As anticipation builds for the longer days that follow this weekend’s switch to daylight savings time, the moment seemed ideal to turn to one of the nation’s leading circadian-rhythms researchers, UC Santa Cruz’s Carrie Partch.
A professor of chemistry and biochemistry, Parch has been recognized many times over for her contributions to the molecular understanding of circadian rhythms. Most recently, this summer she was named one of just 26 top U.S. scientists chosen by the Howard Hughes Medical Institute (HHMI) to be a prestigious HHMI investigator.
Professor Carrie Partch. Photo: Carolyn Lagattuta/UC Santa Cruz
Partch’s lab aims to build on a molecular understanding of biological clocks to develop innovative strategies to treat a broad spectrum of human diseases, including psychiatric disorders, diabetes, cardiovascular disease, and cancer. Her team strives to understand the molecular basis of circadian timekeeping by studying the structure, dynamics, and interactions of dedicated clock proteins.
With Partch’s deep expertise on how our natural rhythms work and can be disrupted, we asked her some of the most basic question about what we can do in our daily lives to regulate our biological clocks, what discoveries have been made that could improve our health and well-being, and the importance of funding research in this area to ensure such breakthroughs continue to be made.
How important is it to a person's health to have well-regulated circadian rhythms, and what's at stake if they aren't?
Although circadian clocks “tick” inside each of your cells, they are coordinated by a master clock in the brain that responds directly to environmental cues like light. Circadian rhythms create natural daily timing cues in your body that help you focus and be alert during the day and sleep at night—and that is intricately tied to your health. Circadian rhythms control everything from when your metabolism is most active each day to how your wounds heal and how you respond to immune challenges like viruses.
These bodily rhythms work together to enhance your wellbeing and make you healthiest when your activity lines up with Earth’s day. Working at night in shift work or having prolonged jet lag can disrupt circadian rhythms and increase your risk for obesity, cardiovascular disease and cancer.
How much can regulation be optimized by focusing on processes at the molecular level, versus everyday actions such going to bed at consistent time, exercising regularly, or meditating?
Establishing routines like exercising during the day, not eating too late, and having a screen-free wind-down time at night all promote healthy circadian rhythms. Most of us have heard that bright light at night isn’t good for sleep; this is because it tells our clocks that it’s still daytime and it holds off hormones like melatonin that help us prepare to sleep. But you may not know that getting a good dose of sunlight in the morning—at least 30 minutes—is just as important because it helps to synchronize clocks throughout your body and set up your circadian rhythms to work best, enabling a good night of sleep at the end of the day.
Those of us who are "clock watchers," or chronobiologists, are beginning to focus on strategies to harness the power of circadian rhythms to make people feel better. For example, there is good evidence that limiting caloric intake to a window of around 10 hours during the day can lead to weight loss, improve metabolic markers, and even lower blood pressure in people. Other researchers, like Professor Jake Chen at the University of Texas Health Science Center, have discovered natural products like nobiletin (derived from citrus fruits) that enhance circadian rhythms, fighting off the effects of a high fat “Western diet,” and even improving activity and cognitive function in aged mice.
Given that most people's biological compositions are unique, are there common molecular targets that you've found to address health issues like sleep or metabolic disorders? You and colleagues recently discovered a secret to regulating our biological clocks that offers a new approach to ending jet lag.
Every person’s circadian clocks tick at a slightly different rate around 24 hours or so —circadian actually means "about a day"—so our exposure to light is crucial to line up our activity with the exact 24-hour day. But some folks inherit circadian clocks that run hours shorter or longer than a day, affecting their sleep cycles and making them extreme early risers or night owls. We’ve been able to take these inherited changes to the sequences of clock genes and learn about steps in the molecular clock that are particularly important for making a clock close to 24 hours. We hope that insights like these will help us learn how to minimize the effects of jet lag and shift work.
You've also recently been named a Howard Hughes Medical Institute Investigator based on your leading contributions to the molecular understanding of circadian rhythms. What are the biggest questions you hope to address with the significant resources that come with this honor?
We’re actually still trying to understand exactly how these biological clocks work in our cells and in a diverse array of species from insects to fungi and even bacteria. We want to understand how these protein “cogs” work together, so we take them apart and solve their structures to learn how changes in their shape and atomic make-up allow them to measure time throughout the day. Support from HHMI has allowed us to take on some exciting but challenging projects, including translating some of our knowledge of clock protein function into drug discovery.
Given how long it takes for fundamental scientific discoveries to be applied in the creation of pharmaceuticals and other products that benefit people's lives, how should we see the importance of basic research in the overall effort to improve how we treat and cure humanity's most serious disorders—especially at a time when the future of federal funding feels so fraught?
Basic biomedical research is the fundamental exploration of life and how the human body works—and there are still so many unanswered questions out there! Some of the most innovative recent advances in healthcare, like cancer immunotherapies or gene-therapy cures for sickle cell patients, were built upon insights learned while researching the most basic scientific questions. Federal funding has been the backbone of scientific research in this country, allowing the U.S. to lead the world in discovery and innovation. Continued investment in basic science research and training the next generation of scientists who dig into life’s mysteries will lead to treatments or cures for diseases that we can’t even comprehend now.
