Department of Biology, Indiana University, Bloomington, Indiana 47405.
Plant Physiol. 1992 Mar;98(3):979-83. doi: 10.1104/pp.98.3.979.
We have examined the response of the hormone-resistant mutants axr1 and axr2 of Arabidopsis thaliana to inoculation by Agrobacterium tumefaciens and Agrobacterium rhizogenes. Our results indicate that recessive mutations in the axr1 gene affect the frequency of tumor formation after inoculation with either Agrobacterium strain. In addition, tumors produced on axr1 plants were smaller than those growing on wild-type plants. These results indicate that the product of the AXR1 gene is important for both crown gall and hairy root tumor formation. In contrast, the dominant axr2 mutation has a more severe effect on the development of crown gall tumors than on hairy root tumors. Crown gall tumors produced on axr2 plants had a different morphology than wild-type tumors and did not grow when they were removed from the explant. In contrast, a large number of hairy root tumors were produced on wild-type and axr2 plants, and both types of tumors grew when they were removed from the explant. Like the roots of axr2 plants, roots produced on axr2 explants lacked root hairs.
我们研究了拟南芥激素抗性突变体 axr1 和 axr2 对根癌农杆菌和发根农杆菌接种的反应。我们的结果表明，axr1 基因的隐性突变影响了两种农杆菌菌株接种后肿瘤形成的频率。此外，axr1 植株上产生的肿瘤比野生型植株上的肿瘤小。这些结果表明，AXR1 基因的产物对冠瘿瘤和发状根肿瘤的形成都很重要。相比之下，显性 axr2 突变对冠瘿瘤的发育比对发状根肿瘤的发育有更严重的影响。axr2 植株上产生的冠瘿瘤与野生型肿瘤的形态不同，从外植体上移除后不再生长。相比之下，大量的发状根肿瘤在野生型和 axr2 植株上产生，并且当从外植体上移除时，两种类型的肿瘤都生长。与 axr2 植株的根一样，axr2 外植体上产生的根缺乏根毛。
