Analysis of retrotransposition and DNA methylation in barley callus culture

Mature barley (Hordeum vulgare cv. Zafer-160) embryos were cultured on callus induction medium (MS+ 4 mg l-1 Dicamba) for 30 days and embryogenic calli were transferred onto regeneration medium (MS+ 0.5 mg l-1 trans-zeatin riboside). Callus induction percentage was 67.2%; embryogenic callus induction percentage was 42.3% and their regeneration percentage was 63.8%. Retrotransposon movements and methylation alterations in 15-day-old, 30-day-old calli and 4-day-old barley seedling (control) were investigated with Inter-Retrotransposon Amplified Polymorphism (IRAP) and Methylation-Sensitive Restriction Fingerprinting (MSRF), respectively. IRAP patterns were quite monomorphic however MSRF indicated increase in cytosine methylation during callus formation. Changes in retroelement movements and methylation alterations were evaluated and discussed in the light of literature.