Fatty acid desaturase genes

Fig. 4. Modification of plant metabolic pathways for the synthesis of poly(3HAMCL) in peroxisomes. The pathways created or enhanced by the expression of transgenes (P. aeruginosa PHA synthase and C. lanceolata decanoyl-ACP thioesterase) and of mutant alleles of plant fatty acid desaturase genes are highlighted by bold arrows and the enzymes involved underlined...

Wicker-Thomas C., Henriet C. and Dallerac R. (1997) Partial characterization of a fatty acid desaturase gene in Drosophila melanogaster. Insect Biochem. Molec. Biol. 27, 963-972. 

Fujiwara, D., Yoshimoto, FI., Sone, FI., Flarashima, S. and Tamai, Y. Transcriptional coregulation of Saccharomyces cerevisiae alcohol acetyltransferase gene, ATFl and delta-9 fatty acid desaturase gene, OLEl by unsaturated fatty acids. Yeast 14 (1998), 711-721. 

Sakamoto, T. and Bryant, D.A. Temperature-regulated mRNA accumulation and stabilization for fatty acid desaturase genes in the cyanobacterium Synechococcus sp. strain PCC 7002. Mol Microbiol, 23 (1997)1281-1292. 

Michaelson, L.V., Lazarus, C.M., Griffiths, G., Napier, J.A., and Stobart, A.K. 1998. Isolation of a A -fatty acid desaturase gene from Mortierella alpina, J. Plant Biochem., 30, 19055-19059. 

Wakita Y, Otani M, Hamada T, Mori M, Iba K, Shimada T (2001) A tobacco mirmrsomal 00-3 fatty acid desaturase gene increases the linolenic acid content in transgenic sweet potato (Ipomoea batatas). Plant Cell Rept 20 244—249... 

Banik, M., Duguid, S., Cloutier, S., 2011. Transcript profiling and gene characterization of three fatty acid desaturase genes in high, moderate, and low linolenic acid genotypes of flax Unum usitatissium L.) and their role in linolenic acid accumulation. Genome 54, 471-483. 

Stukey J. E., McDonough V. M. and Martin C. E., (1990) The OLE1 gene of Saccharomyces cerevisiae encodes the A9 fatty acid desaturase and can be functionally replaced by the rat stearoyl-CoA desaturase gene. J. Biol. Chem. 265, 20144-20149. 

Additionally, the study demonstrated that there are fatty acid metabolism genes that were positively associated with lovastatin production and tended to encode catabolic enzymes that are predicted to promote formation of the polyketide precursors acetyl-CoA and malonyl-CoA, whereas fatty acid metabolism genes that are negatively associated with secondary metabolite production encode anabolic enzymes, i.e., acyl-CoA oxidase, fatty acid desaturase, and fatty acid synthases. 

Apart from the above mentioned enzymes, there also exist a few enzymes involved in PUFA metabolic pathways that have recently been found. One of them is a novel n-3 fatty acid desaturase, isolated from an EPA-rich fungus, Saprolegnia diclina [248]. The gene was isolated by PCR amplification from a fungus cDNA library and then, expressed in S. cerevisiae, which was cultured in the presence of several FA as substrates. The study showed that the recombinant protein could exclusively desaturase C20 n-6 PUFAs, with preference for AA which was converted into EPA. This represents a completely novel and different activity from any organism previously described, and its potential for use in EPA production in transgenic oilseed crops has been outlined. 

Nakamura MT, Cho HP, Clarke SD. Regulation of hepatic delta-6 desaturase expression and its role in the polyunsaturated fatty acid inhibition of fatty acid synthase gene expression in mice. J Nutr 2000 30 1561-1565. 

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