Plant Proteins That Interact with VirB2, the Agrobacterium tumefaciens Pilin Protein, Mediate Plant TransformationW⃞
AUTOR(ES)
Hwang, Hau-Hsuan
FONTE
American Society of Plant Biologists
RESUMO
Agrobacterium tumefaciens uses a type IV secretion system (T4SS) to transfer T-DNA and virulence proteins to plants. The T4SS is composed of two major structural components: the T-pilus and a membrane-associated complex that is responsible for translocating substrates across both bacterial membranes. VirB2 protein is the major component of the T-pilus. We used the C-terminal–processed portion of VirB2 protein as a bait to screen an Arabidopsis thaliana cDNA library for proteins that interact with VirB2 in yeast. We identified three related plant proteins, VirB2-interacting protein (BTI) 1 (BTI1), BTI2, and BTI3 with unknown functions, and a membrane-associated GTPase, AtRAB8. The three BTI proteins also interacted with VirB2 in vitro. Preincubation of Agrobacterium with GST-BTI1 protein decreased the transformation efficiency of Arabidopsis suspension cells by Agrobacterium. Transgenic BTI and AtRAB8 antisense and RNA interference Arabidopsis plants are less susceptible to transformation by Agrobacterium than are wild-type plants. The level of BTI1 protein is transiently increased immediately after Agrobacterium infection. In addition, overexpression of BTI1 protein in transgenic Arabidopsis results in plants that are hypersusceptible to Agrobacterium-mediated transformation. Confocal microscopic data indicate that GFP-BTI proteins preferentially localize to the periphery of root cells in transgenic Arabidopsis plants, suggesting that BTI proteins may contact the Agrobacterium T-pilus. We propose that the three BTI proteins and AtRAB8 are involved in the initial interaction of Agrobacterium with plant cells.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=527204Documentos Relacionados
- Vir Proteins Stabilize VirB5 and Mediate Its Association with the T Pilus of Agrobacterium tumefaciens
- VirB2 is a processed pilin-like protein encoded by the Agrobacterium tumefaciens Ti plasmid.
- The Agrobacterium T-DNA Transport Pore Proteins VirB8, VirB9, and VirB10 Interact with One Another
- Genetic complementation analysis of the Agrobacterium tumefaciens virB operon: virB2 through virB11 are essential virulence genes.
- Suppression of mutant phenotypes of the Agrobacterium tumefaciens VirB11 ATPase by overproduction of VirB proteins.