Pteridines as nonretinal regulators of light-dependent melatonin biosynthesis.
AUTOR(ES)
Cremer-Bartels, G
RESUMO
6-Formylpterin was purified by paper chromatography, and bovine pineal hydroxyindole-O-methyltransferase (S-adenosyl-L-methionine:N-acetylserotonin O-methyl-transferase; EC 2.1.1.4) was purified by flat-bed gel electrofocusing. Fractions of the methyltransferase with isoelectric points at pH 5.0, 5.7, and 5.2 were tested in the presence of 6-formylpterin, and decreased activities were found. Because 6-formylpterin is one of the photolytic products of folic acid and decreased serum folic acid has been reported in light-exposed men, we suggest that pteridines may be involved in nonretinal effects of light on pineal melatonin biosynthesis. It may be that this metabolic pathway is an evolutionary relic of primitive light responses of pigmentation mechanism.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=349409Documentos Relacionados
- PORA and PORB, Two Light-Dependent Protochlorophyllide-Reducing Enzymes of Angiosperm Chlorophyll Biosynthesis.
- A prokaryotic origin for light-dependent chlorophyll biosynthesis of plants.
- Light-dependent Induction of Polyunsaturated Fatty Acid Biosynthesis in Greening Cucumber Cotyledons 1
- Light-Dependent Regulation of Cyanobacterial Phytochrome Expression
- Mechanism of light-dependent proton translocation by bacteriorhodopsin.