A plant gene structure comparison and evolution database with 25 species. Annotated genes were extracted from the species and classified based on Pfam motif. Phylogenetic tree was reconstructed for each gene category integrated exon-intron and protein motif information. Both the sequences and gene structure information for each identified gene are freely available for online access on the PIECE website. The PIECE database provides a user-friendly graphical viewer that displays a gene structure pattern diagram linked to the resulting bootstrapped dendrogram for each gene family. Gene structure information can be displayed and retrieved in nucleotide sequence or in aligned protein sequence.