“For my postdoc, I wanted to do something in vivo, something that I could image easily and watch development occur,” says Ashley Libby, developmental biologist and the newest Molecular Genetics and Donnelly Centre faculty member. “I instantly fell in love with chickens.”
With Libby’s arrival comes a return to an older system model; an avian organism more likely to be found in a lab’s lunch fridge than found in their research. The system model of the domesticated chicken, or Gallus gallus domesticus, has fallen out of fashion in recent decades in favour of mice and other organism models in which researchers can more easily perform gene editing.
But Libby was drawn to the retro model’s reliable breeding schedule and how its embryo and organ system formation is on the timescale of hours, instead of days.
“It's a versatile, beautiful system,” Libby explains. “There's nothing like opening up an egg and seeing the embryo inside—it happens the same way every single time, which isn’t something we can say for our human stem cell differentiations. Organoids can be a wide range of shapes and cell type proportions, or even just cell types in general, whereas there's a remarkable robustness unique to the embryo, which I love.”
Libby crossed the road into working with chicken models in her postdoctoral research, following a PhD spent investigating the development of organoids—simplified organ structures grown in vitro—mimicking the formation of organs found inside the mammalian trunk (torso). Building upon this research at the Francis Crick Institute in London, Libby's postdoctoral work continued her investigation into stem cell morphogenesis, with a focus on the neural tube—the structure within a developing embryonic organism which will eventually grow into the central nervous system. To study the neural tube in depth, the Libby Lab is combining in vivo gene-editing techniques, lineage tracing, and live imaging using microscopy.
“My lab is using higher throughput methods to ask, ‘how do cells know how to build tissue,’” Libby says. “We’re taking modern techniques developed for human or mouse stem cells and tissue cultures, and we’re applying them towards chickens. It’s the best of both worlds: a relatively cheap model system that you can easily access, with all the advantages of being able to watch development in real time.”
Libby imagines a future where her lab’s research into embryonic development will be used to try to recapitulate organ development with human stem cells, making higher functioning and repeatable organs. In addition to spinal cord development, Libby hopes to eventually tackle avian eyes.
“That means we’ll use raptor species, which is what you might call hunting birds,” Libby says. “Species like hawks and eagles have a fovea, which is an indentation in your eye that helps you focus. Raptor species actually have two foveae layered on top of each other.”
As a Centre with over thirty labs studying a variety of system models, Libby considers her research to be “expanding the Donnelly zoo" through the addition of her chickens.
“On behalf of everyone at the Donnelly, I extend a warm welcome to Dr. Libby,” says Stephane Angers, Director of the Donnelly Centre. “Her interdisciplinary approach will unlock understanding of how stem and progenitor cells respond to their environment to form tissues during development. We're excited to see her use in vivo functional genomic approaches to tackle these important questions.”
Libby is ready to build her lab towards her research vision and to be a part of a larger revitalization she’s seeing with the use of chickens.
“There's an upcoming wave of younger chicken labs, now that the technology has become so advanced that we can move it into chicken—or become so commonplace that we can figure out how to get it into chicken,” says Libby. “There's this revamp of the chicken community, all while standing on the shoulders of giants. I’m excited to see it.”
This article was originally published by the Donnelly Centre and has been adapted for the Department of Molecular Genetics.
