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Match the items in Group 1 with their functions in Group 2:
Group 1
P. rol genes
Q. Opines
R. Virulence genes
S. Aux and cyt genes
Group 2
1. Food and energy source
2. Tumor formation
3. Hairy root induction
4. T-DNA transfer and integration
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- P-4, Q-3, R -2, S-1
- P-3, Q-2, R-4, S-1
- P-1, Q-3, R-4, S-2
- P-3, Q-1, R-4, S-2
Correct Option: D
P>3 : The rolA, rolB and rolC genes are plant oncogenes that are carried in plasmids of the plant pathogen Agrobacterium rhizogenes. Following agrobacterial infection, these genes are transferred into the plant genome and cause tumor formation and hairy root disease.
Q>1 : Agrobacterium rhizogenes causes hairy root disease in plants. The transformed roots start producing opines which serve as carbon or nitrogen source for the infecting bacteria.
R>4 : Genes in the virulence region are grouped into the operons virABCDEFG, which code for the enzymes responsible for mediating transduction of T-DNA to plant cells.
S>2 : Agrobacterium rhizogenes transfers a piece of oncogenic DNA, i.e. T-DNA. The T-DNA contains onc genes, the expression of which is responsible for the tumorous character of the transformed plant cells. Three onc genes are of prime importance: cyt, aux1, aux2.
