Characterization of two cotton cDNAs encoding trans-2-enoyl-CoA reductase reveals a putative novel NADPH-binding motif
Very long chain fatty acids are important components of plant lipids, suberins, and cuticular waxes. Trans-2-enoyl-CoA reductase (ECR) catalyses the fourth reaction of fatty acid elongation, which is NADPH dependent. In the present study, the expression of two cotton ECR (GhECR) genes revealed by qu...
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Published in | Journal of experimental botany Vol. 60; no. 6; pp. 1839 - 1848 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Oxford
Oxford University Press
01.04.2009
Oxford Publishing Limited (England) |
Subjects | |
Online Access | Get full text |
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Summary: | Very long chain fatty acids are important components of plant lipids, suberins, and cuticular waxes. Trans-2-enoyl-CoA reductase (ECR) catalyses the fourth reaction of fatty acid elongation, which is NADPH dependent. In the present study, the expression of two cotton ECR (GhECR) genes revealed by quantitative RT-PCR analysis was up-regulated during cotton fibre elongation. GhECR1 and 2 each contain open reading frames of 933 bp in length, both encoding proteins consisting of 310 amino acid residues. GhECRs show 32% identity to Saccharomyces cerevisiae Tsc13p at the deduced amino acid level, and the GhECR genes were able to restore the viability of the S. cerevisiae haploid tsc13-deletion strain. A putative non-classical NADPH-binding site in GhECR was predicted by an empirical approach. Site-directed mutagenesis in combination with gas chromatography-mass spectrometry analysis suggests that G(5X)IPXG presents a putative novel NADPH-binding motif of the plant ECR family. The data suggest that both GhECR genes encode functional enzymes harbouring non-classical NADPH-binding sites at their C-termini, and are involved in fatty acid elongation during cotton fibre development. |
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Bibliography: | ark:/67375/HXZ-C31B3L9H-V istex:8FB09EA171998D3CB3A0F4287FF6A70420E9C279 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0022-0957 1460-2431 |
DOI: | 10.1093/jxb/erp057 |