Disease relevance of Trh

• In this work, we show that enzymatic analyses of the putative DTRH enzyme expressed in Escherichia coli confirm that it acts as a tryptophan hydroxylase but can also hydroxylate phenylalanine, in vitro [1].

High impact information on Trh

• A single locus encodes both phenylalanine hydroxylase and tryptophan hydroxylase activities in Drosophila [2].
• Furthermore, ectopic expression of both Trh and Dfr (but not each one alone) triggered trh autoregulation in several embryonic tissues [3].
• Annotation of the sequenced Drosophila genome suggested the presence of an additional enzyme with extensive homology to mammalian tryptophan hydroxylase, which we have termed DTRH [1].
• Building upon the knowledge gained from the work in mice and zebrafish, it is possible to hypothesize that DTRH may be primarily neuronal in function and expression, and DTPH, which has been previously shown to have phenylalanine hydroxylation as its primary role, may be the peripheral tryptophan hydroxylase in Drosophila [1].

References