Our next Friday Seminar takes place in the Merton Auditorium at 11:30am on Friday 6 September.

Speaker

Dr Frederic Berger, Gregor Mendel Institute of Molecular Plant Biology

Title

‘How to drive the plant life cycle with a single lysine residue‘

Synopsis

Patterns of gene expression through the cell cycle requires prompt restoration of epigenetic marks after the dilution caused by DNA replication.

The Berger lab have shown that the variant H3.1 is essential for maintenance and propagation of the transcriptional repressive mark histone H3 lysine 27 trimethylation (H3K27me3) including the flowering time controller locus FLC, illustrating the important role played by histone variants in epigenetic regulation of transcription (Jiang and Berger, 2017).

In contrast with the maintenance of H3K27me3 by H3.1, the non-replicative variant H3.3 is involved in reprogramming epigenetic marks in animals. However, it remains unclear when and how chromatin marks are reprogrammed during plant development on loci that undergo a cyclic activity like FLC.

In Arabidopsis, they’ve shown that the epigenetic mark H3K27me3 is selectively removed from sperm chromatin through a multi-layered mechanism, which includes deposition of a sperm-specific histone H3 variant that is immune to lysine 27 methylation. The resulting loss of H3K27me3 coincides with establishment of active states that prime gene expression not only during spermatogenesis but also in the next generation, revealing novel cycles of genome-wide reprogramming that guide early plant life.

Dr Frederic Berger biography

Research during Frederic’s PhD and Post-Doc led to recognise the importance of the cell wall for determination of cell fate.

Early career as PI led to establish that see size is established by endosperm growth and its regulation by growth of maternal components of the seed, a concept that as proven true later for all seeds.

Mid-career research focused on fertilization mechanisms. This led to unravel the dynamics of cytoskeleton and chromatin during fertilization and emerging interest in histone variants

Since 2007, Berger group pioneered work on the role of histone variants and discovered new types of H2A variants. This work has placed his group at the forefront of research in this field of chromatin dynamics.