| GO | Name |
| GO:0004033 | aldo-keto reductase (NADP) activity |
| GO:0004757 | sepiapterin reductase activity |
| GO:0005654 | nucleoplasm |
| GO:0005829 | cytosol |
| GO:0006729 | tetrahydrobiopterin biosynthetic process |
| GO:0006809 | nitric oxide biosynthetic process |
| GO:0046146 | tetrahydrobiopterin metabolic process |
| GO:0050661 | NADP binding |
| GO:0050999 | regulation of nitric-oxide synthase activity |
| GO:0070062 | extracellular exosome |