CSB's Tamar Mamourian recognized for 35 years of outstanding service to U of T
Everyone in Cell & Systems Biology is familiar with the smiling face and focused tone of our Chief Administrative Officer Tamar Mamourian. She is always available to facilitate solutions to a problem, suggest more sensible alternatives, or sometimes just listen.
Tamar combines her keen perceptions with a deep understanding of the workings of the University that comes from 35 years of service. That service has been recognized by the University through the 35 Long Service Award. This Award recognizes the role she has played in the success of our institution, her commitment to excellence, and cites the benefits her efforts have yielded for her colleagues and our students.
We give our warmest congratulations to our cherished colleague, Tamar Mamourian.
In Memoriam: Professor Betty Ida Roots
The University of Toronto Community lost an eminent scholar on October 24th with the passing of Professor Betty Ida Roots, PhD, DSc, FRSC. She served the University in a number of roles; as Professor at U of T from 1969, Assistant Chair of Zoology beginning in 1972, Associate Dean of Science at UTM (then Erindale College) from 1976 and Chair of the Department of Zoology (now CSB and EEB) from 1984-1990. Roots planned, established, and directed the Electron Microscope Facility at UTM. One of her many lasting legacies is the collaborative Ph.D. program in Neuroscience at the University of Toronto, which she initiated and developed. Her friend Professor Ellie Larsen describes her as “not only a successful scientist but also a very fine leader”.
Breaking barriers: Quebec platelet disorder
A decade after the discovery that Quebec Platelet Disorder is caused by a tandem duplication, the Mitchell laboratory and collaborators demonstrate that this causes the additional copy of the duplicated PLAU gene to be on the opposite side of a CTCF genomic boundary. As a consequence, the extra copy is not insulated from the effects of a transcriptional enhancer of the adjacent VCL gene, resulting in a high level of transcription. This phenomenon is known as “enhancer hijacking”.
Read More Here
This research has been published as "Enhancer-gene rewiring in the pathogenesis of Quebec platelet disorder"
Prof Vince Tropepe's lab using zebrafish as a vertebrate model for Usher Syndrome-linked blindness
CSB Chair Vincent Tropepe has received funding from Fighting Blindness Canada to conduct research using zebrafish to study Usher syndrome, a genetic condition that results in hearing and vision loss. Loss of vision in Usher syndrome is the result of retinal degeneration, but the mechanism through which degeneration happens in unknown.
Clues to the way retinal degeneration happens in Usher syndrome can be found in the zebrafish model organism. The gene that is altered in 20% of humans with Usher syndrome is also present in zebrafish, and mutations in zebrafish that mimic the Usher-linked changes in this 'protocadherin' gene can result in reduced hearing and vision.
When the zebrafish protocadherin protein Pcdh15b is mutated in the lab, the integrity of the outer segment of retinal cells, the region that captures light, is compromised. Mutants have a progressive loss of photoreceptor outer segments, which can be attenuated by darkness or exacerbated by light exposure.
The Tropepe lab will characterize the subcellular defects that underscore photoreceptor degeneration, identify Pcdh15b-binding proteins to reveal novel Pcdh15-dependent mechanisms for photoreceptor maintenance, and catalogue the different forms of Pcdh15b to identify ones that will prevent retinal degeneration as a potential gene therapy.
We are grateful to Fighting Blindness Canada for their support; you can read more about their funded research and also donate to them here.
CSB neurobiologists identify switch that turns muscles on and off during sleep
CSB Professor John Peever, CSB PhD grad Zoltan Torontali and CSB RA Jimmy Fraigne have demonstrated a new link between arousal and muscle paralysis in mice using behavioral, electrophysiological, and chemogenetic strategies in a paper in Current Biology.
During REM sleep, muscle paralysis is induced by a region of the brain called the Sublaterodorsal Tegmental Nucleus (SLD). Involuntary muscle paralysis during wakefulness can occur in the natural phenomenon of cataplexy, whereas sleep is involuntarily induced in narcolepsy.
Prof Peever’s lab found that activation of SLD neurons in both narcoleptic and normal mice promotes cataplexy, whereas SLD silencing prevents cataplexy. This region of the brain therefore couples arousal state and motor activity during REM sleep and wakefulness.
This new understanding has the potential to treat muscular disorders in humans. In Parkinsons’s disease, the affected person’s muscles are in a continual state of rigour during wakefulness, but this rigour relaxes during REM sleep. Prof Peever dreams of helping Parkinson’s patients by applying this new understanding of the SLD to tune their muscle tension during wakefulness.
You can read more about this insight in a story from UofT News and in the Current Biology paper.
Neuroscientist Dr Jessica Pressey joins CSB in 2020 as Assistant Professor, Teaching Stream
We are fortunate to have recruited Jessica Pressey to CSB as an Assistant Professor, Teaching-Stream (3-year CLTA) as of Jan 1, 2020. Professor Pressey graduated with a PhD from Dean Woodin's lab in 2015 and completed postdoctoral research at INSERM's Institut du Fer à Moulin in Paris, France.
Her field of expertise is synaptic transmission, neuroplasticity, and brain development and as such she will be a valuable addition to CSB's Animal Physiology Major program and for CSB research project course students studying electrophysiology.
Congratulations, Professor Pressey!