Electrochemical research? Waterloo snailed it

by Victoria Van Cappellen, Science Communications.

Biologists have discovered how an outer shield over T-type channels change the electrochemical signaling of heart and brain cells.  Understanding how these shields work will help researchers eventually develop a new class of drugs for treating epilepsy, cardiovascular disease and cancer.

The study from the University of Waterloo was published in the Journal of Biological Chemistry and was selected as the “Paper of the Week” for its significance.

Biology graduate students Adriano Senatore, Wendy Guan and Research Associate Adrienne Boone carried out the research under the supervision of Professor David Spafford.

The researchers discovered T-type channels in the pond snail, Lymnaea stagnalis, can shift from using calcium ions to using sodium ions to generate the electrical signal because of an outer shield of amino acids called a turret situated above the channel’s entrance.

Low voltage T-type channels generate tiny pulses of current at regular intervals by selectively passing positively charged cations across the cell’s membrane through a gate-like channel. The channels are normally extremely selective, allowing only one sodium ion to pass for every 10,000 calcium ions.

The resulting rhythmic signals produced by this transfer of cations are what support the synchronous contraction of our heart muscles and neuronal firing in parts of the brain, like the thalamus, which helps regulate our sleep-wake cycle, or circadian rhythm.

In addition to their published findings, the researchers also found the shield-like turrets in pond snails restrict access of therapeutic drugs to the channel.

T-type channels in pond snails and other invertebrates are similar to those found in humans. Although pond snails reach only 7 cm in length, its simple neural network and physiology make it a popular model organism with neurobiologists.

Over-active T-type channels have been linked to epilepsy, cardiac problems, neuropathic pain, as well as the spreading of several kinds of cancer have been linked to. Drugs that could quench out-of-control T-type channel activity are unable to bind to the channels themselves.

We wanted to understand the molecular structures of T-type channels,” said Spafford. “How they pass ionic currents to generate electrical activity, and to identify drug binding sites, and the drugs which may block these channels to treat neurological disease or heart complications.”

The group is currently investigating how dismantling this turret will improve drug access and binding in T-type channels.

Adriano Senatore recently graduated with his doctorate in 2013. He received the Governor General’s Medal for best PhD thesis at the University of Waterloo. Senatore has published more than a dozen research articles with Prof. Spafford for his PhD thesis research.

This work was funded by the Heart and Stroke Foundation of Canada and the NSERC Discovery program.

 

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UWAG presents more MFA theses

The University of Waterloo Art Gallery (UWAG) is displaying exhibitions by two Master of Fine Arts (MFA) candidates from May 1 to 17.

In Gallery 1 is Srdjan Segan's Something is Missing, which is described as "a sculptural installation that is rooted in notions of failure and empathy. It is a failing affect machine. In the installation, drawings of organs are desperate to inhabit imaginary bodies. Security cameras that resemble the examining tools of a medical practitioner fail to fix or function. The walls fall short of making up a room; the room becomes a metaphor for an empty stage without actors."

Segan is completing the MFA program at the University of Waterloo and received his undergraduate degree from Ontario College of Art and Design in 2004. Since then, he has been exhibiting nationally and internationally.

In Gallery Two is Ian McMurrich's "should one react against the laziness of railway tracks between the passage of two trains," which investigates the everyday as experienced in the post-industrial landscape. McMurrich conducted fieldwork during treks that followed the route of the railway in the Kitchener-Waterloo area, examining detritus (of which I'm sure there was no shortage) "as readymade artifacts of the industrial economy that has abandoned the area."

"My minimal gestures and interventions engage the inherent narrative of these discarded materials," McMurrich states. "Improvised sculptures mark my route as a form of wayfinding that re-appropriates these neglected urban spaces."

Online maps document these treks as "open works of art" that can be completed by participants as self-guided tours.

McMurrich is a multidisciplinary artist who received his BFA with distinction from OCAD University in 2006. He is the recipient of several awards including a Best Portrait Photography Award from the Toronto Outdoor Art Exhibition and a Governor General’s Academic Medal.

The exhibition, which is free and open to the public, kicks off with an opening reception on Thursday, May 1 from 5:00 p.m. to 8:00 p.m.

 

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TEDxUW videos online and other notes

The videos of the talks presented at TEDxUW, held March 15, are now online for your viral viewing pleasure. Speakers include David Wilkin, Christina Marchand, Mike Kirkup, Rod Regier, Paul Salvini, Frank Gu, Ginny Dybenko, and Josh Neufeld.

Human Resources is reporting that retiree Maria Forthuber died April 3. She began working at the University in September 1982 and was a housekeeper in Village One until her retirement in December 1989. She was predeceased by her spouse Hans in 1978. She was 89.

Finally, the fire drills scheduled for today are cancelled due to the weather. They will be rescheduled at a later date.

 

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