Estramareix C, Ratet P, Boulanger F, Richaud F
Plasmid. 1986 May;15(3):245-7. doi: 10.1016/0147-619x(86)90043-0.
Agrobacterium rhizogenes induces root formation at the site of inoculation in plants and inserts fragments of its Ri plasmid into the plant nuclear DNA. The transferred region (T-DNA) of the Ri plasmid of the A. rhizogenes strain A4 is made of two fragments, namely TL and TR; the latter harbors a sequence homology with the tms loci (responsible for auxin synthesis) of A. tumefaciens. On Daucus carota slices, single insertion mutations on the TL region of A. rhizogenes do not confer a mutant phenotype while an insertion-deletion in the TR region do confer a Basatt phenotype. Six double mutants with a single insertion in the TL region and the same deletion-insertion of the TR region were constructed. Three of these double mutants were avirulent on D. carota which indicates that in A. rhizogenes A4 the TL and the TR regions cooperate to confer a full infectious phenotype.
发根农杆菌能在植物接种部位诱导根的形成，并将其Ri质粒片段插入植物核DNA中。发根农杆菌A4菌株的Ri质粒转移区域（T-DNA）由两个片段组成，即TL和TR；后者与根癌农杆菌的tms位点（负责生长素合成）具有序列同源性。在胡萝卜切片上，发根农杆菌TL区域的单插入突变不会赋予突变表型，而TR区域的插入-缺失则会赋予Basatt表型。构建了六个在TL区域有单插入且TR区域有相同缺失-插入的双突变体。其中三个双突变体对胡萝卜无毒，这表明在发根农杆菌A4中，TL和TR区域共同作用以赋予完全感染表型。
