Compositions and methods are provided for modifying a trait of a plant. Isolated polynucleotide and polypeptide sequences are provided, along with an expression vector comprising the isolated polynucleotide, a host cell comprising the isolated polynucleotide, and a transgenic plant comprising the isolated polynucleotide. Also provided is a method for producing a transgenic plant, a method for screening for a compound that may modify the trait and a method for identifying other homologous polynucleotide and polypeptide sequences.