Modification of Brassica seed oil by antisense expression of a stearoyl-acyl carrier protein desaturase gene.
Molecular gene transfer techniques have been used to engineer the fatty acid composition of Brassica rapa and Brassica napus (canola) oil. Stearoyl-acyl carrier protein (stearoyl-ACP) desaturase (EC 1.14.99.6) catalyzes the first desaturation step in seed oil biosynthesis, converting stearoyl-ACP to oleoyl-ACP. Seed-specific antisense gene constructs of B. rapa stearoyl-ACP desaturase were used to reduce the protein concentration and enzyme activity of stearoyl-ACP desaturase in developing rapeseed embryos during storage lipid biosynthesis. The resulting transgenic plants showed dramatically increased stearate levels in the seeds. A continuous distribution of stearate levels from 2% to 40% was observed in seeds of a transgenic B. napus plant, illustrating the potential to engineer specialized seed oil compositions.
Knutzon
D S
DS
Calgene, Inc., Davis, CA 95616.
Thompson
G A
GA
Radke
S E
SE
Johnson
W B
WB
Knauf
V C
VC
Kridl
J C
JC
D001483:Base Sequence; D001937:Brassica / Q000235:genetics* / Q000254:growth & development; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D005818:Genetic Engineering; D007612:Kanamycin / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010938:Plant Oils / Q000378:metabolism*; D016372:RNA, Antisense; D012333:RNA, Messenger / Q000235:genetics; D013228:Stearates / Q000378:metabolism
D010938:Plant Oils; D016372:RNA, Antisense; D012333:RNA, Messenger; D013228:Stearates; D007612:Kanamycin; D004247:DNA; D006899:Mixed Function Oxygenases; C018747:acyl-(acyl-carrier-protein)desaturase