Hossein Davarinejad is a Graduate Student in Dr. Jean-François Couture's laboratory at the University of Ottawa. Learn more about Hossein and his research in this Q&A, and check out his presentation at the April 2021 CEEHRC seminar!
What are you working on?
I joined the Couture lab in 2018 with interest in using X-ray crystallography to solve the structures of enzymes linked to epigenetic signaling. Many reasons motivated my choice to pick ATXR6. First, my lab was the first to demonstrate, structurally and biochemically, that ATXR6 mono-methylates lysine 27 on H3.1 (Bergamin E., et al 2015; Science). Second, in a subsequent paper published in Nucleic Acid Research, the lab demonstrated that the enzyme's PHD domain not only binds the nucleosome but contributes to cofactor binding. Plant studies that mutated the SET, PHD, and the uncharacterized PIP motif showed a corresponding impact on chromatin's nuclear architecture. However, little was known on why a mutant PIP motif would produce the same phenotype. After taking over this project, I showed that the evolutionary conserved PIP motif is required for binding PCNA and solved the crystal structure of the ATXR6 PIP with the DNA sliding clamp. Interestingly, we found that PCNA, which was thought of as a local carrier of such PIP-carrying enzymes, outcompetes the binding of ATXR6's canonical substrate, the nucleosome, and accordingly decreases levels of H3.1K27me1 produced by ATXR6. My work suggests that in the context of post-replication or replication-coupled re-establishment of the H3K27me1 mark, ATXR6 must be disengaged from PCNA.
Where are you from? What do you miss about your hometown/country?
I was born and raised in Iran, but home is Vancouver to me. I miss that perfect integration of a major city within a spectacular nature with so many kinds of outdoor activities being minutes away.
What city do you currently live in and what do you like most about this city?
I live in the Ottawa-Gatineau area. Neither city offers special excitement for me as far as city life goes but they have a lot more nature to offer than Toronto (where I lived for 10 year before here) and that is definitely nice about my new town.
What are some ways you detach from work/science/academia?
I try to use my charcoal grill as often as possible and throw a nice BBQ. I try to spend time with my cat and invest in cryptocurrency. I also like gardening, building, and repairing things.
Do you have any special talents outside of research that few people in your academic life know about?
I live in the IT world outside of natural sciences and I’m trying to keep my knowledge and skills updated and relevant so that they may be of use when I graduate from biochemistry.
Do you have a recommendation for a book, show, movie or documentary?
Book: 12 Rules for Life – An Antidote to Chaos, by Jordan B Peterson
TV Show: Narcos on Netflix
Movie: Heat (1995)
What made you decide to become a researcher?
My Biochemistry and Cell Biology course in 2nd year undergrad really engaged me in the field. I was fascinated to learn to what level biological sciences has explored and made solid understanding in how life works at the molecular and made links to diseases.
If you wouldn’t be a researcher, what would you like to be/think you would be?
If I could live a few hundred years I would pursue PhD level learning in architecture and interior design, physics and astronomy, music, linguistics, engineering and skills in carpentry.
What sparked your interest in epigenetics?
My start was via a research practicum course (undergrad) in a ubiquitin biology lab. Once I learnt more about my project and the literature I saw a field with so much left to decipher at such an important crossroad, the nucleosome.
If you could give your “first-year-PhD-self” one piece advice, what would it be?
I would say to myself: “you chose a fantastic lab, relax, and enjoy the ride”.
Where would you like to see your research/field of interest end up in the future?
In some sort of pharma/health sciences world with need of computing and programming.
CEEHRC Seminar Presentation