| 摘要 |
Provided are insolated DNA vectors which may be based on Agrobacterium binary vectors and which comprise: (a) a transfer nucleotide sequence comprising (i) a plant active promoter, operably linked to (ii) a recombinant tobacco rattle virus (TRV) nucleic acid which may corresponds to all or part of TRV RNA 1 and which includes: a sequence encoding a TRV trans acting factor, and cis acting elements, which confer on the TRV nucleic acid transcript the ability to replicate in the cytoplasm of a plant cell; and a heterologous nucleotide sequence which is foreign to said virus (which may be a cloning site, or a targeting sequence which is capable of down-regulating expression of a target gene); (b) border sequences which permit the transfer of the transfer nucleotide sequence into a plant cell genome. Preferred vectors include pBTADeltaAMPDelta16K (SEQ ID NO: 3) or pBTADeltaMP (SEQ ID NO: 2). Also provided are related materials and methods of use of such vectors e.g. to produce a cytoplasmically-replicating RNA which can be used to silence target genes in plants. |
