Characterization of competent cells and early events of Agrobacterium-mediated genetic transformation in Arabidopsis thaliana

摘要: The insertion of foreign DNA in plants occurs through a complex interaction between Agrobacteria and host plant cells. marker gene β-glucuronidase Escherichia coli cytological methods were used to characterize competent cells for Agrobacterium-mediated transformation, study early cellular events identify the potential host-cell barriers that limit transformation Arabidopsis thaliana L. Heynh. In cotyledon leaf explants, mesophyll dedifferentiating, process induced by wounding and-or phytohormones. located either at cut surface or within explant after phytohormone pretreatment. root present dedifferentiating pericycle, produced only Irrespective their origin, small, isodiametric with thin primary cell walls, small multiple vacuoles, prominent nuclei dense cytoplasm. both histological enumeration assays showed number putatively was increased preculture treatment, indicating activation division following insufficient without treatment. Exposure explants 48 h A. tumefaciens no characteristic stress response nor any gradual loss viability death. However, cell, association polysaccharide wall bacterial filament frequently observed, required polysaccharide-to-polysaccharide contact. Flow cytofluorometry analysis abundant not (an state exhibiting an increase nuclear protein) but also proliferation (which tissue occurred many ploidy levels). Noncompetent could be made appropriate treatments before infection: this should aid critical steps procedures facilitate developing new strategies transform recalcitrant plants.