plant cells transformed by A. tumefaciens.

Crown gall tumors are induced in plants by infection with the soil bacterium Agrobacterium tumefaciens. Because the tumor induction involves transfer of a portion of the tumor-inducing (Ti) plasmid

T-DNA of a crown gall teratoma is covalently joined to host plant DNA

The isolation by molecular cloning of a ‘border fragment’ T- DNA and flanking plant DNA from the crown gall teratoma BT37 is reported and it is shown that T-DNA is covalently joined to a repeated DNA element of the tobacco nuclear genome.

DNA from Ti plasmid present in nucleus and absent from plastids of crown gall plant cells

Evidence is presented for the absence of T-DNA from mitochondria and chloroplasts, and results clearly show its presence within the nucleus.

Foreign DNA sequences in crown gall teratomas and their fate during the loss of the tumorous traits

The correlation between the presence of foreign DNA and the tumor phenotype indicates that the continued presence of T-DNA is required for the maintenance of the tumorous state.

Ti-Plasmids: Genetic Engineering of Plants

The interaction between A. tumefaciens and plants can be seen as a special parasitic relationship which benefits the bacteria.

The Use of Ti-Plasmids for the Genetic Engineering of Plants

The interaction between these bacteria and plants can be seen as a special parasitic relationship which benefits the bacteria, and opines can be utilized by Agrobacterium tumefaciens selectively as sources for carbon, nitrogen, and energy.



Agrobacterium tumefaciens DNA and PS8 bacteriophage DNA not detected in crown gall tumors.

Renaturation kinetics of labeled Agrobacterium tumefaciens DNA are not influenced by addition of 10(4)-fold excess of crown gall tumor DNA, and PS8 bacteriophage DNA is not detected in crownGall tumor DNA under conditions that allow detection of 0.0007-0.001% added phage DNA.

Attempts to Detect Agrobacterium tumefaciens DNA in Crown-Gall Tumor Tissue.

The data indicate that tumor, but not healthy tissue DNA preparations contain some factor or factors (not DNA) which accelerate the reannealing of bacterial DNA.

The presence of Agrobacterium tumefaciens plasmid DNA in crown gall tumour cells.

SUMMARY: DNA hybridization studies indicate the presence of DNA complementary to Agrobacterium tumefaciens plasmid in bacterium-free crown gall tumour cells. The amount of this DNA is estimated to be

Plasmid required for virulence of Agrobacterium tumefaciens

Findings establish unequivocally that the large plasmid determines virulence in Agrobacterium tumefaciens strain C-58.

RP4 promotion of transfer of a large Agrobacterium plasmid which confers virulence.

Results indicate that virulence and the ability to degrade octopine are plasmid-borne traits in A. tumefaciens strains 15955 and A6, and extend the evidence that large plasmids in A.'s tumfaciens are vectors of virulence genes.

Evidence for diverse types of large plasmids in tumor-inducing strains of Agrobacterium

Plasmid homology studies for crown gall tumorigenesis is considered and two genetically distinct groups of plasmids can be identified: one closely related to the plasmid of A. tumefaciens A6, an octopine-utilizing strain, and the other closelyrelated to the Plasmodium C-58, a nopaline- utilizing strain.

Acquisition of tumour-inducing ability by non-oncogenic agrobacteria as a result of plasmid transfer

Besides providing further evidence for the hypothesis that plasmid genes carry the genetic information for the tumour-inducing ability of Agrobacterium, the system offers the possibility of studying the genetics and functions of the plasmids.