Molecular and functional characterization of a cDNA encoding 4-hydroxy-3-methylbut-2-enyl diphosphate reductase from Dunaliella salina.
In green algae, the final step of the plastidial methylerythritol phosphate (MEP) pathway is catalyzed by 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR; EC: 1.17.1.2), an enzyme proposed to play a key role in the regulation of isoprenoid biosynthesis. Here we report the isolation and functional characterization of a 1959-bp Dunaliella salina HDR (DsHDR) cDNA encoding a deduced polypeptide of 474 amino acid residues. Phylogenetic analysis implied a cyanobacterial origin for plant and algal HDR genes. Steady-state DsHDR transcript levels were higher in D. salina cells submitted to nutritional depletion, high salt and/or high light, suggesting that DsHDR may respond to the same environmental cues as genes involved in carotenoid biosynthesis.
Ramos
Ana A
AA
Centre of Marine Sciences, University of Algarve, Campus de Gambelas, Faro 8005-139, Portugal.
Marques
Ana R
AR
Rodrigues
Marta
M
Henriques
Nuno
N
Baumgartner
Alexandra
A
Castilho
Rita
R
Brenig
Bertram
B
Varela
João C
JC
D020418:Algal Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D015152:Blotting, Northern; D000460:Chlorophyta / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
D020418:Algal Proteins; D018076:DNA, Complementary; D010088:Oxidoreductases