Genes for microsomal delta-12 fatty acid desaturases and hydroxylases from plants

Abstract

The preparation and use of nucleic acid fragments encoding fatty acid desaturase enzymes are described. The invention permits alteration of plant lipid composition. Chimeric genes incorporating such nucleic acid fragments with suitable regulatory sequences may be used to create transgenic plants with altered levels of unsaturated fatty acids.

1 - 18 . (canceled) 
     
     
         19 . A method for reducing polyunsaturated fatty acids in soybean oil comprising:
 (a) isolating a polynucleotide useful in antisense inhibition or sense suppression of an endogenous soybean delta-12 desaturase gene, wherein said soybean delta-12 desaturase gene encodes a soybean delta-12 desaturase polypeptide having at least 90% amino acid sequence identity to the polypeptide encoded by SEQ ID NO:5;   (b) making a cross between the following: (i) a soybean variety with increased oleic acid content or reduced linolenic acid content as compared to soybean variety Bonus; and (ii) a plant containing a chimeric gene comprising the isolated polynucleotide of step (a) operably linked, in a sense or antisense orientation, to at least one regulatory sequence;   (c) growing fertile plants from seeds obtained from the cross of step (b); and   (d) screening progeny seeds from the fertile plants of step (c) for seeds containing reduced polyunsaturated fatty acids as compared to soybean variety Bonus.   
     
     
         20 - 27 . (canceled) 
     
     
         28 . The method of  claim 19 , wherein the isolated polynucleotide of step (a) comprises a coding sequence. 
     
     
         29 . The method of  claim 19 , wherein the isolated polynucleotide of step (a) comprises a non-coding sequence. 
     
     
         30 . The method of  claim 19 , wherein the isolated polynucleotide of step (a) comprises both a coding and a non-coding sequence. 
     
     
         31 . The method of any one of  claim 19 ,  28 ,  29  or  30 , wherein the soybean variety with increased oleic acid content or reduced linolenic acid content is derived from at least one soybean variety selected from the group consisting of: N782245, A5, A23, A16 and C1640.