Send to

Choose Destination
EMBO J. 1989 Jul;8(7):1899-906.

Tissue- and cell-specific activity of a phenylalanine ammonia-lyase promoter in transgenic plants.

Author information

Institute of Plant Science Research, Cambridge Laboratory, UK.


Phenylalanine ammonia-lyase (PAL) catalyses the first step in the biosynthesis of phenylpropanoids, which form a wide variety of plant secondary products. The transcription of PAL is regulated in response to various factors that induce the accumulation of flavonoids, lignin and compounds thought to be involved in plant defence reactions. The 5' upstream sequence of a PAL gene from Phaseolus vulgaris was fused to the coding region of the reporter gene encoding beta-glucuronidase (GUS), and transformed into potato and tobacco plants. Histochemical analysis of GUS expression showed that the PAL promoter was active in specific cell types that accumulated phenylpropanoid derivatives in response to mechanical wounding, and also during normal development of the xylem and flower. In xylem that had undergone secondary thickening, GUS activity occurred in rays of cells thought to be the xylem parenchyma. It was postulated that PAL activity in these cells could provide intermediates for lignin synthesis in xylem vessels that had terminally differentiated.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center