Development of the pteridine pathway in the zebrafish, Danio rerio

Citation
I. Ziegler et al., Development of the pteridine pathway in the zebrafish, Danio rerio, J BIOL CHEM, 275(25), 2000, pp. 18926-18932
Citations number
63
Categorie Soggetti
Biochemistry & Biophysics
Journal title
JOURNAL OF BIOLOGICAL CHEMISTRY
ISSN journal
00219258 → ACNP
Volume
275
Issue
25
Year of publication
2000
Pages
18926 - 18932
Database
ISI
SICI code
0021-9258(20000623)275:25<18926:DOTPPI>2.0.ZU;2-T
Abstract
In the zebrafish, the peripheral neurons and the pigment cells are derived from the neural crest and share the pteridine pathway, which leads either t o the cofactor tetrahydrobiopterin or to xanthophore pigments. The componen ts of the pteridine pattern were identified as tetrahydrobiopterin, sepiapt erin, 7-oxobiopterin, isoxanthopterin, and 2,4,7-trioxopteridine. The expre ssion of GTP cyclohydrolase I activity during the first 24-h postfertilizat ion, followed by 6-pyruvoyl-5,6,7,8-tetrahydropterin synthase and sepiapter in reductase, suggest an early supply of tetrahydrobiopterin for neurotrans mitter synthesis in the neurons and for tyrosine supply in the melanophores . At 48-h postfertilization, sepiapterin formation branches off the de novo pathway of tetrahydrobiopterin synthesis, Sepiapterin, via 7,8-dihydrobiop terin and biopterin, serves as a precursor for the formation of 7-oxobiopte rin, which may be further catabolized to isoxanthopterin and 2,4,7-trioxopt eridine, Neither 7,8-dihydrobiopterin nor biopterin is a substrate for xant hine oxidoreductase. In contrast, both of these compounds are oxidized at C -7 by a xanthine oxidase variant form, which is inactivated by KCN, but is insensitive to allopurinol. The oxidase and the dehydrogenase form of xanth ine oxidoreductase as well as the xanthine oxidase variant have specific de velopmental patterns. It follows that GTP cyclohydrolase I, the formation o f sepiapterin, and the xanthine oxidoreductase family control the pteridine pathway in the zebrafish.