Tetsuya Hisanaga

Current projects:

Project 1: Chromatin dynamics during sexual reproduction 

During sperm development in bryophytes, histone-based nucleosomes are replaced by sperm-specific nuclear basic proteins such as protamine. This means that chromatin landscapes encoded by histone post-translational modifications (PTMs) are erased during spermatogenesis and must be re-established after fertilization. I would like to understand mechanisms regulating this dynamic change in chromatin landscape during sexual reproduction using a model bryophyte, Marchantia polymorpha.


Project 2: Role of PRC2 in transposon silencing

Transposable elements (TEs) are mobile DNA fragments that can jump within a genome. Expression of TEs is usually silenced since TE expression and jumping could lead to genomic instability. In mammals and flowering plants, most TEs are packed and silenced by constitutive heterochromatin which is covered by H3K9me2/3 marks. Contrary to this, in Marchantia, we discovered that some TEs are covered by H3K27me3 deposited by PRC2 complex. I would like to address the question of whether these TE-associated H3K27me3 marks have a role in TE silencing.