“In Dr. Haas’ lab, we identified the involvement of the transcription factor MEF2 in regulating metaplasticity by accident. The finding was totally unexpected,” says Dr. Simon Chen, who completed his PhD in Dr. Kurt Haas’ lab at UBC. Dr. Chen is currently finishing up his postdoctoral work at the University of California, San Diego, before heading to the University of Ottawa where he will take up a Canada Research Chair in Neural Circuits and Behavior.
“The fun part of science,” Chen says, “is that you never know what you will find.”
“Simon was an incredible asset to the lab,” says Dr. Haas. “He was able to produce a very high caliber of work, culminating in first-author citations on papers in Cell and Neuron. We’re tremendously proud of what he accomplished here, and of his tenure-track appointment in Ottawa.”
Dr. Chen began his research career as an undergraduate volunteer in Dr. Haas’ lab in 2005.
“I didn’t know much about research when I started,” Chen says. “Kurt taught me everything I know!”
In the Haas Lab, Dr. Chen explored how synapse formation and neuronal activity direct the plasticity of neural networks in the developing brain. In addition to his education in cellular and molecular neurobiology, he was influenced by Dr. Tim Murphy and Dr. Catharine Rankin; he credits both professors with inspiring his post-doctoral work in two-photon imaging during learning.
At the University of California, San Diego, in Dr. Takaki Komiyama’s lab, Chen pursued two-photon imaging in order to better understand the cell type-specific plasticity that informs the way the brain learns skilled movements. In their Nature and Nature Neuroscience papers in 2014 and 2015, respectively, Chen and colleagues described their discovery that motor learning refines activity patterns among populations of cortical neurons, leading to the development of a novel code of spatiotemporal activity that potentially underlies the newly acquired motor skill.
In addition, they demonstrated the inhibition from a specific subtype of inhibitory neurons is important in the acquisition of newly learned motor skill – discoveries that have potential implications for the development of therapeutic strategies for counteracting neural circuit dysfunction associated with stroke, traumatic brain injury, and Parkinson disease.
“I want to keep doing in vivo two-photon imaging so I can see how brain changes during learning,” says Chen. “I want to more completely understand how it creates and stores memories at the molecular, cellular and circuit level.”
His new lab at the University of Ottawa will help him do just that – his goal is to identify and visualize the neural “ensembles” that encode the formation of memories, track down where in the brain memories are stored, and to see how they are retrieved.
“I think we can eventually achieve this by combining a number of cutting-edge methodologies, including advanced imaging technologies, such as endoscope or deep brain two-photon imaging, opto- and chemo- genetics, and different transgenic mouse lines combined with new generation pseudotype rabies virus to label and identify neurons that are involved in a given memory,” says Chen.
As he moves forward to this next stage of his career, he looks forward to maintaining a connection with the Centre through ongoing mentorship from Dr. Haas and Dr. Shernaz Bamji and hopes to establish new collaborations with other researchers at the Centre.
“I really value my connection with Kurt and Shernaz,” Chen says. “Science is collaborative – I still ask for help from my lab mates all the time! Everyone’s got different strengths, and it’s how you find opportunities to optimize those strengths that leads to the greatest discoveries.”