QBI Professors Massimo Hilliard and Geoffrey Goodhill have received NHMRC Investigator grants to continue their research for the next five years into understanding brain function, which will shed light on brain and neurodevelopmental disorders.
Using this funding, the researchers will piece together two major puzzles—how to repair nerve cells following an injury and how neural circuits develop—knowledge that will deliver huge insights into how the brain works.
Roundworms shed light on nerve injuries
Nerve cells, or neurons, communicate with each other and with other cells by transmitting electrochemical signals via their long and thin, cable-like structures called axons. Axons bundle together forming nerves.
The extreme length of the axons, reaching one metre in some cases, makes them highly susceptible to break when injuries strike, such as those in the spinal cord causing paralysis. The limited ability of mature adult neurons to spontaneously repair their axons following damage, combined with their minute dimensions that make neurosurgery challenging, have hampered the treatment of nerve injuries.
Professor Hilliard has previously revealed that two separated fragments of an axon are able to spontaneously re-join in the microscopic roundworm Caenorhabditis elegans, and start communicating again.
“We found that the successful re-joining of the two separated axon fragments and the functional recovery in the tiny C. elegans worm was made possible by molecules spanning the cell membranes.”
“If we can use genetic tools to figure out and control the molecular mechanisms used in the repair process, we may be able to apply that to humans to help repair nerve damage.”
Neural circuits can be visualised in zebrafish
Instead of a 1 mm long worm, Professor Goodhill is studying 4 mm zebrafish larvae.
Zebrafish larvae are transparent, allowing researchers to see the electrical activity of neurons under a microscope, and thus increase our understanding of neural circuits.
“We are investigating how brains process information, particularly during development, and how the circuits in the brain develop both normally and abnormally,” Professor Goodhill said.
“We can take images of neural activity in the whole zebrafish brain at different stages of development. Applying a variety of mathematical and computational methods to these data then helps us understand how the brain develops as a computational device.”
“We are also studying how zebrafish brain development is affected by mutation of the gene FMR1, which in humans is the most common inherited cause of autism.
“Analysing the development of brain circuits in this way can help us understand more about how neurodevelopmental disorders such as autism arise, and how such disorders affect neural processing.”
