Maize Stress-Responsive NAC Transcription Factors and Promoter and Methods of Use

Abstract

Methods and compositions for modulating plant development are provided. Polynucleotide sequences encoding ZmSNAC polypeptides are provided, as are the amino acid sequences of the encoded polypeptides. The sequences can be used in a variety of methods including modulating root development, modulating floral development, modulating leaf and/or shoot development, modulating senescence, modulating seed size and/or weight, and modulating tolerance of plants to abiotic stress. Transformed plants, plant cells, tissues, and seed are also provided. A stress-inducible ZmSNAC1 promoter is also provided.

1 . An isolated polypeptide having transcription factor activity and comprising an amino acid sequence at least 95% identical to SEQ ID NO: 2, 4, 6, 8 or 10. 
     
     
         2 . An isolated polynucleotide comprising a nucleotide sequence at least 95% identical to SEQ ID NO: 1, 3, 5, 7 or 9, or the complement thereof. 
     
     
         3 . A transgenic plant comprising a polynucleotide of  claim 2  operably linked to a promoter that drives expression in the plant, wherein transcription factor activity in said plant is modulated relative to a control plant. 
     
     
         4 . The plant of  claim 3 , wherein said transcription factor activity is increased. 
     
     
         5 . The plant of  claim 3 , wherein said promoter is a tissue-preferred promoter, a constitutive promoter, or an inducible promoter. 
     
     
         6 . The plant of  claim 3  wherein said tissue-preferred promoter is a root-preferred promoter, a leaf-preferred promoter, a shoot-preferred promoter or an inflorescence-preferred promoter. 
     
     
         7 . The plant of  claim 3 , wherein said modulation of transcription factor activity affects floral development. 
     
     
         8 . The plant of  claim 3 , wherein said modulation of transcription factor activity affects root development. 
     
     
         9 . The plant of  claim 3 , wherein the stress tolerance of said plant is increased relative to a control. 
     
     
         10 . The plant of  claim 9 , wherein the drought tolerance of said plant is increased relative to a control. 
     
     
         11 . The plant of  claim 3 , wherein said promoter is stress-induced. 
     
     
         12 . A transformed seed of the plant of  claim 3 . 
     
     
         13 . The plant of  claim 3 , wherein said plant is maize, wheat, rice, barley, sorghum, rye, soybean, brassica or sunflower. 
     
     
         14 . A plant in which expression of a native genomic locus is modified, said genomic locus comprising a polynucleotide of  claim 2 . 
     
     
         15 . A method of modulating transcription factor activity in a plant, comprising transforming said plant with a polynucleotide of  claim 2  operably linked to a promoter. 
     
     
         16 . The method of  claim 15  wherein said modulation of transcription factor activity improves stress tolerance. 
     
     
         17 . The method of  claim 15  wherein said promoter is a tissue-preferred or inducible promoter, or is both tissue-preferred and inducible. 
     
     
         18 . The method of  claim 17 , wherein said promoter is stress-inducible. 
     
     
         19 . The method of  claim 17 , wherein senescence is delayed. 
     
     
         20 . An isolated nucleic acid molecule comprising a first polynucleotide which initiates transcription of a second, operably-linked polynucleotide in a plant cell, wherein the first polynucleotide is selected from the group consisting of:
 a) SEQ ID NO: 11;   b) at least 500 contiguous nucleotides of SEQ ID NO: 11.   
     
     
         21 . An expression cassette comprising the first and second polynucleotides of  claim 20 . 
     
     
         22 . A plant cell having stably incorporated into its genome the expression cassette of  claim 21 . 
     
     
         23 . A plant having stably incorporated into its genome the expression cassette of  claim 21 .