A new cotton SDR family gene encodes a polypeptide possessing aldehyde reductase and 3-ketoacyl-CoA reductase activities
| Autor: | Wen-Qiang Song, Yu Pang, Yong-Mei Qin, Fang-Yuan Chen |
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| Rok vydání: | 2010 |
| Předmět: |
Molecular Sequence Data
Mutant Reductase Genes Plant Polymerase Chain Reaction Biochemistry Gas Chromatography-Mass Spectrometry Aldehyde Reductase Amino Acid Sequence Peptide sequence DNA Primers Alcohol dehydrogenase chemistry.chemical_classification Gossypium Base Sequence Sequence Homology Amino Acid biology General Medicine Molecular biology Amino acid Alcohol Oxidoreductases chemistry Biocatalysis 3-Oxoacyl-(Acyl-Carrier-Protein) Reductase biology.protein Fatty acid elongation |
| Zdroj: | Biochemistry (Moscow). 75:320-326 |
| ISSN: | 1608-3040 0006-2979 |
| DOI: | 10.1134/s0006297910030089 |
| Popis: | To understand regulatory mechanisms of cotton fiber development, microarray analysis has been performed for upland cotton (Gossypium hirsutum). Based on this, a cDNA (GhKCR3) encoding a polypeptide belonging to short-chain alcohol dehydrogenase/reductase family was isolated and cloned. It contains an open reading frame of 987 bp encoding a polypeptide of 328 amino acid residues. Following its overexpression in bacterial cells, the purified recombinant protein specifically uses NADPH to reduce a variety of short-chain aldehydes. A fragment between Gly180 and Gly191 was found to be essential for its catalytic activity. Though the GhKCR3 gene shares low sequence similarities to the ortholog of Saccharomyces cerevisiae YBR159w that encodes 3-ketoacyl-CoA reductase (KCR) catalyzing the second step of fatty acid elongation, it was surprisingly able to complement the yeast ybr159wDelta mutant. Gas chromatography-mass spectrometry analysis showed that very long-chain fatty acids, especially C26:0, were produced in the ybr159wDelta mutant cells expressing GhKCR3. Applying palmitoyl-CoA and malonyl-CoA as substrates, GhKCR3 showed KCR activity in vitro. Quantitative real time-PCR analysis indicated GhKCR3 transcripts accumulated in rapidly elongating fibers, roots, and stems. Our results suggest that GhKCR3 is probably a novel KCR contributing to very long-chain fatty acid biosynthesis in plants. |
| Databáze: | OpenAIRE |
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