Extracellular VirB5 Enhances T-DNA Transfer from Agrobacterium to the Host Plant
Figure 1
Agrobacterium cell growth, vir gene expression, attachment to host cells, and host defense response in the presence of exogenous VirB5.
(A) SDS PAGE analysis of purified VirB5. (B) Growth curve of Agrobacterium. Gray squares, no VirB5; black squares, +VirB5. (C) vir gene induction by acetosyringone. MU, Miller units. (D) Agrobacterium attachment to plant tissues. CFU, colony-forming units. All data represent average values of three independent experiments with indicated standard deviations. Results obtained in VirB5-treated samples were not statistically different from untreated controls (P-values>0.2). (E) RT-PCR analysis of induction of PR1 gene expression by treatment with salicylic acid. Lane 1, control; lane 2, +salicylic acid; lane 3, +VirB5; lane 4, +VirB5+salicylic acid. (E) RT-PCR analysis of induction of 4-CL1 gene expression by treatment with flagellin 22. Lane 1, control; lane 2, +flagellin 22; lane 3, +VirB5; lane 4, +VirB5+flagellin 22. Constitutively expressed ACTIN (ACT) was used as internal control (lower panels).