Phenylalanine amonia-lyase (PAL) is one of the most important enzymes that plays a key role in regulationof phenylpropanoid production in plants. It catalyzes the first step of the phenylpropanoid pathway in whichL-phenylalanine is deaminated to trans-cinnamic acid. This step is significant for metabolic engineering andhyper-expression of the major phenylpropanoid, methyl chav...

Flavonols, phenylalanine-derived secondary metabolites, have protective and regulatory functions in plants. In Arabidopsis thaliana, they are consecutively glycosylated at their 3-OH and 7-OH groups. UGT78D1 and UGT78D2 are the major flavonol 3-O-glycosyltransferases in Arabidopsis leaves. The ugt78d1 ugt78d2 double mutant, which was strongly compromised in the initial 3-O-glycosylation, showed...

The psoralen compounds, xanthotoxin and 4,5', 8-trimethylpsoralen, when activated, increased phenylalanine ammonia lyase (PAL) activity and the synthesis of pisatin in excised pea pods. Pods presoaked 1 hr with 4,5',8-trimethylpsoralen and then irradiated 4 minutes with 366 nanometer ultraviolet light had twice as much PAL activity 3 hours after irradiation and 12 times as much PAL activity 20 ...

Excising plant tissues has been found to increase the activity of phenylalanine ammonia-lyase (EC 4.1.3.5) (1, 4, 11, 12). This increase is probably due to de novo synthesis of this enzyme, since inhibitors of protein synthesis block the rise of PAL' activity (4, 11, 12). We suggested earlier (4) that the increase of PAL in gherkin hypocotyl segments was due to the release into the medium of re...

There are evidences showing that adverse impacts of aluminum (Al) on plants growth and development are associated with its effect on plasma membrane and cell wall. Influence of Al on peroxidation of membrane lipids, wall-bound phenolics, lignin, soluble phenolics and the activity of certain enzymes involved in metabolism of phenols, i.e., phenylalanine ammonia lyase (PAL) and polyphenol oxidase...

A tobacco (Nicotiana tabacum L. cv Samsun NN) cDNA clone coding the enzyme phenylalanine ammonia-lyase (PAL) was isolated from a cDNA library made from polyadenylated RNA purified from tobacco mosaic virus (TMV)-infected leaves. Southern analysis indicated that, in tobacco, PAL is encoded by a small family of two to four unclustered genes. Northern analysis showed that PAL genes are weakly expr...