A single polypeptide catalyzing the conversion of phytoene to zeta-carotene is transcriptionally regulated during tomato fruit ripening.
AUTOR(ES)
Pecker, I
RESUMO
The cDNA of the gene pds from tomato, encoding the carotenoid biosynthesis enzyme phytoene desaturase, was cloned, and its nucleotide sequence was determined. Cells of Escherichia coli that expressed the tomato pds gene could convert phytoene to zeta-carotene. This result suggests that one polypeptide, the product of the pds gene, can carry out phytoene desaturation in the carotenoid biosynthetic pathway. Transcripts of the pds gene accumulate in orange tomato fruit, indicating transcriptional control of pds expression during fruit ripening. The deduced amino acid sequence of phytoene desaturase indicates that this enzyme in tomato contains 583 amino acids that are highly conserved with respect to the homologous enzymes in cyanobacteria and algae. The deduced amino acid sequences of the phytoene desaturases from other microorganisms (purple bacteria and fungi) appear to be evolutionarily unrelated to those from green photosynthetic organisms.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=49208Documentos Relacionados
- Tomato hydroxymethylglutaryl-CoA reductase is required early in fruit development but not during ripening.
- An Antisense Gene Stimulates Ethylene Hormone Production during Tomato Fruit Ripening.
- The cloning of two tomato lipoxygenase genes and their differential expression during fruit ripening.
- Reduction of tomato polygalacturonase beta subunit expression affects pectin solubilization and degradation during fruit ripening.
- Cloning of tomato (Lycopersicon esculentum Mill.) arginine decarboxylase gene and its expression during fruit ripening.