Reducing levels of nicotinic alkaloids in plants

1. A method for reducing a nicotinic alkaloid in a plant comprising down-regulating A622 and NBB1 expression relative to a non-transformed control plant, wherein A622 is encoded by a nucleotide sequence selected from the group consisting of:

(a) the nucleotide sequence set forth in SEQ ID NO: 1;

(b) a nucleotide sequence that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 2; and

(c) a nucleotide sequence that encodes a polypeptide with one or more conservative amino acid substitutions as compared to the polypeptide having the amino acid sequence set forth in SEQ ID NO: 2 and encoding a polypeptide with A622 expression;

and wherein NBB1 is encoded by a nucleotide sequence selected from the group consisting of:

(i) the nucleotide sequence set forth in SEQ ID NO: 3;

(ii) a nucleotide sequence that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 4; and

(iii) a nucleotide sequence that encodes a polypeptide with one or more conservative amino acid substitutions as compared to the polypeptide having the amino acid sequence set forth in SEQ NO: 4 and encoding a polypeptide with NBB1 expression.

2. The method of claim 1 , wherein the nicotinic alkaloid is nicotine.

3. The method of claim 1 , wherein the nicotinic alkaloid is anatabine.

4. A genetically engineered plant having reduced A622 and NBB1 expression relative to a non-transformed control plant, wherein A622 is encoded by a nucleotide sequence selected from the group consisting of:

(a) the nucleotide sequence set forth in SEQ ID NO: 1;

(b) a nucleotide sequence that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 2; and

(c) a nucleotide sequence that encodes a polypeptide with one or more conservative amino acid substitutions as compared to the polypeptide having the amino acid sequence set forth in SEQ ID NO: 2 and encoding a polypeptide with A622 expression;

and wherein NBB1 is encoded by a nucleotide sequence selected from the group consisting of:

(i) the nucleotide sequence set forth in SEQ ID NO: 3;

(ii) a nucleotide sequence that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 4; and

(iii) a nucleotide sequence that encodes a polypeptide with one or more conservative amino acid substitutions as compared to the polypeptide having the amino acid sequence set forth in SEQ ID NO: 4 and encoding a polypeptide with NBB1 expression.

5. The plant of claim 4 , wherein the plant is a tobacco plant.

6. The tobacco plant of claim 5 , wherein the tobacco plant has reduced nicotinic alkaloid content relative to a non-transformed control plant.

7. The method of claim 6 , wherein the nicotinic alkaloid is nicotine.

8. The method of claim 6 , wherein the nicotinic alkaloid is anatabine.

9. A reduced-nicotine tobacco product comprising the tobacco plant of claim 6 .

10. The reduced-nicotine tobacco product of claim 9 , wherein the tobacco product is selected from the group consisting of a cigarette, cigarette tobacco, a cigar, cigar tobacco, pipe tobacco, chewing tobacco, snuff, leaf tobacco, shredded tobacco, and cut tobacco.

11. A tobacco plant produced by a method comprising:

(a) mutagenizing a plurality of tobacco plant cells thereby producing a plurality of mutagenized cells;

screening plants generated from the mutagenized cells, or progeny produced therefrom, for reduced expression of A622 and NBB1; and

(c) selecting one or more of the plants or progeny comprising a mutation in the nucleotide sequence set forth in SEQ ID NO: 1 and SEQ ID NO: 3, wherein the plant or progeny has reduced nicotine content as compared to a control tobacco plant.

12. A tobacco product comprising the tobacco plant of claim 11 , having a reduced expression of A622 and NBB1 relative to a control tobacco plant, wherein the tobacco product is selected from the group consisting of smoking cessation products, cigarettes, cigarette tobacco, cigars, cigar tobacco, snus, pipe tobacco, and chewing tobacco.

13. A product comprising the tobacco plant of claim 11 , having a reduced expression of A622 and NBB1 relative to a control tobacco plant, wherein the product is selected from the group consisting of a food product, food ingredient, feed product, feed ingredient, nutritional supplement, and biofuel.

14. A tobacco plant comprising plant cells into which one or more mutations are introduced into:

(a) the region of SEQ ID NO: 1 that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 2; and

(b) the region of SEQ ID NO: 3 that encodes a polypeptide having the amino acid sequence set forth in SEQ ID NO: 4;

wherein the plant exhibits reduced expression of a gene product encoded by SEQ ID NO: 1 and SEQ ID NO: 3 as compared to a control tobacco plant.

15. The tobacco plant of claim 14 , wherein the tobacco plant exhibits a reduced nicotine level as compared to a control plant.

16. Seeds from the tobacco plant of claim 14 , or progeny plant thereof, wherein the seeds comprise in their genomes the one or more mutations.

17. A product comprising the tobacco plant of claim 15 , having reduced expression of a gene product encoded by SEQ ID NO: 1 and SEQ ID NO: 3 as compared to a control tobacco plant, and having a reduced level of nicotine as compared to a product produced from a control tobacco plant, wherein the product is selected from the group consisting of a tobacco product, food product, food ingredient, feed product, feed ingredient, nutritional supplement, and biofuel.

18. The tobacco product of claim 17 , wherein the product is selected from the group consisting of smoking cessation products, cigarettes, cigarette tobacco, cigars, cigar tobacco, snus, pipe tobacco, and chewing tobacco.