Expression profiles of genes involved in fatty acid and triacylglycerol synthesis in developing seeds of Jatropha (Jatropha curcas L.)

Jatropha (Jatropha curcas L., Euphorbiaceae), a potential biodiesel plant, has created tremendous interest all over the world for the use of its seed oil as a commercial source of biodiesel. Due to the unreliability of oil content in its seeds and low economic returns planting of jatropha in agriculture was restricted. Investigating the molecular basis of storage lipid accumulation during seed development is an immediate need to understand genetic factors regulating storage lipid biosynthesis in jatropha seeds. In this study, we characterized the seed development and lipid accumulation from female flowers pollinated to mature seeds, and investigated temporal expression profiles of 21 lipid genes involved in different steps of the pathways leading to fatty acid and TAG synthesis within jatropha developing seeds using quantitative real-time PCR technology. Concomitantly, 17 genes increased their expression levels in developing seeds compared to their expression in leaf, but showed various temporal expression patterns and different relative-maximum ratio ranging from 2.8 to 1,919,280-fold in developing seeds. Five gene groups with distinct temporal patterns were identified by clustering analysis of expression data. Two gene groups including 15 genes presented up-regulated expression patterns correlated with storage lipid accumulation in developing seeds. This study provided not only the initial information on promoter activity for each gene, but also a first glimpse of the global patterns of gene expression and regulation, which are critical to understand the molecular basis of lipid biosyntheses, identifying the rate-limiting genes during seed development and to create improved varieties by genetic engineering. (C) 2011 Elsevier Ltd. All rights reserved.