Expression and properties of diacylglycerol acyltransferase from cell-suspension cultures of oilseed rape.
The expression of diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) with predicted molecular mass of 56.9. kDa (BnDGAT1) was examined using microspore-derived cell suspension cultures of oilseed rape (Brassica napus L. cv Jet Neuf). As well, a recombinant histidine-tagged N-terminal fragment of BnDGAT1 [BnDGAT1((1-116))His(6)], which was relatively hydrophilic, was partially characterized. A temporal increase in DGAT activity occurred within a 24 h period following transfer of cells from 6% (w/v) sucrose to 14% (w/v) sucrose. Western blotting indicated that the abundance of BnDGAT1 protein was closely correlated with DGAT activity. BnDGAT1 mRNA also exhibited a temporal increase within the 24 h period following transfer of cells into higher sucrose concentrations, but the transcript level was not closely associated with DGAT activity as BnDGAT1 protein. The fragment BnDGAT1(1-116)His(6) interacted with [1-(14)C]oleoyl-CoA, suggesting that the N-terminal region of BnDGAT1 may have a role in binding cellular acyl-CoA.
Weselake
R J
RJ
Department of Chemistry and Biochemistry, University of Lethbridge, Alberta T1K 3M4, Canada.
Nykiforuk
C L
CL
Laroche
A
A
Patterson
N A
NA
Wiehler
W B
WB
Szarka
S J
SJ
Moloney
M M
MM
Tari
L W
LW
Derekh
U
U
D000214:Acyl Coenzyme A / Q000378:metabolism; D000217:Acyltransferases / Q000235:genetics* / Q000378:metabolism*; D001937:Brassica / Q000166:cytology / Q000201:enzymology*; D002478:Cells, Cultured; D051048:Diacylglycerol O-Acyltransferase; D007700:Kinetics; D014176:Protein Biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D013997:Time Factors; D014158:Transcription, Genetic
D000214:Acyl Coenzyme A; D011994:Recombinant Proteins; C017585:oleoyl-coenzyme A; D000217:Acyltransferases; D051048:Diacylglycerol O-Acyltransferase