GTP cyclohydrolase

GTP cy·clo·hy·dro·lase

an enzyme that catalyzes the reaction of GTP and H2O forming formate and a precursor of tetrahydrobiopterin; a deficiency of this enzyme will result in one form of malignant hyperphenylalaninemia.
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Sauna therapy can act via two distinct mechanisms to raise the levels of BH4, acting in both cases by raising the levels of the enzyme GTP cyclohydrolase I (GPCH), the first and rate-limiting enzyme in the de novo synthesis pathway for BH4.
GTP cyclohydrolase I (GPCH), in lymphocytes isolated from blood, was assayed by the method of Werner et al.
3] Human genes: CYP2C19, cytochrome P450, family 2, subfamily C, polypepetide 19; GCH1, GTP cyclohydrolase 1; TH, tyrosine hydroxylase; SPR, sepiapterin reductase (7,8-dihydrobiopterin:NADP+ oxidoreductase); PML, promyelocytic leukemia; RARA, retinoic acid receptor, alpha.
The first step of the plant pterin branch is catalyzed by an unusual GTP cyclohydrolase I (GTPCHI, Fig.
The Punch locus of Drosophila encodes GTP cyclohydrolase I, a multimeric enzyme that catalyzes the first step in pterin biosynthesis.
These diseases include: GTP Cyclohydrolase I Deficiency (dopa responsive dystonia) and Tyrosine Hydroxylase Deficiency (both currently treatable), Aromatic L Amino Acid Decarboxylase Deficiency, and Succinic Semialdehyde Dehydrogenase (SSADH) Deficiency.
sauna therapy Acts to increase BH4 Trials availabiity; mechanism published on via increased synthesis MCS, FM and of GTP cyclohydrolase I.
An exception is found in dominantly inherited GTP cyclohydrolase deficiency (doparesponsive dystonia) (15); in this disorder, it appears that the major impact is on the dopaminergic system, as an isolated decrease in HVA is observed (16).
4% of alleles in the study population) of the GTP cyclohydrolase gene (dopa-responsive dystonia, GCH1) and lower degrees of persistent pain after back surgery.