Plant fatty acid desaturases and alleles therefor

A recombinant nucleic acid encoding a plant fatty acid desaturase, wherein the nucleic acid sequence encodes an amino acid substitution in the desaturaseat a position selected from the group consisting of:

• a position in the motif STTCWSIMLAT;
• a position in the motif STTCWSIMLATcorresponding to positions 210 to 220 of Apollo Fad3A;
• a position in the motif STTCWSIMLATLVYLSFL;
• a position in the motif STTCWSIMLATLVYLSFL corresponding to positions 210 to 227 of Apollo Fad3A;
• a position in the motif SYLRGGLTTIDRD;
• a position in the motif SYLRGGLTTIDRD corresponding to positions 272 to 284 of Apollo Fad3A;
• a position in the motif SXXXDHYVSD;
• and a position in the motif SXXXDHYVSD beginning at a position corresponding to position 347 of Apollo Fad3A.

A method of plant selection comprising:

• a) obtaining a progeny plant by (i) transformation of a parent plant, (ii) crossing parent plant lines or (iii) self crossing of the parent plant;
• and,
• b) identifying in the progeny plants a nucleic acid encoding a plant fatty acid desaturase, wherein the nucleic acid encodes an amino acid in the desaturase selected from the group consisting of:
• i) an amino acid other than cysteine at an amino acid position corresponding to amino acid 213 of Apollo Fad3A;
• ii) an amino acid other than arginine at an amino acid position corresponding to amino acid 275 of Apollo Fad3A;
• iii) an amino acid other than serine at an amino acid position corresponding to amino acid 347 of Apollo Fad3A;
• iv) an amino acid other than methionine at an amino acid position corresponding to amino acid 217 of Apollo Fad3A;
• v) an amino acid other than isoleucine at an amino acid position corresponding to amino acid 281 of Apollo Fad3A;
• and,
• vi) an amino acid other than leucine at an amino acid position corresponding to amino acid 224 of Apollo Fad3A.

A method of plant selection comprising:

• a) obtaining a progeny plant by:
• (i) transformation of a parent plant, (ii) crossing parent plant lines or (iii) self crossing of the parent plant;
• and,
• b) identifying in the progeny plants a nucleic acid encoding a plant fatty acid desaturase, wherein the nucleic acid encodes an amino acid in the desaturase selected from the group consisting of:
• i) a non-conserved amino acid substituted in the motif STTCWSIM;
• ii) a non-conserved amino acid substituted in the motif STTCWSIM centered on a position corresponding to position 213 of Apollo Fad3A;
• iii) a non-conserved amino acid substituted in the motif SYLRGGL;
• iv) a non-conserved amino acid substituted in the motif SYLRGGL centered on a position corresponding to position 275 of Apollo Fad3A;
• v) a non-conserved amino acid substituted in the motif SXXXDHYVSD;
• vi) a non-conserved amino acid substituted in the motif SXXXDHYVSD beginning at a position corresponding to position 347 of Apollo Fad3A;
• vii) a non-conserved amino acid substituted in the motif STTCWSIMLAT;
• viii) a non-conserved amino acid substituted in the motif STTCWSIMLAT corresponding to positions 210 to 220 of Apollo Fad3A;
• ix) a non-conserved amino acid substituted in the motif SYLRGGLTTIDRD;
• x) a non-conserved amino acid substituted in the motif SYLRGGLTTIDRD corresponding to positions 272 to 284 of Apollo Fad3A.

An isolated plant Fad3 enzyme having an amino acid residue selected from the group consisting of:

• i) an amino acid other than cysteine at an amino acid position corresponding to amino acid 213 of Apollo Fad3A;
• ii) an amino acid other than arginine at an amino acid position corresponding to amino acid 275 of Apollo Fad3A;
• iii) an amino acid other than serine at an amino acid position corresponding to amino acid 347 of Apollo Fad3A;
• iv) an amino acid other than methionine at an amino acid position corresponding to amino acid 217 of Apollo Fad3A;
• v) an amino acid other than isoleucine at an amino acid position corresponding to amino acid 281 of Apollo Fad3A;
• and, vi) an amino acid other than leucine at an amino acid position corresponding to amino acid 224 of Apollo Fad3A.