Method for decreasing the alkaloid content of a tobacco plant

A method of modulating (e.g. decreasing) the content of a tobacco specific nitrosamine (TSNA) or a precursor of a TSNA in a tobacco plant or part thereof, the method comprising modifying said plant or a cell or cell culture by modulating the activity or expression of at least one gene encoding a SOUL haem-binding protein.

Use of at least one gene encoding a SOUL haem-binding protein for modulating alkaloid content of a cell or plant or part thereof or a cell or cell culture.

A method for producing a plant or part thereof, a cell or cell culture, a plant propagation material, a leaf, a cut harvested leaf, a processed leaf or a cut and processed leaf which has modulated (e.g. decreased) alkaloid content, the method comprising modifying said plant or cell or cell culture to modulate the activity or expression of at least one gene encoding a SOUL haem-binding protein.

A method or use according to any one of the preceding claims, wherein the alkaloid content is modulated (e.g. decreased) in comparison to a plant or cell or cell culture which has not been modified to modulate the activity or expression of the at least one gene encoding a SOUL haem-binding protein.

A plant or part thereof or a cell or cell culture which has been modified to achieve a modulation (e.g. decrease) in alkaloid content in comparison to an unmodified plant or unmodified cell or cell culture, wherein the modification is the reduction of the activity or expression of at least one gene encoding a SOUL haem-binding protein.

Use of a nucleotide sequence of at least one gene encoding a SOUL haem-binding protein to select a plant having modulated (e.g. decreased) alkaloid content and/or modulated (e.g. decreased) content of tobacco specific nitrosamine (TSNA) or a precursor of a TSNA, preferably wherein the sequence of the SOUL haem-binding protein is selected from SEQ ID No. 1, 4, 7, 10, 13, 16, 19 or 22 or a functional variant or functional fragment or orthologue thereof, or a sequence which has at least 80% identity to SEQ ID No. 1, 4, 7, 10, 13, 16, 19 or 22;

• or wherein the at least one gene encoding a SOUL haem-binding protein comprises a nucleotide sequence as set out in SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24 or a functional variant or functional fragment or orthologue thereof, or a sequence which has at least 80% identity to SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24.

A mutant of a plant carrying a heritable mutation in a nucleotide sequence of at least one gene encoding a SOUL haem-binding protein, preferably wherein the gene is selected from SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24 or a functional variant or functional fragment or orthologue thereof, or a sequence which has at least 80% identity to SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24;

• wherein said heritable mutation modulates (e.g. decreases) the activity or expression of the at least one gene encoding a SOUL haem-binding protein and wherein the mutant plant has modulated (e.g. decreased) alkaloid content and/or modulated content of a tobacco specific nitrosamine (TSNA) or a precursor of a TSNA relative to a comparable plant which does not carry said heritable mutation.

A harvested leaf, a processed leaf or cured tobacco material produced from a plant comprising a modification in a nucleotide sequence of at least one gene encoding a SOUL haem-binding protein, wherein the at least one gene is selected from SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24 or a functional variant or functional fragment or orthologue thereof, or a sequence which has at least 80% identity to SEQ ID No. 2, 3, 5, 6, 8, 9, 11, 12, 14, 15, 17, 18, 20, 21, 23 or 24;

• or a functional variant or functional fragment or orthologue thereof;
• wherein said modification modulates (e.g. decreases) the activity or expression of the at least one gene encoding a SOUL haem-binding protein and wherein said plant has modulated (e.g. decreased) alkaloid content and/or modulated content of a tobacco specific nitrosamine (TSNA) or a precursor of a TSNA relative to a comparable plant which does not carry said modification in the at least one gene encoding a SOUL haem-binding protein.

A method, a leaf, a plant, a plant propagation material, a harvested leaf, a processed tobacco, a tobacco product, a use or a combination thereof as described herein with reference to the description and drawings.