Immunocytological localization of two plant fatty acid desaturases in the endoplasmic reticulum.
The subcellular location of two integral membrane-bound fatty acid desaturases (Fads), Fad2 and Fad3, was elucidated by immunofluorescence microscopic analyses of tobacco suspension cells transiently transformed with different epitope-tagged versions of the enzymes. Both myc- or hemagglutinin-tagged Fad2 and Fad3 localized to the same region of the endoplasmic reticulum (ER), as evidenced by their co-localization with the ER lumenal protein calreticulin. Results from differential permeabilization experiments revealed that the N-termini of both epitope-tagged Fad2 and Fad3 were exposed on the cytosolic side of ER membranes. These data define the subcellular location and topological orientation of plant desaturases in ER membranes.
Dyer
J M
JM
USDA-ARS Southern Regional Research Center, New Orleans, LA 70124, USA. jdyer@nola.srrc.usda.gov
Mullen
R T
RT
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D001937:Brassica / Q000201:enzymology / Q000235:genetics; D002478:Cells, Cultured; D003600:Cytosol / Q000201:enzymology; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D044943:Fatty Acid Desaturases / Q000032:analysis* / Q000235:genetics; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods; D010947:Plants, Toxic; D014026:Nicotiana / Q000201:enzymology
D044943:Fatty Acid Desaturases; C040448:delta-12 fatty acid desaturase; C078565:omega-3 fatty acid desaturase