Agrobacterium tumefaciens T-DNA gene 6b stimulates rol-induced root formation, permits growth at high auxin concentrations and increases root size.

摘要: All Agrobacterium tumefaciens strains studied up to now transfer an active 6b gene plant cells. However, the role of this in natural tumour induction is unknown. Various effects on cell growth have been described, but precise mechanism by which causes these has not elucidated. Earlier experiments indicated that might increase auxin sensitivity as do A. rhizogenes rol genes. The from Tm4 (T-6b) was therefore compared with rolB and rolABC Although T-6b unable induce root formation, it strongly interfered elongation. In rolABC/T-6b coinfection carrots, T-6b-transformed cells stimulated outgrowth rolABC-transformed cells, indicating biologically product diffusible. Carrot roots containing T6b rapidly developed into unorganized calli. Nicotiana rustica continued their development, became very large. Fragments such formed callus at α-naphthaleneacetic acid concentrations inhibited normal fragments, suggesting genes may be reduce inhibitory high levels keep undifferentiated state.