Transcriptional changes related to secondary wall formation in xylem of transgenic lines of tobacco altered for lignin or xylan content which show improved saccharification

► Description of a xylogenic EST. ► Cell wall consequences of down-regulation of lignin and xylan. ► Improved saccharification of secondary walls but not primary walls. ► Transcriptional analysis of cell wall biosynthesis genes in modified transgenic lines. ► Identification of transcription factors.