Variations in genomic DNA methylation during the long-term in vitro proliferation of oil palm embryogenic suspension cultures
The long-term proliferation of embryogenic cell suspensions of oil palm is associated with changes in both genomic methylation rates and embryogenic capacities.
In the aim of exploring the relationship between epigenetic stability and the long-term in vitro proliferation of plant tissues, we have studied changes in genomic DNA methylation levels in embryogenic suspensions of oil palm (Elaeis guineensis Jacq.). Five embryogenic callus lines were obtained from selected hybrid seeds and then proliferated as suspension cultures. Each clonal line obtained from a single genotype was subdivided into three independent subclonal lines. Once established, cultures proliferated for 12 months and genomic DNA was sampled at 4 months intervals for the estimation of global DNA methylation rates through high performance liquid chromatography (HPLC) quantitation of deoxynucleosides. Our results show that in vitro proliferation induces DNA hypermethylation in a time-dependent fashion. Moreover, this trend is statistically significant in several clonal lines and shared between subclonal lines originating from the same genotype. Interestingly, the only clonal line undergoing loss of genomic methylation in the course of proliferation has been found unable to generate somatic embryos. We discuss the possible implications of genome-wide DNA methylation changes in proliferating cells with a view to the maintenance of genomic and epigenomic stability.
KeywordsArecaceae DNA methylation Elaeis guineensis Epigenetic stability Somaclonal variation Somatic embryogenesis
Global Methylation Rate
High Performance Liquid Chromatography
Plant Growth Regulator
- Cochard B, Amblard P, Durand-Gasselin T (2005) Oil palm genetic improvement and sustainable development. Oléagineux Corps gras Lipides 12:141–147Google Scholar
- Kramut P, Te-chato S (2010) Effect of culture media, plant growth regulators and carbon sources on establishment of somatic embryo in suspension culture of oil palm. J Agri Technol 6:159–170Google Scholar
- Pannetier C, Arthuis P, Lievoux D (1981) Néoformation de jeunes plantes d’Elaeis guineensis à partir de cals primaires obtenus sur fragments foliaires cultivés in vitro. Oléagineux 36:119–122Google Scholar
- Reuveni O, Israeli Y (1990) Measures to reduce somaclonal variation in in vitro propagated bananas. Acta Horticulturae 275:307–314Google Scholar
- Rival A, Jaligot E (2011) Epigenetics and plant breeding. CAB reviews: perspectives in agriculture, veterinary science, nutrition and natural resources 6:048Google Scholar