title: Identification of T-DNA tagged Arabidopsis mutants that are resistant to transformation by Agrobacterium.
abstract: We have identified T-DNA tagged Arabidopsis mutants that are resistant to transformation by Agrobacterium tumefaciens (rat mutants). These mutants are highly recalcitrant to the induction of both crown gall tumors and phosphinothricin-resistant calli. The results of transient GUS (beta-glucuronidase) assays suggest that some of these mutants are blocked at an early step in the Agrobacterium-mediated transformation process, whereas others are blocked at a step subsequent to translocation of T-DNA into the nucleus. Attachment of Agrobacterium to roots of the mutants rat1 and rat3 was decreased under various incubation conditions. In most mutants, the transformation-deficient phenotype co-segregated with the kanamycin resistance encoded by the mutagenizing T-DNA. In crosses with susceptible wild-type plants, the resistance phenotype of many of these mutants segregated either as a semi-dominant or dominant trait.
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics* / Q000502:physiology; D017360:Arabidopsis / Q000235:genetics* / Q000382:microbiology*; D001422:Bacterial Adhesion; D003433:Crosses, Genetic; D004269:DNA, Bacterial / Q000235:genetics*; D017343:Genes, Plant; D009154:Mutation; D018517:Plant Roots / Q000382:microbiology; D014170:Transformation, Genetic