A novel promoter useful for altering the color of flowers of a plant, which is selected from the group consisting of: (1) a nucleic acid which comprises the nucleotide sequence represented by SEQ ID NO: 20, SEQ ID NO: 12 or SEQ ID NO: 21 and (2) a nucleic acid which maintains the same promoter activity as that of the nucleotide sequence represented by SEQ ID NO: 20, SEQ ID NO: 12 or SEQ ID NO: 21, and which comprises a nucleotide sequence that is produced by modifying the original nucleotide sequence by the addition, deletion and/or substitution of one or several nucleotide sequences, or can hybridize with a nucleotide acid comprising a nucleotide sequence complementary to the original nucleotide sequence under highly stringent conditions, or has a 90% or more sequence identity to the original nucleotide sequence.
