Abstract
Microsomal membrane preparations from the developing cotyledons of safflower (Carthamus tinctorius L.) seed catalyse the formation of triacylglycerol fromsn-glycerol 3-phosphate and linoleoyl-CoA. Conditions of incubation were achieved in which the rate of triacylglycerol synthesis approached activities which were compatible with oil accumulation observed in vivo. Reaction mixtures which contained the microsomes took on a white soup-like appearance as triacylglycerol synthesis proceeded and sufficient oil was produced to form a white fat-pad at the surface after centrifugation. The development of the oil bodies in the microsomal membranes was studied by electron microscopy and showed that lipid droplets were formed in or on the membrane surface and were then released as apparently naked entities into the surrounding medium. The ontogeny of the oil droplet in vitro is discussed in terms of oil-body formation in vivo.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bergfeld, R., Hong, Y-N., Kühnl, T., Schopfer, P. (1978) Formation of oleosomes (storage lipid bodies) during embryogenesis and their breakdown during development in cotyledons ofSinapsis alba L. Planta143, 297–307
Bligh, E.G., Dyer, W.J. (1959) A rapid method of total lipid extraction and purification. Can. J. Biochem. Physiol.37, 911–917
Frey-Wyssling, A., Grieshaber, E., Mühlethaler, K. (1963) Origin of spherosomes in plant cells. J. Ultrastruct. Res.8, 506–516
Griffiths, G., Stobart, A.K., Stymne, S. (1985) The acylation ofsn-glycerol 3-phosphate and the metabolism of phosphatidate in microsomal preparations from the developing cotyledons of safflower (Carthamus tinctorius L.) seed. Biochem. J.230, 379–388
Harwood, J.L., Sodja, A., Stumpf, P.K. (1971) On the origin of oil droplets in maturating castor bean seeds,Ricinus communis L. Lipids6, 851–854
Höglund, S. (1980) Electron microscopic methods of investigating membrane and virus structure. In: Blough, H.A., Tiffany, J.M. (eds) Cell membranes and viral-envelopes, vol. 1, pp. 8–69. Academic Press, London
Kleinig, H., Steinki, C., Kopp, C., Zaar, K. (1978) Oleosomes (Spherosomes) fromDaucas carota suspension culture cells. Planta140, 233–237
Rest, J.A., Vaughan, J.G. (1972) The development of protein and oil bodies in the seed ofSinapsis alba I. Planta105, 245–262
Sanchez, M., Nicholls, D.G., Brindley, D.N. (1973) The relationship between palmitoyl-CoA synthetase activity and esterification ofsn-glycerol 3-phosphate in rat liver mitochondria. Biochem. J.132, 697–706
Slack, C.R., Bertaud, W.S., Shaw, B.D., Holland, R., Browse, J., Wright, H. (1980) Some studies on the composition and surface properties of oil bodies from the seed cotyledons of safflower and linseed. Biochem. J.190, 551–561
Slack, C.R., Browse, J.A. (1984) Synthesis of storage lipids in developing seeds. In: Murray, D.R. (ed) Seed physiology, vol. 1, pp. 209–243. Academic Press, Sydney London New York
Slack, C.R., Roughan, P.G., Browse, J.A., Gardiner, S.E. (1985) Some properties of cholinephosphotransferase from developing safflower cotyledons. Biochim. Biophys. Acta833, 438–448
Stobart, A.K., Stymne, S. (1985a) The regulation of the fatty-acid composition of the triacylglycerols in microsomal preparations from avocado mesocarp and the developing cotyledons of safflower. Planta163, 119–125
Stobart, A.K., Stymne, S. (1985b) The interconversion of diacylglycerol and phosphatidylcholine during triacylglycerol production in microsomal preparations of developing cotyledons of safflower (Carthamus tinctorius L.). Biochem. J.232, 217–221
Stymne, S., Stobart, A.K. (1984a) The biosynthesis of triacylglycerols in microsomal preparations of developing cotyledons of sunflower. Biochem. J.220, 481–488
Stymne, S., Stobart, A.K. (1984b) Evidence for the reversibility of the acyl-CoA: lysophosphatidylcholine acyltransferase in the microsomes of developing safflower cotyledons and rat liver. Biochem. J.223, 305–314
Stymne, S., Stobart, A.K. (1985) Oil synthesis in-vitro in microsomal membranes from developing cotyledons ofLinum usitatissimum L. Planta164, 101–104
Stymne, S., Stobart, A.K., Glad, G. (1983) The role of the acyl-CoA pool in the synthesis of polyunsaturated 18-carbon fatty acids and triacylglycerol production in the microsomes of developing safflower seeds. Biochim. Biophys. Acta752, 198–208
Wanner, G., Theimer, R.R. (1978) Membranous appendices of spherosomes (oleosomes). Possible role in fat utilization in germinating oil seeds. Planta140, 163–169
Wanner, G., Tormanek, H., Theimer, R.R. (1981) The ontogeny of lipid bodies (spherosomes) in plant cells. Planta151, 109–123
Yatsu, L.Y., Jacks, T.J. (1972) Spherosome membranes. Plant Physiol.49, 937–943
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Stobart, A.K., Stymne, S. & Höglund, S. Safflower microsomes catalyse oil accumulation in vitro: A model system. Planta 169, 33–37 (1986). https://doi.org/10.1007/BF01369772
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01369772