Human Sepiapterin Reductase (SPR) ELISA Kit

Assay Genie's Sepiapterin Reductase (SPR) kit quantitatively measures human SPR protein in tissue homogenates and related sample types. SPR catalyzes the NADPH-dependent reduction of sepiapterin to 7,8-dihydrobiopterin in the final stage of tetrahydrobiopterin (BH4) biosynthesis. Because BH4 is an obligate cofactor for phenylalanine hydroxylase, tyrosine hydroxylase, tryptophan hydroxylase, and all three nitric oxide synthase isoforms, SPR levels directly influence monoamine neurotransmitter production and nitric oxide signaling.

The 96-assay format produces an absorbance-based signal captured on a standard microplate reader, providing throughput suitable for cohort studies and time-course experiments. Validated sample matrices include tissue homogenates, with protocols accommodating additional preparations such as cell lysates prepared by the end user. Common research applications include DOPA-responsive dystonia, Segawa syndrome, Parkinson disease, autism spectrum phenotypes linked to BH4 deficiency, and cellular pharmacology investigations of nitric oxide pathway regulation.

Reagents are supplied on cold packs and should be stored refrigerated upon arrival to preserve antibody and substrate activity until first use. The workflow uses pre-coated microplate wells, a calibration standard series, biotinylated detection reagent, streptavidin-HRP conjugate, wash buffer, and TMB substrate, with a stop solution provided for endpoint development. For research use only; not intended for diagnostic or clinical decision-making.