Research led by Prof. Jacque P.K. Ip, Assistant Professor of the School of Biomedical Sciences (SBS) has made a breakthrough in understanding how circular ribonucleic acid (circular RNA) molecules contribute to the brain’s ability to form memories. The findings, published in the international journal Science Advances, open new possibilities for future treatment of neurodegenerative diseases, including Alzheimer’s disease and amyotrophic lateral sclerosis (ALS).

Researchers identified circHomer1, a brain-enriched circular RNA derived from the Homer1 gene, as an essential regulator of synaptic function. They used the Barnes maze test to assess the spatial learning and memory performance of mice with reduced circHomer1, comparing them with control mice. Results showed that mice lacking circHomer1 took significantly longer to find the target hole and made more errors in locating it during the probe trial, compared to the controls.

Prof. Ip said: “These behavioural impairments across multiple cognitive tasks indicate that circHomer1 is required for hippocampus-dependent spatial learning and memory.”

The team further revealed that circHomer1 acts as a molecular bridge that enables the transport of essential synaptic mRNAs to the dendrites of neurons. Losing circHomer1 weakens brain communication by deforming the dendritic spines, the “sockets” of synapses, and reducing the quantities of essential proteins they need to function.

“This study opens a completely new direction for the diagnosis and investigation of neurodegenerative disorders. Circulating circular RNAs could serve as biomarkers for neurological conditions. Additionally, restoring circHomer1 function could offer a distinct strategy for maintaining synaptic health and memory, even in the presence of other neuropathologies.” Prof. Ip explained.

The related coverage by the Communications and Public Relations Office and the Faculty of Medicine, CUHK can be viewed HERE and HERE respectively.