High impact information on TAT3

• Accumulation of the TAT protein and a 5- to 7-fold increase in its enzymatic activity was observed 7 to 9 h after application of octadecanoids, coronatine, or wounding [1].
• Coronatine-inducible tyrosine aminotransferase (TAT), which catalyses the transamination from tyrosine to p-hydroxyphenylpyruvate, is the first enzyme of a pathway leading via homogentisic acid to plastoquinone and tocopherols, the latter of which are known to be radical scavengers in plants [2].
• We conclude that jasmonate plays an important role in the signal transduction pathway regulating TAT activity and the biosynthesis of its product tocopherol [2].
• In order to elucidate the role of octadecanoids in the process of TAT induction in Arabidopsis thaliana (L.) Heynh., the jasmonate-deficient mutant delayed dehiscence (dde1) was used, in which the gene for 12-oxophytodienoic acid reductase 3 is disrupted [2].
• TAT can be also induced by the octadecanoids methyl jasmonate (MeJA) and methyl-12-oxophytodienoic acid (MeOPDA), as well as by wounding, high light, UV light and the herbicide oxyfluorfen [2].

Biological context of TAT3

• From these studies, evidence has also accumulated indicating that, in contrast to the remaining protein transport pathways present in the thylakoid membrane, the DeltapH/TAT pathway is able to mediate the transport of folded proteins [3].

Anatomical context of TAT3

• The intracellular and intraorganellar distribution of EGFP in the resulting transformants showed that while all the chloroplast transit peptides efficiently mediated the transport of EGFP into plastids, only those specific for the DeltapH/TAT pathway were able to direct the protein into the thylakoid lumen as well [3].

References