Reading the chemical cues

Left: Logan Donaldson

From their environment and from within, cells in the human body are constantly receiving chemical cues that are acted upon by signalling proteins. York biology Professor Logan Donaldson is investigating ways in which cancer is caused by damaged signalling proteins.

A cell’s decision to mature or divide is made by a class of signalling proteins that work together to receive, process and collate chemical cues, explains Donaldson. However, just as a malfunctioning traffic light can create havoc at an intersection, a malfunctioning signalling protein can cause a cell to lose its ability to grow properly. If the damage occurs at a particularly important signalling junction, the end result may be cancer.

“We can’t just get rid of these oncoproteins, as they’re called, because we need them to live,” says Donaldson. The Donaldson laboratory in the University’s Farquharson Life Sciences Building uses a technique called nuclear magnetic resonance (NMR) spectroscopy to determine the structure of oncoproteins at the highest (atomic) level of detail possible.

With this information, the Donaldson laboratory can determine what type of changes make a “good protein turn bad”. The laboratory also relies on biochemistry and computer modelling to complete the molecular portrait.

Right: Image of a ‘cellular janitor’

“The ultimate goal of this research is to design medicines that are not only very potent, but also very selective,” says Donaldson.

Recently, in the Journal of Biological Chemistry, the Donaldson laboratory published the atomic level structure of ClpX, a kind of cellular janitor whose job is to remove damaged proteins and help maintain the cell. Donaldson’s constantly evolving work incorporates elements of biology, chemistry, physics and computer science, reflecting York’s commitment to innovative, relevant research that crosses traditional boundaries.

The above article was submitted to YFile by Jason Guriel, York’s Natural Sciences and Engineering Research Council of Canada SPARK student (Students Promoting Awareness of Research Knowledge). Guriel, a second-year graduate student in English, will be writing stories on York NSERC-funded researchers throughout the academic year.

SPARK is a program that was launched in 1999 at 10 universities across Canada. Through the program, students with an aptitude for communications are recruited, trained and paid to write stories based on the NSERC-supported research at participating universities. Information on the NSERC Spark Student program is available at