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T-DNA
The transfer DNA (abbreviated T-DNA) is the transferred DNA of the Ti plasmid, tumor-inducing (Ti) plasmid of some species of bacteria such as ''Agrobacterium tumefaciens'' and ''Agrobacterium rhizogenes (actually an Ri plasmid)''. The T-DNA is transferred from bacterium into the host plant's Cell nucleus, nuclear DNA genome. The capability of this specialized tumor-inducing (Ti) plasmid is attributed to two essential regions required for DNA transfer to the host cell. The T-DNA is bordered by 25-base-pair repeats on each end. Transfer is initiated at the right border and terminated at the left border and requires the ''vir'' genes of the Ti plasmid. The bacterial T-DNA is about 24,000 base pairs long and contains plant-expressed genes that code for enzymes synthesizing opines and phytohormones. By transferring the T-DNA into the plant genome, the bacterium essentially reprograms the plant cells to grow into a tumor and produce a unique food source for the bacteria. The synthesis o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transfer DNA Binary System
A transfer DNA (T-DNA) binary system is a pair of plasmids consisting of a T-DNA binary vector and a ''vir'' helper plasmid. The two plasmids are used together (thus ''binary'') to produce genetically modified plants. They are artificial Vector (molecular biology), vectors that have been derived from the naturally occurring Ti plasmid found in bacterial species of the genus ''Agrobacterium'', such as ''Agrobacterium tumefaciens, A. tumefaciens''. The binary vector is a ''shuttle vector'', so-called because it is able to DNA replication, replicate in multiple hosts (e.g. ''E. coli, Escherichia coli'' and ''Agrobacterium''). Systems in which Transfer DNA, T-DNA and ''vir'' genes are located on separate replicons are called T-DNA binary systems. T-DNA is located on the binary vector (the non-T-DNA region of this vector containing origin(s) of replication that could function both in ''E. coli'' and ''Agrobacterium'', and antimicrobial resistance, antibiotic resistance genes used to selec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
