Mouse anti-Human sapiens (Human) GCH1 Monoclonal Antibody

Function

Positively regulates nitric oxide synthesis in umbilical vein endothelial cells (HUVECs). May be involved in dopamine synthesis. May modify pain sensitivity and persistence. Isoform GCH-1 is the functional enzyme, the potential function of the enzymatically inactive isoforms remains unknown

Subcellular Location

Cytoplasm; Nucleus

Disease Association

Hyperphenylalaninemia, BH4-deficient, B (HPABH4B) : A disease characterized by malignant hyperphenylalaninemia due to tetrahydrobiopterin deficiency, and defective neurotransmission due to depletion of the neurotransmitters dopamine and serotonin. The principal symptoms include: psychomotor retardation, tonicity disorders, convulsions, drowsiness, irritability, abnormal movements, hyperthermia, hypersalivation, and difficulty swallowing. Some patients may present a phenotype of intermediate severity between severe hyperphenylalaninemia and mild dystonia. In this intermediate phenotype, there is marked motor delay, but no intellectual disability and only minimal, if any, hyperphenylalaninemia. [The disease is caused by variants affecting the gene represented in this entry] | Dystonia, dopa-responsive (DRD) : A form of dystonia that responds to L-DOPA treatment without side effects. Dystonia is defined by the presence of sustained involuntary muscle contractions, often leading to abnormal postures. DRD typically presents in childhood with walking problems due to dystonia of the lower limbs and worsening of the dystonia towards the evening. It is characterized by postural and motor disturbances showing marked diurnal fluctuation. Torsion of the trunk is unusual. Symptoms are alleviated after sleep and aggravated by fatigue and exercise. [The disease is caused by variants affecting the gene represented in this entry]

Tissue Specificity

In epidermis, expressed predominantly in basal undifferentiated keratinocytes and in some but not all melanocytes (at protein level)

Subunit

Toroid-shaped homodecamer, composed of a dimer of pentamers. The inactive isoforms also form decamers and may possibly be incorporated into GCH1 heterodecamers, decreasing enzyme stability and activity. Interacts with AHSA1 and GCHFR/GFRP

Pathway

Cofactor biosynthesis; 7,8-dihydroneopterin triphosphate biosynthesis; 7,8-dihydroneopterin triphosphate from GTP: step 1/1

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