M.Biotech Teaching Faculty, Guojun Yang, Profiled

Professor Guojun Yang matches his laboratory perfectly--the impeccably neat, organized and curious researcher is clearly at home amidst the gleaming metal, sparkling test tubes and advanced electronics found in his corner of U of T Mississauga.

From the spotless counters and colourful trays, it's not obvious that Yang, an assistant professor in the Department of Biology, deals with plants and insects in his quest to understand an integral part of all genomes. Yang's research focuses on transposable elements (TEs), fragments of DNA that can jump from one genome position to another, often producing extra copies of themselves in the process.

Transposable elements are abundant-for instance, about 50 per cent of human DNA is made up of TEs. Once considered a genomic junk yard, they are often found to be a critical part of genome evolution and many biological processes. They are potent sources of mutation and are an integral, active, and both destructive and constructive component of genomes.

For example, says Yang, our immune systems fight against various germs in our environment by rearranging DNA fragments to produce many different forms of antibodies. "This rearrangement is basically a transposition event," says Yang. "Transposable elements are very powerful tools for genetic studies...Now people are testing some of the elements for use in gene therapy."

A thorough understanding of the functional roles and population dynamics of TEs will provide a better comprehension of genome evolution and function.

In a study recently published in the journal Science, and highlighted in the journal Cell, lead author Yang and the other researchers examined the relationship between a special type of TE called miniature inverted repeat transposable elements (MITEs). These results contribute to the understanding of how TEs co-evolve with their host, and the principles they discovered may apply to a broad range of organisms. 

Yang began his studies with the rice genome, and more recently, has been studying MITEs in insects such as mosquitoes using molecular genetics, bioinformatics and genomics approaches. His team aims to understand how TEs shape genome function and evolution and to develop TE based genetic tools.

Yang completed the Science study along with his former colleagues at the University of Georgia in Athens, Ga. Before his time in Georgia, Yang studied at both Texas A&M University in College Station, Texas, and at Guangxi University in Guangxi, China.

A recipient of a Connaught Start-up Fund, Yang was also awarded a Natural Sciences and Engineering Research Council of Canada Discovery Grant for 2009-14, and has reviewed articles for various journals, including the Proceedings of the National Academy of Sciences, Evolution and Genetics.