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. 1989 Dec;86(23):9154–9158. doi: 10.1073/pnas.86.23.9154

Covalently bound VirD2 protein of Agrobacterium tumefaciens protects the T-DNA from exonucleolytic degradation.

F Dürrenberger 1, A Crameri 1, B Hohn 1, Z Koukolíková-Nicola 1
PMCID: PMC298452  PMID: 2556703

Abstract

We show that upon induction of Agrobacterium tumefaciens, free linear double-stranded T-DNA molecules as well as the previously described T-strands are generated from the Ti plasmid. A majority of these molecules are bound to a protein. We show that this protein is the product of the virulence gene virD2. This protein was found to be attached to the 5' terminus of processed T-DNA at the right border and to the rest of the Ti plasmid at the left border. The protein remnant after Pronase digestion rendered the right end of the double-stranded T-DNA resistant to 5'----3' exonucleolytic attack in vitro. The protein-DNA association was resistant to SDS, mercaptoethanol, mild alkali, piperidine, and hydroxylamine, indicating that it involves a covalent linkage. The possible involvement of this T-DNA-protein complex in replication, transduction to the plant, nuclear targeting, and integration into the plant nuclear DNA is discussed.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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