These authors contributed equally to this work.
Comparative deep transcriptional profiling of four developing oilseeds
Article first published online: 10 OCT 2011
© 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd
The Plant Journal
Volume 68, Issue 6, pages 1014–1027, December 2011
How to Cite
Troncoso-Ponce, M. A., Kilaru, A., Cao, X., Durrett, T. P., Fan, J., Jensen, J. K., Thrower, N. A., Pauly, M., Wilkerson, C. and Ohlrogge, J. B. (2011), Comparative deep transcriptional profiling of four developing oilseeds. The Plant Journal, 68: 1014–1027. doi: 10.1111/j.1365-313X.2011.04751.x
- Issue published online: 13 DEC 2011
- Article first published online: 10 OCT 2011
- Accepted manuscript online: 18 AUG 2011 02:49PM EST
- Received 7 June 2011; revised 12 August 2011; accepted 16 August 2011; published online 10 October 2011.
- lipid metabolism;
- triacylglycerol synthesis;
- fatty acid biosynthesis;
- expressed sequence tags;
- comparative transcriptomics
Transcriptome analysis based on deep expressed sequence tag (EST) sequencing allows quantitative comparisons of gene expression across multiple species. Using pyrosequencing, we generated over 7 million ESTs from four stages of developing seeds of Ricinus communis, Brassica napus, Euonymus alatus and Tropaeolum majus, which differ in their storage tissue for oil, their ability to photosynthesize and in the structure and content of their triacylglycerols (TAG). The larger number of ESTs in these 16 datasets provided reliable estimates of the expression of acyltransferases and other enzymes expressed at low levels. Analysis of EST levels from these oilseeds revealed both conserved and distinct species-specific expression patterns for genes involved in the synthesis of glycerolipids and their precursors. Independent of the species and tissue type, ESTs for core fatty acid synthesis enzymes maintained a conserved stoichiometry and a strong correlation in temporal profiles throughout seed development. However, ESTs associated with non-plastid enzymes of oil biosynthesis displayed dissimilar temporal patterns indicative of different regulation. The EST levels for several genes potentially involved in accumulation of unusual TAG structures were distinct. Comparison of expression of members from multi-gene families allowed the identification of specific isoforms with conserved function in oil biosynthesis. In all four oilseeds, ESTs for Rubisco were present, suggesting its possible role in carbon metabolism, irrespective of light availability. Together, these data provide a resource for use in comparative and functional genomics of diverse oilseeds. Expression data for more than 350 genes encoding enzymes and proteins involved in lipid metabolism are available at the ‘ARALIP’ website (http://aralip.plantbiology.msu.edu/).