Abstract:
:In animals, fatty acid desaturases catalyze key reactions in the synthesis of arachidonic acid and other polyunsaturated fatty acids. A search of the Caenorhabditis elegans DNA databases, using the sequences of Arabidopsis genes, identified several putative desaturases. Here we describe the characterization of the first of these genes, fat-1. The predicted protein encoded by a fat-1 cDNA showed 32-35% identity with both FAD2 and FAD3 of Arabidopsis. When expressed in transgenic plants, fat-1 resulted in a 90% increase in the proportion of alpha-linolenic acid in root lipids. Wild-type Arabidopsis incorporated omega-6 fatty acids (delta8,11,14-20:3 and delta5,8,11,14-20:4) into membrane lipids but did not desaturate them. By contrast, fat-1 transgenic plants efficiently desaturated both of these fatty acids to the corresponding omega-3 products. These findings indicate that the C. elegans fat-1 gene encodes the first animal representative of a class of glycerolipid desaturases that have previously been characterized in plants and cyanobacteria. The FAT-1 protein is an omega-3 fatty acyl desaturase that recognizes a range of 18- and 20-carbon omega-6 substrates.
journal_name
Proc Natl Acad Sci U S Aauthors
Spychalla JP,Kinney AJ,Browse Jdoi
10.1073/pnas.94.4.1142subject
Has Abstractpub_date
1997-02-18 00:00:00pages
1142-7issue
4eissn
0027-8424issn
1091-6490journal_volume
94pub_type
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