A comparison of virulence determinants in an octopine Ti plasmid, a nopaline Ti plasmid, and an Ri plasmid by complementation analysis of Agrobacterium tumefaciens mutants

Hooykaas, Paul J. J.; Mh, Hofker; Dulk-Ras, H. den; Schilperoort, R. A.

doi:10.1016/0147-619x(84)90026-x

Cited by 130 publications

(109 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1C). Besides, LBA2571 could not complement the virE2 transposon insertion mutant LBA1514 (Hooykaas et al, 1984) in extracellular complementation experiments (data not shown).…”

Section: Construction Of An a Tumefaciens Vire1 Deletion Strainmentioning

confidence: 99%

“…pSDM3005 contains the Bacillus subtilis sacR/B gene and a kanamycin resistance marker and does not replicate in A. tumefaciens to allow easy selection for double crossover events in A. tumefaciens. The sequence of pSDM3600 was confirmed by sequence analysis, and the plasmid was electroporated into LBA1100 (den Dulk-Ras and and LBA1010 (C58 with pTiB6; Hooykaas et al, 1984), and Km r colonies were tested for Suc sensitivity (sucr s ) in LC medium (lacking NaCL, but with 6% [w/v] Suc), indicating a single crossover event with the flanking regions of virE1. Km r /sucr s colonies were grown overnight in LC medium (lacking NaCl) to allow a second excisional recombination event, resulting in precise deletion of virE1 from the vir region.…”

Section: Bacterial Strainsmentioning

confidence: 99%

See 1 more Smart Citation

Recognition of the Agrobacterium tumefaciens VirE2 Translocation Signal by the VirB/D4 Transport System Does Not Require VirE1

et al. 2003

View full text Add to dashboard Cite

Agrobacterium tumefaciens uses a type IV secretion system to deliver a nucleoprotein complex and effector proteins directly into plant cells. The single-stranded DNA-binding protein VirE2, the F-box protein VirF and VirE3 are delivered into host cells via this VirB/D4 encoded translocation system. VirE1 functions as a chaperone of VirE2 by regulating its efficient translation and preventing VirE2-VirE2 aggregation in the bacterial cell. We analyzed whether the VirE1 chaperone is also essential for transport recognition of VirE2 by the VirB/D4 encoded type IV secretion system. In addition, we assayed whether translocation of VirF and VirE3, which also forms part of the virE operon, is affected by the absence of VirE1. We employed the earlier developed CRAFT (Cre recombinase Reporter Assay For Translocation) assay to detect transfer of Cre::Vir fusion proteins from A. tumefaciens into plants, monitored by stable reconstitution of a kanamycin resistance marker, and into yeast, screened by loss of the URA3 gene. We show that the C-terminal 50 amino acids of VirE2 and VirE3 are sufficient to mediate Cre translocation into host cells, confirming earlier indications of a C-terminal transport signal. This transfer was independent of the presence or absence of VirE1. Besides, the translocation efficiency of VirF is not altered in a virE1 mutant. The results unambiguously show that the VirE1 chaperone is not essential for the recognition of the VirE2 transport signal by the transport system and the subsequent translocation across the bacterial envelope into host cells.Agrobacterium tumefaciens causes crown gall disease on a wide range of plants by genetic transformation of host cells with a piece of its oncogenic plasmidborne transfer (T)-DNA (for most recent review, see Gelvin, 2003). The expression of the genes located on the T-DNA, which contain plant transcription and translation signals, results in overproduction of the plant hormones auxin and cytokinin and hence increased cell division and the tumor phenotype. A set of accessory virulence or effector proteins (encoded by the vir region on the tumor inducing [Ti] plasmid) is also transported into the transformed cells to confer full virulence. The host range is not confined to the plant kingdom, because A. tumefaciens can also transform yeast (Bundock et al., 1995), fungi (de Groot et al., 1998), and mammalian cells (Kunik et al., 2000).The translocated proteins of A. tumefaciens described to date include VirD2, VirE2, VirE3, and VirF. In the bacterium, VirD2 introduces a nick at the border sequences surrounding the T-DNA and by replacement synthesis a single-stranded (ss) DNA copy of the bottom strand is released. VirD2 acts as a pilot protein as it remains covalently attached to the 5Ј end of the T-strand during transport of the T-DNA into the host cell nucleus (Ward and Barnes, 1988). The ssDNA-binding protein VirE2 binds cooperatively to the T-strand and thereby protects it from degradation in the host cell (Rossi et al., 1996). Both VirD2 and VirE2 contain nucl...

show abstract

“…1C). Besides, LBA2571 could not complement the virE2 transposon insertion mutant LBA1514 (Hooykaas et al, 1984) in extracellular complementation experiments (data not shown).…”

Section: Construction Of An a Tumefaciens Vire1 Deletion Strainmentioning

confidence: 99%

Section: Bacterial Strainsmentioning

confidence: 99%

Recognition of the Agrobacterium tumefaciens VirE2 Translocation Signal by the VirB/D4 Transport System Does Not Require VirE1

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Host range has been shown to be determined by the type of Ti plasnnid present in the bacterium (24,31). Loci specific for hostrange have been mapped on the Ti plasmids jn the T-DNA region (3, 16) as well as outside the T-DNA (12,21,22).…”

mentioning

confidence: 99%

Virulence of Agrobacterium tumefaciens Strain A281 on Legumes

Hood¹,

Fraley²,

Chilton³

1987

Plant Physiol.

View full text Add to dashboard Cite

This study addresses the basis of host range on legumes of Agrobacterium tumefaciens strain A281, an LL-succinamopine strain. We tested virulence of T-DNA and vir region constructs from this tumor-inducing (Ti) plasmid with complementary Ti plasmid re,gions from heterologous nopaline and octopine strains.Agrobacterium tumefaciens is the etiologic agent of crown gall. Oncogenic strains ofA. tumefaciens harbor large plasmids, called Ti2 plasmids (for review, see Ref. 17). Part of the Ti plasmidthe T-DNA-is transferred to the plant where it is stably maintained in the nuclear DNA (4, 5). The T-DNA contains genes that are transcribed in the plant (4) encoding enzymes for opine synthesis (29) and phytohormone synthesis (1,2,27,30 described previously (20). In some instances, Agrobacterium was grown on AT minimal medium (11). Antibiotic concentrations were as follows: for Agrobacterium: kanamycin sulfate (Sigma), 50 ,g/ml; naladixic acid (Sigma), 25 ,g/ml; tetracycline hydrochloride (Calbiochem), 10 sg/ml; carbenicillin (or ampicillin) (Sigma), 50 ug/ml; for E coli: kanamycin sulfate, 50 gg/ml; tetracycline hydrochloride (Sigma), 25 gg/ml; carbenicillin ( Scoring of Tumors. Soybean and alfalfa tumors were scored at 1-week intervals for 5 weeks after inoculation. Tumor formation was scored according to the number of inoculation sites forming tumors, then expressed as a ratio to total sites inoculated (Table II). Photographic records were also kept. RESULTS

show abstract

“…The host factor VBF may be the key to understanding why A. tumefaciens strains lacking the virF gene can still induce tumors on some plant species (Hooykaas et al, 1984;Melchers et al, 1990;Jarchow et al, 1991;Regensburg-Tuïnk and Hooykaas, 1993). In such plants, A. tumefaciens may exploit a host VBF-like protein during infection as an alternative to VirF.…”

Section: Involvement Of a Host F-box Protein In A Tumefaciens Infectionmentioning

confidence: 99%

The Role of the Ubiquitin-Proteasome System in Agrobacterium tumefaciens-Mediated Genetic Transformation of Plants

Magori

Citovsky

2012

Plant Physiology

View full text Add to dashboard Cite

A comparison of virulence determinants in an octopine Ti plasmid, a nopaline Ti plasmid, and an Ri plasmid by complementation analysis of Agrobacterium tumefaciens mutants

Cited by 130 publications

References 35 publications

Recognition of the Agrobacterium tumefaciens VirE2 Translocation Signal by the VirB/D4 Transport System Does Not Require VirE1

Recognition of the Agrobacterium tumefaciens VirE2 Translocation Signal by the VirB/D4 Transport System Does Not Require VirE1

Virulence of Agrobacterium tumefaciens Strain A281 on Legumes

The Role of the Ubiquitin-Proteasome System in Agrobacterium tumefaciens-Mediated Genetic Transformation of Plants

Contact Info

Product

Resources

About