cDNA-AFLP analysis of transcript derived fragments during seed development in castor bean (Ricinus communis L.)

Ricinoleic acid, one of the biggest components in castor oil, is an unusual fatty acid with numerous industrial applications. Despite much research on the oil content of Ricinus communis L., the genes encoding the oil biosynthesis function in the seed developmental stages are still poorly known. Here, we analyzed differentially expressed transcripts during seed development using cDNA-amplified fragment length polymorphism. Almost all ingredients significantly decreased along with seed maturation, except for ricinoleic acid, which increased greatly from 6.7% to 86.8%. A total of 534 distinguished fragments were differentially expressed in six development stages. Among these, 67 fragments showed high homology with known-function genes, and 26 sequences were successfully annotated with fatty acid synthesis or storage proteins in castor and other species. The results showed that fatty acid synthesis and accumulation in castor seeds displayed various temporal patterns. Different cDNA-fragment patterns were mainly found in later development stages, coinciding with the onset of oil synthesis.