Transformation of Nicotiana paniculata L., a recalcitrant species, using a T-DNA construct carrying two WUSCHEL-related homeobox genes.

A binary vector carrying two WUSCHEL-related homeobox (WOX) genes, WOX2 and WOX8, under the control of a chemical-inducible expression system, worked in the transformation in N. paniculata, a recalcitrant species of Nicotiana. The resulting transformants exhibited improved culture performance in regeneration from leaf segments and suspended cells. Multicellular masses generated from freely suspended cells showed a specific cell division pattern similar to that of somatic embryo, likely owing to the function of the two WOX genes.