This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (44) Citing Articles via Google Scholar Google Scholar Articles by Cao, Y.-z. Articles by Huang, A. H. C. Search for Related Content PubMed PubMed Citation Articles by Cao, Y.-z. Articles by Huang, A. H. C. Agricola Articles by Cao, Y.-z. Articles by Huang, A. H. C.

Articles

Diacylglycerol Acyltransferase in Maturing Oil Seeds of Maize and Other Species ¹

Biology Department, University of South Carolina, Columbia, South Carolina 29208

Diacylglycerol acyltransferase (EC 2.3.1.20) activity was detected in the microsomal fractions of maturing maize scutellum, soybean cotyledon, peanut cotyledon, and castor bean endosperm. The activity detected was high enough to account for the in vivo rate of triacylglycerol synthesis. The activity of the maize enzyme was characterized using diolein micelles prepared by sonication in Tween 20 as the substrate. The activity was highest at pH values of 6 to 7. The activity was proportional to the amount of enzyme added, and the reaction rate was linear for about 2 minutes. The enzyme was not inactivated by Tween 20, Zwitterion 3-08, Triton-X 100, and cholate, but was inactivated completely by sodium dodecyl sulfate. The enzyme was active on linoleoyl coenzyme A (CoA), palmitoyl CoA, and oleoyl CoA, although the activity was highest on linoleoyl CoA. Endogenous diacylglycerol was present in the microsomes, and the enzyme activity was only partially dependent on the addition of external diolein. Subcellular fractionation of the total scutellum extract in sucrose density gradients was performed. By comparing the migration of the enzyme between rate and equilibrium centrifugation, and between equilibrium centrifugation in the presence and absence of magnesium ions in the preparative media, the enzyme was shown to be associated with the rough endoplasmic reticulum. Some of the above findings on the maize enzyme were extended to the enzymes from castor bean, soybean, and peanuts.

This article has been cited by other articles:

				J. M. Shockey, S. K. Gidda, D. C. Chapital, J.-C. Kuan, P. K. Dhanoa, J. M. Bland, S. J. Rothstein, R. T. Mullen, and J. M. Dyer Tung Tree DGAT1 and DGAT2 Have Nonredundant Functions in Triacylglycerol Biosynthesis and Are Localized to Different Subdomains of the Endoplasmic Reticulum PLANT CELL, September 1, 2006; 18(9): 2294 - 2313. [Abstract] [Full Text] [PDF]

				M. Waltermann and A. Steinbuchel Neutral Lipid Bodies in Prokaryotes: Recent Insights into Structure, Formation, and Relationship to Eukaryotic Lipid Depots J. Bacteriol., June 1, 2005; 187(11): 3607 - 3619. [Full Text] [PDF]

				K. Hsieh and A. H.C. Huang Endoplasmic Reticulum, Oleosins, and Oils in Seeds and Tapetum Cells Plant Physiology, November 1, 2004; 136(3): 3427 - 3434. [Full Text] [PDF]

				C. Jako, A. Kumar, Y. Wei, J. Zou, D. L. Barton, E. M. Giblin, P. S. Covello, and D. C. Taylor Seed-Specific Over-Expression of an Arabidopsis cDNA Encoding a Diacylglycerol Acyltransferase Enhances Seed Oil Content and Seed Weight Plant Physiology, June 1, 2001; 126(2): 861 - 874. [Abstract] [Full Text] [PDF]

				X. Bao and J. Ohlrogge Supply of Fatty Acid Is One Limiting Factor in the Accumulation of Triacylglycerol in Developing Embryos Plant Physiology, August 1, 1999; 120(4): 1057 - 1062. [Abstract] [Full Text]