This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 18/3/665    most recent tpc.105.040543v1 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 ISI 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 ISI Web of Science (11) Citing Articles via Google Scholar Google Scholar Articles by Eastmond, P. J. Search for Related Content PubMed PubMed Citation Articles by Eastmond, P. J. Agricola Articles by Eastmond, P. J.

SUGAR-DEPENDENT1 Encodes a Patatin Domain Triacylglycerol Lipase That Initiates Storage Oil Breakdown in Germinating Arabidopsis Seeds^[W]

Department of Biology, Centre for Novel Agricultural Products, University of York, York YO10 5YW, United Kingdom

¹ To whom correspondence should be addressed. E-mail pje4{at}york.ac.uk; fax 44-01904-328762.

Triacylglycerol hydrolysis (lipolysis) plays a pivotal role in the life cycle of many plants by providing the carbon skeletons and energy that drive postgerminative growth. Despite the physiological importance of this process, the molecular mechanism is unknown. Here, a genetic screen has been used to identify Arabidopsis thaliana mutants that exhibit a postgerminative growth arrest phenotype, which can be rescued by providing sugar. Seventeen sugar-dependent (sdp) mutants were isolated, and six represent new loci. Triacylglycerol hydrolase assays showed that sdp1, sdp2, and sdp3 seedlings are deficient specifically in the lipase activity that is associated with purified oil bodies. Map-based cloning of SDP1 revealed that it encodes a protein with a patatin-like acyl-hydrolase domain. SDP1 shares this domain with yeast triacylglycerol lipase 3 and human adipose triglyceride lipase. In vitro assays confirmed that recombinant SDP1 hydrolyzes triacylglycerols and diacylglycerols but not monoacylglycerols, phospholipids, galactolipids, or cholesterol esters. SDP1 is expressed predominantly in developing seeds, and a SDP1–green fluorescent protein fusion was shown to associate with the oil body surface in vivo. These data shed light on the mechanism of lipolysis in plants and establish that a central component is evolutionarily conserved among eukaryotes.

This article has been cited by other articles:

				A.-L. Quettier, E. Shaw, and P. J. Eastmond SUGAR-DEPENDENT6 Encodes a Mitochondrial Flavin Adenine Dinucleotide-Dependent Glycerol-3-P Dehydrogenase, Which Is Required for Glycerol Catabolism and Postgerminative Seedling Growth in Arabidopsis Plant Physiology, September 1, 2008; 148(1): 519 - 528. [Abstract] [Full Text] [PDF]

				S. Footitt, D. Dietrich, A. Fait, A. R. Fernie, M. J. Holdsworth, A. Baker, and F. L. Theodoulou The COMATOSE ATP-Binding Cassette Transporter Is Required for Full Fertility in Arabidopsis Plant Physiology, July 1, 2007; 144(3): 1467 - 1480. [Abstract] [Full Text] [PDF]

				P. O'Hara, A. R. Slabas, and T. Fawcett Antisense Expression of 3-Oxoacyl-ACP Reductase Affects Whole Plant Productivity and Causes Collateral Changes in Activity of Fatty Acid Synthase Components Plant Cell Physiol., May 1, 2007; 48(5): 736 - 744. [Abstract] [Full Text] [PDF]

				P. J. Eastmond MONODEHYROASCORBATE REDUCTASE4 Is Required for Seed Storage Oil Hydrolysis and Postgerminative Growth in Arabidopsis PLANT CELL, April 1, 2007; 19(4): 1376 - 1387. [Abstract] [Full Text] [PDF]