Developmentally regulated patterns of expression directed by poplar PAL promoters in transgenic tobacco and poplar.

摘要: Phenylalanine ammonia-lyase (PAL) catalyzes the first step in phenylpropanoid metabolism and plays a central role biosynthesis of compounds. We have previously cloned two PAL genes, PAL1 PAL2, from Populus trichocarpa × P. deltoides F1 hybrid. Here, we describe properties PAL2 promoters their expression patterns transgenic tobacco poplar. The were 75% identical regions sequenced, each contained copies AC-rich putative cis-acting elements that matched consensus plant myb transcription factor binding site sequence. In tobacco, PAL1-GUS PAL2-GUS fusions directed similar developing primary xylem leaves, stems, other organs, secondary stems. Contrary to documented PAL1/2 poplar, no either fusion was detected epidermal or subepidermal cell layers young leaves highest levels roots high GUS activity cells as well phloem fibers. low woody weak absent xylem. poplar are very those mRNA accumulation However, distinct by promoter show does not accurately reflect all aspects