DNA structure could hold key to our memory

A specific type of DNA structure could hold the key to regulating our memory, a new study from The Australian National University (ANU) has shown.  

G-quadruplex DNA (G4-DNA) is generally found in cells when certain kinds of DNA sequences fold into a different, four-stranded structure.  

G4-DNA is usually associated with DNA damage and frequently observed in cancer cells.  

But lead author of the study, Dr Paul Marshall from ANU, said G4-DNA has now also been shown to play a role in transcribing memories. 

“For decades, many scientists have considered the topic of DNA structure to be solved. But that’s not the while story,” Dr Marshall said.  

“It doesn’t just exist as the familiar double-helix – it can assume a variety of states. 

“DNA is constantly changing and rather than being a liability, this is a key feature of our biological system and its adaptability.” 

Dr Marshall said while there is “abundant” evidence demonstrating G4-DNA’s involvement in stalling some of our cells most basic functions — replication and transcription — this is the first evidence of its role in making memories in an “in vivo” study, done on living cells or organisms.  

“We found that casually manipulating G4-DNA can lead to a substantial impairment in memory,” Dr Marshall said. 

“But in other scenarios it can result in increased transcription. It can have different effects on memory depending on the area of the brain, and type of memory involved. 

“The dynamic accumulation of G4-DNA has multiple functions in the brain’s neurons, and is regulated by a specific helicase, or enzyme. 

“This study adds to our understanding of how we encode information and experiences.” 

The research team also included scientists from The University of Queensland, Linköping University in Sweden, the Weizmann Institute of Science in Israel, and the University of California. 

The study has been published in the Journal of Neuroscience.