Stem rust resistance gene
Compositions and methods for enhancing the resistance of plants, particularly wheat and triticale plants to stem rust caused by Puccinia graminis f. sp. tritici are provided. The compositions comprise nucleic acid molecules encoding resistance (R) gene products and variants thereof and plants, seeds, and plant cells comprising such nucleic acid molecules. The methods for enhancing the resistance of a plant to stem rust comprise introducing a nucleic acid molecule encoding an R gene product into a plant cell. Additionally provided are methods for using the resistant plants in agriculture to limit stem rust.
1 . A transgenic wheat plant or transgenic wheat seed comprising stably incorporated in its genome a heterologous polynucleotide construct comprising a nucleotide sequence selected from the group consisting of:
(a) the nucleotide sequence set forth in SEQ ID NO: 1, 2, or 4;
(b) a nucleotide sequence encoding the amino acid sequence set forth in SEQ ID NO: 3; and
(c) a nucleotide sequence encoding an amino acid sequence having at least 95% sequence identity to the amino acid sequence set forth in SEQ ID NO: 3, wherein the heterologous polynucleotide construct is capable of conferring resistance to stem rust to a wheat plant comprising the heterologous polynucleotide construct.
2 . The transgenic wheat plant or transgenic wheat seed of claim 1 , wherein the nucleic acid molecule of (c) encodes a protein comprising a coiled-coil domain, a nucleotide-binding domain, and a leucine-rich repeat domain.
3 . The transgenic wheat plant or transgenic wheat seed of claim 2 , wherein at least one of the coiled-coil domain, the nucleotide-binding domain, and the leucine-rich repeat domain comprises an amino acid sequence having at least 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the corresponding domain in SEQ ID NO: 3.
4 . The transgenic wheat plant or transgenic wheat seed of claim 1 , wherein the polynucleotide construct further comprises a promoter operably linked to the nucleotide sequence for the expression of the nucleotide sequence in a plant.
5 . The transgenic wheat plant or transgenic wheat seed of claim 4 , wherein the promoter is selected from the group consisting of pathogen-inducible, constitutive, tissue-preferred, wound-inducible, and chemical-regulated promoters.
6 . The transgenic wheat plant or transgenic wheat seed of claim 1 , wherein the transgenic wheat plant or transgenic wheat seed comprises enhanced resistance to wheat stem rust caused by at least one race of Puccinia graminis f. sp. tritici , relative to a control wheat plant.
7 . A method for enhancing the resistance of a wheat plant to wheat stem rust,
the method comprising introducing a heterologous polynucleotide construct into at least one wheat plant cell, the heterologous polynucleotide construct comprising a nucleotide sequence selected from the group consisting of:
(a) the nucleotide sequence set forth in SEQ ID NO: 1, 2, or 4;
(b) a nucleotide sequence encoding the amino acid sequence set forth in SEQ ID NO: 3; and
(c) a nucleotide sequence encoding an amino acid sequence having at least 95% sequence identity to the amino acid sequence set forth in SEQ ID NO: 3, wherein the heterologous polynucleotide construct is capable of conferring resistance to stem rust to a wheat plant comprising the heterologous polynucleotide construct.
8 . A method of limiting wheat stem rust in agricultural crop production, the method comprising planting a transgenic wheat seed and growing a wheat plant under conditions favorable for the growth and development of the wheat plant, wherein the transgenic wheat seed comprises stably incorporated in its genome a heterologous polynucleotide construct comprising a nucleotide sequence selected from the group consisting of:
(a) the nucleotide sequence set forth in SEQ ID NO: 1, 2, or 4;
(b) a nucletoide sequence encoding the amino acide sequence set forth in SEQ ID NO: 3; and
(c) a nucleotide sequence encoding an amino acid sequence having at least 95% sequence identity to the amino acid sequence set forth in SEQ ID NO: 3, wherein the heterologous polynucleotide construct is capable of conferring resistance to stem rust to a wheat plant comprising the heterologous polynucleotide construct.
9 . A transgenic wheat plant identified by detecting in the wheat plant the presence of the R gene, Sr27, wherein the transgenic wheat plant comprises a heterologous polynucleotide construct comprising the R gene, and wherein the R gene comprises a nucleotide sequence selected from the group consisting of:
(a) the nucleotide sequence set forth in SEQ ID NO: 1, 2, or 4;
(b) a nucleotide sequence encoding the amino acid sequence set forth in SEQ ID NO: 3; and
(c) a nucleotide sequence encoding an amino acid sequence having at least 95% sequence identity to the amino acid sequence set forth in SEQ ID NO: 3, wherein the R gene is capable of conferring resistance to stem rust to a wheat plant comprising the R gene;
or a transgenic seed of the transgenic wheat plant, wherein the transgenic seed comprises the heterologous polynucleotide construct.