Misty Riddle, an assistant professor in the Department of Biology, was awarded over $1.3 million from a National Science Foundation CAREER Award to study host-microbiome interactions.
Within the last award cycle, six NSF CAREER Awards have been awarded to University faculty, which is a 46% success rate of applications submitted. According to the NSF website, CAREER Awards support early-career faculty who have the potential to serve as academic role models in research and education.
Riddle’s CAREER Award, titled “Leveraging natural diversity to uncover the genetic basis of host-microbiome interactions,” will use the Mexican tetra, a small species of fish, which Riddle has studied to understand morphological and physiological evolution. Her goal is to use the fish as a model to understand how genetics shape the community of microbes living in the digestive tract.
The number of studies on microbiomes has skyrocketed in the past decade as researchers have learned how much the microbiome impacts the health of its host. Below, Riddle shares how she plans to use genetic techniques to study the microbiome of these unique fish.
Please describe the research your CAREER Award will support.
We will investigate how host genetics shape the community of microbes that live in the digestive tract and influence health, metabolism, and immunity. To do this, we use the Mexican tetra (Astyanax mexicanus), a species of freshwater fish that includes both surface-dwelling and eyeless cave-dwelling populations. These populations differ dramatically in their metabolism and microbiome composition, even when raised in identical lab environments. By comparing these populations and their hybrids, we aim to identify the specific genetic variants that determine which microbes thrive in the gut and how these microbes, in turn, impact the metabolism of the host.
What are the real-world implications of this research? What do you hope to achieve?
Imbalances in the gut microbiome are linked to human health conditions such as obesity and diabetes, but we still don’t understand why people differ so much in their microbiome composition. This research will uncover how natural genetic variation influences the gut microbiome, providing critical insights into which host pathways might be targeted when designing personalized microbiome-based therapies. Ultimately, this work may help us predict or improve the success of microbial interventions like probiotics based on an individual’s genetic background.
What spurred your interest in this research area? How has your interest evolved?
As an undergraduate, I studied the microbes associated with brine shrimp in the Great Salt Lake, which sparked a deep interest in host-microbiota interactions. My graduate and postdoctoral work focused on gut development and metabolic evolution, and I eventually returned to microbiome research with a new set of tools and perspectives. Now, I’m excited to combine evolutionary biology, genetics and genomics to answer longstanding questions about how host-microbe relationships evolve.
How are you planning to integrate education and outreach into your CAREER project?
This award allows me to enhance education and broaden participation in science in Nevada. I will develop a new course module for Molecular Biosciences graduate students at the University that teaches key techniques in modern genomics. I will recruit undergraduates into a structured mentorship program that offers paid research experiences in my lab. For younger students, I’m partnering with the University’s Museum of Natural History to develop a lab activity for elementary school groups that utilizes the Mexican tetra. We will also develop an exhibit for the Museum’s “Snake Saturdays” that highlights how animals, including the Mexican tetra, adapt to extreme environments. We hope to bring science to life for our community.
How do you hope to have an impact on your students' lives and futures?
I want my students to feel confident that they belong in science and can contribute to it in meaningful ways. By giving students ownership over their research projects and integrating mentorship at every stage, I aim to build their technical skills, scientific curiosity, and confidence. Whether they continue in academia, go into industry, or pursue other paths, I hope they carry with them a passion for discovery and the ability to think critically about the natural world.
What's next for you, your research, and your career?
This CAREER award sets the stage for expanding my lab’s research in exciting new directions. We’re eager to use gene editing tools to test the function of specific genetic variants that influence microbiome composition and host metabolism. Looking ahead, I plan to develop gut organoids from the Mexican tetra to study gut homeostasis and host-microbiome interactions in system that is easy to visualize and manipulate. As the project evolves, I aim to strengthen collaborations with scientists in microbiology, genomics and physiology to broaden the scope and impact of our work. These efforts will help establish new experimental platforms and drive discovery at the intersection of genetics, evolution, and host-microbiome interactions.
