Andrew C Liu, PhD

I am a Professor in the Department of Physiology and Aging, College of Medicine. I earned my Ph.D. in Biochemistry from the University of Michigan Medical Center, focusing on ER stress signaling and the unfolded protein response. I completed postdoctoral training in Molecular Genetics and Genomics at The Scripps Research Institute. Since 2003, I have researched the molecular, cellular, and physiological mechanisms of mammalian circadian clocks—first as a postdoc (2003-2006), then as an institute fellow and group manager (2006-2008), and as a principal investigator (2008-present). I joined the University of Florida in 2018 where I conduct research and also participate in teaching. I have previously served as an Assistant and Associate Professor in the Department of Biological Sciences at the University of Memphis (2008-2017).

The major focus of our research program is the molecular, cellular and physiological mechanisms of circadian rhythms in mammals. We ask i) How is the molecular clockwork built in a cell (cell-autonomous) and in the central SCN (neural network)? And ii) How are the clocks integrated with metabolism and physiology, both under normal and pathological conditions (genetic network)? We use mice and cultured mammalian cells as model systems and employ highly integrated approaches in our research. Virtually every single cell in our body is a clock and each cell, organ, and organism can be studied as a system, and accordingly, we study the clock at the levels of cell, tissue, organ, and organism. More than 50% of all genes cycle somewhere in the body. As opposed to traditional methods, we use kinetic (not just steady-state snapshots) and longitudinal methods (multiple days/cycles) to measure the temporal dynamics of molecular, cellular and physiological processes.

I obtained my Ph.D. in Biochemistry at the University of Michigan and was trained in Molecular Genetics and Genomics as a postdoc at the Scripps Research Institute. Since 2003, I’ve been studying the mammalian circadian clocks, first as a postdoc (2003-2006), then as an institute fellow and group manager (2006-2008), and as a principal investigator (2008-present). In 2007, we demonstrated that intercellular coupling in the SCN (the body’s central clock) confers system robustness against genetic perturbations; peripheral clocks (e.g., fibroblasts, liver, lung), however, generally lack strong coupling and reflect gene/protein function on a biochemical and oscillator basis. Thus, the SCN is a more robust clock system and peripheral clocks are experimentally more tractable. Strategically, we use peripheral and cellular models for gene discovery and use cells and mice to study gene functions. We use multi-integrated approaches which include molecular biology, biochemistry, structural biology, genetics, functional genomics, gene discovery, and small molecule discovery.

Leveraging our expertise and cell and animal models, my lab carries out the following main areas of research: i) To probe the biochemical and structural basis of cellular circadian behavior, and neural network basis of the central SCN clock; ii) To identify novel clock genes and characterize how these genes and networks modulate clock function; iii) To investigate the extensive, bidirectional integration between the circadian clock and cell physiology, particularly nutrient/energy sensing, and innate immunity and inflammation; iv) To explore pharmacological and chronotherapeutic approaches in hopes to enhance circadian physiology and sleep/wake homeostasis and improve health.

Scientifically, our goal is to fill in the huge knowledge gap in our understanding of the molecular and cellular processes connecting genes to phenotypes and to elucidate how the molecular clocks regulate behavior, physiology, and metabolism. Ultimately, we hope to gather sufficiently detailed knowledge to effectively modulate our timekeeping system. We hope to contribute to chronotherapy and chronotherapeutics to improve treatments for circadian rhythms and sleep/wake disorders, as well as clock-related disorders.