Of Histones and Humans

Professor Iva Zovkic
Monday, July 6, 2015 - 9:44am
Carla DeMarco
Professor Iva Zovkic in U of T Mississauga’s Department of Psychology focuses on epigenetics for her neuroscience research in learning and memory

Professor Iva Zovkic started out studying drug addiction in adolescent rodents, but a couple of conferences during her graduate work hooked her onto epigenetics and their effects on learning, memory and behaviour, and she has been fixated by its potential ever since.

“When I heard the presentations on epigenetics I decided then and there that that’s what I wanted to do, firstly because it’s absolutely amazing, and secondly this changed the way we all think about learning and memory,” says Zovkic. “I love the idea of being able to study how epigenetic changes happen instantly, but also how they can last for a long time.”

Firstly a talk in 2008 given by a postdoc working with Michael Meaney at McGill demonstrated that variations in maternal care in early life cause long-lasting alterations in certain types of behaviour, and it’s all down to epigenetics. Zovkic was intrigued and immediately recognized the relevance of this work to her adolescent-mice research.

It was a second conference talk given the following year by a post doc from Professor David Sweatt’s lab from the Department of Neurobiology at the University of Alabama Birmingham (UAB) that ultimately sealed her fate in terms of research and where she would pursue a postdoctoral appointment.

Zovkic decided to switch paths to focus on epigenetics and on memory research in particular because it’s applicable to all humans unlike drug-addiction research, which can be somewhat limiting, and she took her newly awarded NSERC Postdoctoral Fellowship and went to UAB in 2011 to be a part of the innovative Sweatt Lab.

Zovkic’s current work at UTM focuses on gene regulation in the brain and histone variant exchange in memory formation. Histones are proteins inside the nucleus that package DNA, and their modifications are involved in turning memory-related genes on and off in response to learning. These epigenetic modifications of histones and DNA can produce stable changes in gene activity without actually changing the sequence of the gene. In the case of Zovkic’s work, she used a virus to knock down levels of a particular histone-variant, H2A.Z, in the brain.

This led to an important discovery: that H2A.Z, which is typically studied in relation to development and cancer, is also involved in regulating cognitive function. This has several related consequences for this field, including that it could be used to treat memory-related disorders in the future.

Overall Zovkic sees huge potential for epigenetics and for histone variants in particular, however there is still much to be discovered about their relationship to memory. Additionally, histone variants are found across species so there are profound implications of this research for a variety of disciplines, not just neuroscience, with applications in a number of areas such as aging, disease, and mental health.

For her own cognition improvement, and to get a break from the lab sometimes, Zovkic has found her own perfect pursuit recently in the form of eGames, particularly with the five-on-five game called Defense of the Ancients (DotA) that requires you to defend your own zone while trying to attack your opponent’s zone.

“I’ve learned that gaming helps to make you smart, plus it’s so much fun!” enthuses Zovkic. “You are engaging your brain in a way that you never use it during the day, and playing challenges you in a completely different way.”

Warcraft and gaming aside, Zovkic sounds pretty challenged and focused with her work and her various endeavours. Her lab is bustling having recently been awarded two NSERC grants, and she has lots of ideas for new experiments that she eventually wants to try but will have to wait pending further funding since her research can be quite costly.

She is also married to an academic who is a postdoc in Sheena Josselyn’s lab at Sick Kids, and they have collaborated on work, with two papers they co-wrote just being published.

Zovkic says she is grateful to have that partnership because since her husband’s work is related to hers she often bounces ideas off him or has him read her draft proposals. He will point to the gaps in her work, and is at times “brutally” honest, but she feels ultimately it makes her grant proposals stronger and makes her aware of the blind spots or of overlooking the obvious.

And does she reciprocate the favour?

“Oh yes, I do,” she says with a laugh. “He will ask me why everything he sends me comes back completely red, and I tell him that’s what I am here for. But I love it. It absolutely makes science more fun.”