FBS Colloquia No.162Chromosome Function and Regulation Laboratory
| Seminar or Lecture |
The new role of H3K9 methyltransferase complex Kei Kawakami [Chromosome Function and Regulation Laboratory] Subnuclear localization-dependent restriction of centromere propagation Kojiro Ishii [Chromosome Function and Regulation Laboratory] |
|---|---|
| Date and Time | Wednesday, May 31, 2017, 12:15-13:00 |
| Place | 2F Seminar room, BioSystems Building |
| Contact |
Kojiro Ishii |
The new role of H3K9 methyltransferase complex
Eukaryotic chromosome is composed of two types of chromatin structures, euchromatin and heterochromatin. Heterochromatin is a higher order chromatin structure repressing the gene expression characterized by methylated Lys9 in histone H3 (H3K9me). Here we found that histone H3K9 methyltransferase complex functions as an ubiquitin E3 ligase complex to degrade H3K9 demethylase in addition to its canonical H3K9 metyltransferase activity. We will discuss about the model that H3K9me complex degrades H3K9 demethylase to facilitate heterochromatin assembly.
Subnuclear localization-dependent restriction of centromere propagation
Stable genome inheritance requires one and only one centromere in each chromosome. However, owing to their epigenetic nature, centromeres retain the potential of de novo establishment at non-centromeric chromatin. The resulting so-called neocentromere formation should be detrimental to normal chromosomes but serves beneficial to accidentally-produced acentric chromosomes in reality; it remains elusive how the 'double-edged sword' of neocentromere formation is properly controlled in the cells. Here we present evidence that the neocentromere formation is restricted by subnuclear compartmentalization and discuss its potential importance if time allows.
