Cambium/xylem-preferred promoters and uses thereof
The present invention relates to nucleic acid molecules corresponding to regulatory portions of genes whose expression is predominant in cambium and/or xylem. The invention also relates to compositions and methods of using the same to regulate the expression, in a cambium/xylem-preferred manner, of genes and/or any kind of nucleotide sequences in a plant. Nucleic acid molecules and its compositions include novel nucleotide sequences for cambium/xylem-preferred promoters identified and isolated from poplar ( Populus spp). Methods for expressing genes and/or any kind of nucleotide sequences in a plant using the promoter sequences disclosed herein are provided. The methods comprise stably incorporating into the genome of a plant cell a nucleotide sequence operably linked to a cambium/xylem-preferred promoter of the present invention and regenerating a stably transformed plant that expresses the nucleotide sequence.
1. An expression vector comprising: (i) an isolated nucleic acid molecule comprising a nucleotide sequence that is capable of initiating transcription of a gene in a plant cell, wherein said isolated nucleic acid molecule consists of the nucleotide sequence set forth in SEQ ID NO: 2 and (ii) a nucleic acid molecule which encodes a protein of interest, wherein (i) and (ii) are in operable linkage, wherein (i) is heterologous to (ii).
2. The expression vector of claim 1 , wherein said expression vector is a plasmid.
3. A recombinant plant cell, wherein said recombinant plant cell is transformed or transfected with an isolated nucleic acid molecule consisting of the nucleotide sequence set forth in SEQ ID NO: 2; and functions as a cambium/xylem-preferred promoter for a Populus gene encoding alpha-tubulin expression.
4. A recombinant plant cell, wherein said recombinant plant cell is transformed or transfected with the expression vector of claim 1 .
5. The recombinant plant cell of claim 3 , wherein said isolated nucleic acid molecule is stably incorporated in said recombinant plant cell's genome.
6. The recombinant plant cell of claim 4 , wherein said expression vector is stably incorporated in said recombinant plant cell's genome.
7. A method of making a recombinant host cell, said method comprising transforming or transfecting a cell with the expression vector of claim 1 .
8. A method of making a protein encoded by the expression vector of claim 1 , comprising transforming or transfecting a cell with said expression vector, and culturing said cell under conditions favorable for the expression of said protein.
9. The method of claim 7 , wherein said recombinant host cell is a plant cell.
10. A method for making a protein, said method comprising culturing a plant or plant part which comprises a recombinant host cell transformed or transfected with the expression vector of claim 1 , under conditions favoring production of said protein by said plant or plant part.
11. The method of claim 10 , wherein said plant is a dicot.
12. The method of claim 11 , wherein said dicot is Eucalyptus.
13. The method of claim 11 , wherein said dicot is Populus.
14. The method of claim 10 , wherein said plant is a monocot.
15. The method of claim 10 , wherein said plant is a gymnosperm.
16. The method of claim 15 , wherein said gymnosperm is Pinus.
17. A plant or plant part comprising the recombinant plant cell of claim 3 .
18. The plant of claim 17 , wherein said plant is a dicot.
19. The plant of claim 18 , wherein said dicot is Eucalyptus.
20. The plant of claim 18 , wherein said dicot is Populus.
21. The plant of claim 17 , wherein said plant is a monocot.
22. The plant of claim 17 , wherein said plant is a gymnosperm.
23. The plant of claim 22 , wherein said gymnosperm is Pinus.
24. The plant part of claim 17 , wherein said plant part is a seed.
25. The recombinant plant cell of claim 3 , wherein said recombinant plant cell is a pollen cell.
26. The method of claim 10 , wherein said plant part is selected from the group consisting of a root, a stem, a leaf, a flower, a fruit, a seed, a pistil, a stigma, a style, an ovary, an ovule, an stamen, an anther, and an filament.