title: Human acylation stimulating protein enhances triacylglycerol biosynthesis in plant microsomes.
abstract: Diacylglycerol acyltransferase has a universal role in catalyzing the acyl-CoA-dependent formation of triacylglycerol in microorganisms, animals and plants. Acylation stimulating protein, from human blood, is known to enhance diacylglycerol acyltransferase activity and triacylglycerol biosynthesis in human adipocytes. In the current study, acylation stimulating protein was also shown to enhance diacylglycerol acyltransferase activity in microsomes from cell suspension cultures of oilseed rape. Enzyme stimulation occurred over the pH range of 6-9 but the degree of stimulation decreased with increasing ionic strength at pH 7.4. Varying acyl-CoA concentration did not affect the degree of stimulation. Membranes from triacylglycerol producing cells in plants and humans may have similar binding sites for acylation stimulating protein which have been preserved during molecular evolution. The results suggest that human acylation stimulating protein may be useful in modifying lipid biosynthesis in plants.
authors.affiliation: Department of Chemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alta, Canada T1K 3M4. weselake@uleth.ca
authors.forename: R J
authors.initials: RJ
authors.lastname: Weselake
authors.forename: E C
authors.initials: EC
authors.lastname: Kazala
authors.forename: K
authors.initials: K
authors.lastname: Cianflone
authors.forename: D D
authors.initials: DD
authors.lastname: Boehr
authors.forename: C K
authors.initials: CK
authors.lastname: Middleton
authors.forename: C D
authors.initials: CD
authors.lastname: Rennie
authors.forename: A
authors.initials: A
authors.lastname: Laroche
authors.forename: I
authors.initials: I
authors.lastname: Recnik
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism / Q000494:pharmacology; D000217:Acyltransferases / Q000378:metabolism*; D001798:Blood Proteins / Q000494:pharmacology*; D001937:Brassica / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D002384:Catalysis / Q000187:drug effects; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D015926:Complement C3a / Q000031:analogs & derivatives*; D051048:Diacylglycerol O-Acyltransferase; D004305:Dose-Response Relationship, Drug; D019143:Evolution, Molecular; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008861:Microsomes / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D009994:Osmolar Concentration; D011189:Potassium Chloride / Q000494:pharmacology; D014280:Triglycerides / Q000096:biosynthesis*
chemical_list: D000214:Acyl Coenzyme A; D001798:Blood Proteins; D014280:Triglycerides; C044541:complement C3a, des-Arg-(77)-; C017585:oleoyl-coenzyme A; D011189:Potassium Chloride; D015926:Complement C3a; D000217:Acyltransferases; D051048:Diacylglycerol O-Acyltransferase