On December 24, 2025, at the invitation of Professor Tong Xiajing and Hu Ji, Professor Li Wei, Dean of the Sans Institute for Neuroscience & Vision Research at Shanghai Jiao Tong University School of Medicine, delivered an insightful lecture titled "Seeing in the cold": hibernation biology and its potential applications.
Hibernation is a survival strategy for animals to cope with harsh winters. The ground squirrel, a heterothermic mammal, can lower its body temperature to 4-10°C during hibernation and rapidly restore normal physiological functions upon arousal. Using the visual system of the ground squirrel as a model, Professor Li Wei unveiled the underlying biological mechanisms and discussed their significant potential for medical applications.
The report focused on four key research discoveries:
The "Spotlight" Function of Mitochondria. Professor Li's team discovered that the arrangement of mitochondria in retinal photoreceptors changes with hibernation. In active states, mitochondria are neatly aligned in the inner segment of photoreceptors. This ordered distribution was found to focus light, directly aiding in phototransduction—a novel function beyond energy production. During hibernation, mitochondria become disordered to conserve energy.
Reversible Changes in Ribbon Synapses. Ribbon synapses in photoreceptors hold numerous vesicles for continuous signal transmission. The research found that these ribbon synapses disappear during hibernation, reverting to standard synapses to reduce energy consumption. However, a small pool of vesicles near the release site is retained, enabling rapid visual recovery upon emergency awakening. This process is regulated by the interaction between RIBEYE and Bassoon proteins.
FOXO1 Protein and Cold Tolerance Mechanism. How do ground squirrel organs withstand prolonged cold without damage? The key lies in the transcription factor FOXO1. In ground squirrel cells, FOXO1 uniquely translocates into the nucleus under low temperatures, activating protective responses that confer cold tolerance. Leveraging this mechanism, the team developed strategies to promote FOXO1 nuclear localization, successfully enhancing cold tolerance in mouse and human cells. This breakthrough offers a revolutionary approach to extending the preservation time of organs for transplantation.
RNF114 and Reversible "Cataracts". The ground squirrel's lens becomes opaque at low temperatures (resembling a cataract) but turns transparent again upon warming. The study identified the E3 ubiquitin ligase RNF114 as the key regulator of this reversible change by controlling lens protein stability. This finding points to a potential new target for non-invasive cataract treatments.
During the Q&A session, faculty and students engaged in a lively discussion with Professor Li on various scientific questions. The lecture provided a cutting-edge perspective, demonstrating how fundamental biological research can inspire advances in fields like low-temperature medicine, neuroprotection, and organ transplantation.
[Brief Biography of Professor Li Wei]
Li Wei is currently the Dean of the Sans Institute for Neuroscience & Vision Research at Shanghai Jiao Tong University School of Medicine. He previously served as a Senior Investigator and Lab Chief at the National Eye Institute (NEI), NIH, USA. An international leader in vision science, he holds positions such as Chair of the FASEB Retinal Neurobiology Conference and Councilor/Vice-President-Elect of ARVO. His honors include the SAYER Award and ARVO Fellow.
*This article was primarily generated by DeepSeek.