The present invention provides a Populus 4-coumarate Co-enzyme A ligase gene promoter that directs expression in the xylem of plants. The promoter is used in methods designed to alter lignin content, lignin structure, cellulose content and combinations thereof. The methods comprise operably linking said promoter to heterologous nucleic acid molecules.https://digitalcommons.mtu.edu/patents/1051/thumbnail.jp
