Hypersensitive aba receptors

Abstract

Hypersensitive PYR/PYL polypeptides, compositions, and methods are provided.

What is claimed is: 
     
         1 . An isolated nucleic acid comprising a polynucleotide encoding a mutated PYR/PYL receptor polypeptide comprising an amino acid substitution corresponding to the amino acid F61, V81, I110, E141, and A160 in PYR1 as set forth in SEQ ID NO:1, wherein the mutated PYR/PYL receptor has increased sensitivity to abscisic acid compared to a control PYR/PYL receptor lacking the substitution. 
     
     
         2 . The isolated nucleic acid of  claim 1 , wherein the PYR/PYL receptor polypeptide comprises an amino acid substitution corresponding to the amino acid F61. 
     
     
         3 . The isolated nucleic acid of  claim 2 , wherein the amino acid substitution is selected from L and M. 
     
     
         4 . The isolated nucleic acid of  claim 1 , wherein the PYR/PYL receptor polypeptide comprises an amino acid substitution corresponding to the amino acid V81. 
     
     
         5 . The isolated nucleic acid of  claim 4 , wherein the amino acid substitution is selected from I and Y. 
     
     
         6 . The isolated nucleic acid of  claim 1 , wherein the PYR/PYL receptor polypeptide comprises an amino acid substitution corresponding to the amino acid I110. 
     
     
         7 . The isolated nucleic acid of  claim 6 , wherein the amino acid substitution is selected from C and S. 
     
     
         8 . The isolated nucleic acid of  claim 1 , wherein the PYR/PYL receptor polypeptide comprises an amino acid substitution corresponding to the amino acid E141. 
     
     
         9 . The isolated nucleic acid of  claim 8 , wherein the amino acid substitution is selected from C, I, L, M, N, T, V, W, and Y. 
     
     
         10 . The isolated nucleic acid of  claim 1 , wherein the PYR/PYL receptor polypeptide comprises an amino acid substitution corresponding to the amino acid A160. 
     
     
         11 . The isolated nucleic acid of  claim 8 , wherein the amino acid substitution is selected from C, I, and V. 
     
     
         12 . The isolated nucleic acid of  claim 1 , wherein the mutated PYR/PYL receptor polypeptide is substantially identical to any of SEQ ID NOs:1-119 or SEQ ID NOs:155-361 or comprises any of SEQ ID NOs: 120-123. 
     
     
         13 . The isolated nucleic acid of  claim 1 , wherein the polynucleotide encodes a fusion protein, the fusion protein comprising the mutated PYR/PYL receptor polypeptide and a fusion partner protein. 
     
     
         14 . The isolated nucleic acid of  claim 13 , wherein the fusion partner protein is a transcriptional activation or modulation domain. 
     
     
         15 . The isolated nucleic acid of  claim 14 , wherein the transcriptional activator is VP16 or VP64. 
     
     
         16 . The isolated nucleic acid of  claim 13 , wherein the fusion protein further comprises a nuclear localization signal sequence. 
     
     
         17 . A cell comprising a heterologous polynucleotide of  claim 1 . 
     
     
         18 . The cell of  claim 17 , wherein the cell is a non-plant eukaryotic cell. 
     
     
         19 . A plant comprising the polynucleotide of  claim 1 . 
     
     
         20 . A plant comprising an in situ mutated PYR/PYL receptor polypeptide comprising an amino acid substitution corresponding to the amino acid F61, V81, I110, E141, and A160 in PYR1 as set forth in SEQ ID NO:1, wherein the mutated PYR/PYL receptor polypeptide has increased sensitivity to abscisic acid compared to a control PYR/PYL receptor lacking the substitution. 
     
     
         21 . An expression cassette comprising a promoter operably linked to the polynucleotide of  claim 1 , wherein introduction of the expression cassette into a plant results in the plant having increased sensitivity to abscisic acid compared to a control plant lacking the expression cassette. 
     
     
         22 . The expression cassette of  claim 21 , wherein the promoter is heterologous to the polynucleotide. 
     
     
         23 . The expression cassette of  claim 21 , wherein the promoter is inducible. 
     
     
         24 . The expression cassette of  claim 21 , wherein the promoter is a stress-inducible promoter. 
     
     
         25 . An expression vector comprising the expression cassette of  claim 21 . 
     
     
         26 . A plant comprising the expression cassette of  claim 21 , wherein the plant has increased sensitivity to abscisic acid compared to a control plant lacking the expression cassette. 
     
     
         27 . A plant cell from the plant of  claim 19 . 
     
     
         28 . A seed, flower, leaf, fruit, processed food, or food ingredient from the plant of  claim 19 . 
     
     
         29 . A method of producing a plant having increased sensitivity to abscisic acid, the method comprising:
 introducing the expression cassette of  claim 21  into a plurality of plants; and   selecting a plant that expresses the polynucleotide from the plurality of plants.   
     
     
         30 . A method of producing a plant having increased sensitivity to abscisic acid, the method comprising:
 introducing a mutation into a polynucleotide encoding a PYR/PYL polypeptide, wherein the mutation results in the polynucleotide of  claim 1 .   
     
     
         31 . The method of  claim 30 , wherein the introducing occurs in situ in the genome of a plant cell. 
     
     
         32 . The method of  claim 31 , wherein the introducing comprises clustered regularly interspaced short palindromic repeats (CRISPR)/Cas genome editing. 
     
     
         33 . A guide ribonucleic acid (gRNA) comprising:
 a) a CRISPR ribonucleic acid (crRNA) that is substantially identical to SEQ ID NOS: 363, 364, 365, 366, 367 or 369; and   b) a transacting ribonucleic acid (tracRNA),   wherein the PYR/PYL mutation target site comprises a nucleic acid that encodes for V89 of PYL-E or E149 of PYL-E.