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EgMYB2, a member of a new subgroup of the R2R3 MYB family of transcription factors, was cloned from a library consisting of RNA from differentiating Eucalyptus xylem. EgMYB2 maps to a unique locus on the Eucalyptus grandis linkage map and co‐localizes with a quantitative trait locus (QTL) for lignin content. Recombinant EgMYB2 protein was able to bind specifically the cis‐regulatory regions of the promoters of two lignin biosynthetic genes, cinnamoyl‐coenzyme A reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD), which contain MYB consensus binding sites. EgMYB2 was also able to regulate their transcription in both transient and stable expression assays. Transgenic tobacco plants over‐expressing EgMYB2 displayed phenotypic changes relative to wild‐type plants, among which were a dramatic increase in secondary cell wall thickness, and an alteration of the lignin profiles. Transcript …