Jie Liu

Dr Jie Liu obtained his PhD in Prof Tao Xu’s lab at Huazhong University of Science and Technology in China. His PhD research focused on the molecular mechanism of neurotransmitter release. In 2005, Dr. Liu joined Prof Shawn X.Z.Xu’s group at the University of Michigan studying the sensory perception, behavioural encoding neural circuits, and funcitonal ageing of the nervous system. In 2018, he was appointed as a group leader and established a sensory perception and ageing laboratory within the Department of Anatomy and Developmental Biology and the Neuroscience program at Biomedical Discovery Institute at Monash University. 

Aging not only refers to the life span but also to the physiological decline of biological organisms. Aging research in mammalian and invertebrates, due to technical limitations and organisms’ specific biological characterizations, respectively focus on organ-based pathobiology and life span regulation. Invertebrate organisms including C. elegan, however, have much to offer beyond the life span regulation data they so readily provide for us. Dr. Liu seek to bridge a vital gap in aging research by moving beyond current studies of invertebrate life span regulation drawing from his strong graduate training in single-cell functional assays. By continually evaluating motor activity over C. elegans lifespan and investigating potential effects of longevity-promoting mutants for improved motor ability, his research showed that age-related functional deterioration begins in motor neurons during early-life (Cell Metabolism, 2013). This is followed by muscular impairment during mid- to late-life. His findings challenge the previous opinion that locomotory senescence is driven by age-associated deterioration in muscles rather than in motor neurons. His research further demonstrated that both long-lived mutants in daf-2 (an insulin receptor-like gene) and arecoline (a muscarinic agonist from areca nut) treatment, promote motor activity in aging worms by postponing functional decay in motor neurons. Dr Liu hereby provide a new means of evaluating age-associated neural functions in genetic model organisms and offer a novel model for NMJs aging. 

Aging is also associated with anatomical and functional changes in the neural circuits. Exploring the underlying mechanisms of the neural circuits will significantly promote our understanding in functional ageing in the nervous system. By examining highly accessible genetic profiles and neural wiring diagrams for C. elegans, Dr Liu was able to advance our current map of the neural networks responsible for their distinctive locomotion behavior. He discovered that how different neural circuits act either solely or jointly to trigger an identical behaviour (Cell 2011), and how one neuron regulates distinctive behaviors by interacting with various neural circuits in C. elegans (Cell 2014). 

Given aging process in model organisms is strongly modulated by environmental cues, Dr Liu is also interested in sensory transduction in C. elegans. He and his colleagues found that short wavelength light stimuli elicit a negative phototaxis in eyeless worms (Nature Neuroscience 2008). Dr Liu further identified LITE-1, a putative G-protein-couple receptor, as a novel light receptor in worms, and elucidated an orchestrated G protein-dependent cGMP pathway is responsible for the phototransduction in C. elegans (Nature Neuroscience 2010).

1: Sensory perception;

2: Behavioural encoding neural circuits;

3: Functional ageing of the nervous system.