Co-regulation of a gene homologous to early light-induced genes in higher plants and beta-carotene biosynthesis in the alga Dunaliella bardawil.

摘要: Dunaliella bardawil, a unicellular green alga that can be induced to accumulate massive amounts of beta-carotene, is particularly suitable for studies carotenogenesis regulation and its links developmental adaptive processes in the chloroplast. A cDNA clone corresponding transcript accumulating coordinately with induction was isolated by differential hybridization library made from intensely illuminated cells. This also abundant algal mutants able beta-carotene under relatively low light intensity. DNA sequence analysis indicates cbr (for carotene biosynthesis-related) closely related early light-induced genes (elip) higher plants. Similarity exists between repeated oligopeptide motifs Cbr Cab proteins photosystems I II. Three upstream direct repeats include an octamer hexamer mammalian sterol regulatory elements. The relationship accumulation, structural similarity proteins, presence potential SRE-1 elements lead us propose represents novel carotenoid binding whose synthesis might coordinated carotenogenic enzymes via evolutionary conserved mechanism.