A team of researchers from the University of Alberta’s Augustana Campus, including undergraduate students, have made a startling discovery about mitochondria, cellular structures that produce the energy that every complex life form on Earth needs to survive.
The story began on the Camrose-based campus, but ended up stretching across the country to Dalhousie University in Nova Scotia, and two billion years back in time. Under the guidance of Joel Dacks in the U of A’s Department of Cell Biology, Jeremy Wideman (BSc Biology ’05, UAlberta PhD ’12) led undergraduate researchers to discover a bacterial link with mitochondria. When researchers from Dalhousie realized that both teams were at the same stage of an identical project, they joined forces. The results were published online recently in Current Biology.
The paper shows that the delicate cristae within mitochondria were not innovations of complex cells, but were instead present in ancestral bacteria since current descendants of those bacteria also have crista-like structures that are used for similar purposes.
“Once upon a time, about two billion years ago, these tiny, quasi-independent living beings that exist in our cells lived independently as bacteria,” explained Wideman. “They took up residence inside the ancestor of our cells, began producing energy, and eventually evolved into mitochondria.
“This is the biggest paper—by far—of my career,” said Wideman, recipient of the 2014 Augustana Sessional Teaching Award. “It’s also a big deal for Augustana and for undergraduate researchers: the two students who helped with research during their degrees are co-authors.”
Undergraduate research contributes to publication
Kaitlyn Baier of Camrose and Katelyn Spencer (BSc Biology ’14) of Lethbridge were Wideman’s students when he invited each of them to take part in his research. “Baier was in my Biology 110 course, and was enthralled by evolution,” Wideman recalled. “I wanted to get her involved with research as well. She found that research can be frustrating, but that’s part of the authentic scientific experience. If you don’t get frustrated at some point, you’re probably doing science wrong.” Baier delivered a talk about her research at the Student Academic Conference in December 2013.
Spencer was recruited from Wideman’s Biology 411 course on the history and theory of biology. She worked through the rest of the data and presented her results at the April 2014 Student Academic Conference. “The idea of doing research myself was incredibly appealing,” she said. “There is only so much a book can teach. Being able to learn the skills required to do research was invaluable.”
The students were responsible for determining the evolutionary history of protein structures in cellular mitochondria. While they searched for related sequences in all eukaryotic groups (life forms including everything from single-celled organisms to plants and animals), Wideman noticed that the protein structure was correlating to bacterial proteins.
“They stared at massive amounts of bioinformatics data,” said Wideman. “Accessing a computing cluster maintained by the Dacks lab in the U of A Faculty of Medicine & Dentistry, they used sophisticated homology searching algorithms to find sequences in diverse eukaryotic genomes related to sequences present in human and fungal genomes. They assessed whether or not the proteins were similar based on standardized guidelines. A solid understanding of cell biology, cellular diversity and evolution was required.”
“Until I had a handle on the programs and the goal of the project, it was difficult,” admitted Spencer. “But once I understood what each program did, it wasn’t that hard anymore—just a lot of work.”
Wideman was delighted to work with Baier and Spencer. “I was very excited to discuss my work, to get excited with someone, to have someone help with some of the grunt work. Both students were very interested in the project, and in biology as a whole. To do this kind of research, you need in-depth knowledge about biology but also a broad understanding that you can really develop in a place like Augustana. This is a place where undergraduate students can work on major publication!”
By the end of the 2014 school year, Wideman had collected nearly all of the preliminary data. “By then we could see the conclusions,” he said, “but there was still so much work to be done. Unfortunately, undergraduate students move on after their courses are finished, so it was up to me to refine the data and get it ready for publication.” He put his results together for a poster presentation to take to Protist 2014, the International Society of Protistologists conference in Banff, only two weeks before leaving for another postdoctoral fellowship in England.
Making a cross-country connection
While presenting his findings at the conference, he was approached by a team of researchers from Dalhousie University’s Department of Biochemistry and Molecular Biology. Sergio Muñoz-Gomez and his adviser Claudio Slamovits revealed that they were working on almost exactly the same project—and were at nearly the same stage of completion.
“My initial reaction was one of fear,” said Muñoz-Gomez. “I had just been scooped! I talked to my supervisor and other professors at Dalhousie to know what the best way to proceed would be. Then I went and talked to Jeremy.”
“We did what any pure-hearted protistologist would do,” Wideman chuckled. “We joined forces and produced a single excellent paper instead of two—likely lesser—papers, which would have been competing for publication in the same journals.”
“It was great, because each one of us had initially approached the project from different perspectives,” Muñoz-Gomez recalled. “I was more focused on the origins of mitochondrial structure, whereas he was emphasizing the later diversification of mitochondrial structure during the evolution of complex cells.”
Though separated by a distance of nearly 5,000 kilometres, the two researchers worked together relentlessly. The result was a single, well-rounded paper that links mitochondria to previously existing bacteria. The paper lists Dr. Muñoz first, Dr. Wideman last, and the undergraduate students in the middle with the two advisors.
“I really appreciate the freedom that Joel Dacks gave me as my supervisor,” said Wideman, who has published six prior papers. “He gave me the freedom to be able to explore the question. And Augustana gave me the freedom to start the project with undergraduate researchers.”
“Undergraduate research is an awesome opportunity, and I’m glad I did it,” said Spencer. “It was a big highlight of my final year. Any student who gets a chance to do real undergraduate research should take it; the skills acquired are not taught in a classroom.”
Wideman is currently investigating ancient cell evolution under a European Molecular Biology Organization Long-Term Postdoctoral Fellowship in the Department of Biosciences at the University of Exeter. He is awaiting publication on another paper with an undergraduate Augustana student and collaborating on several others with groups across Europe and North America.
Related link: Globe and Mail “Canadian study reveals hidden link between cells and bacteria”. http://www.theglobeandmail.com/technology/science/canadian-study-reveals-hidden-link-between-cells-and-bacteria/article24542299/