Somatic embryogenesis and mass spectrometric identification of proteins related to somatic embryogenesis in Eruca sativa

Several different proteins expressed in embryogenic and nonembryogenic Eruca sativa calli were identified by combining one-dimensional SDS-PAGE protein mapping with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. By querying the widely recognized MASCOT search engine, it was found that three of the proteins that were particularly strongly expressed in the embryogenic callus represented sucrose synthase, phospholipase D, and enolase, respectively. RT-PCR analysis also confirmed that the gene coding for enolase was transcribed especially strongly in the embryogenic callus but not in nonembyogenic callus. Finally, the relationship between the three proteins and somatic embryogenesis is discussed.