Differential protein profiles in interspecific hybrids between Elaeis oleifera and E. guineensis with contrasting responses to somatic embryogenesis competence acquisition

Abstract

Understanding the molecular events that initiate somatic embryogenesis (SE) may help optimize clonal propagation protocols in oil palm. The objective of this work was to identify differentially abundant proteins during the induction of SE in two interspecific F1 hybrids of Elaeis oleifera × Elaeis guineensis with contrasting responses (responsive and non-responsive) to the SE process. Leaf explants were obtained and submitted to SE induction medium for up to 180 days. Explants were collected at 0, 14, 90 and 150 days of induction (doi). Proteins were extracted and analyzed by two-dimensional electrophoresis. Analyses were focused at 14 and 150 doi, representing the initial and late stages of embryogenic competence acquisition, respectively. The results indicate that at 14 doi a high amount of stress is present which results in cellular dedifferentiation. At 90 doi, cells (of the responsive genotype) seem adapted and have kept stress under control, allowing the use of energy for cellular proliferation that occurs at 150 doi. Therefore, the control of stress and oxidation seem to be crucial for callus development. We highlight proteins associated to oxidative stress, protein processing, energy metabolism and development as potentially involved in embryogenic competence acquisition.