Folded Genomes May Hold Clues to Cephalopod Brain Evolution
Scientists at the University of Vienna examined the three-dimensional folding of genomes in octopuses, squid, and cuttlefish. They found that ancient, large-scale genome rearrangements brought distant DNA regions into contact, altering gene regulation. This 'regulatory entanglement' may help explain how coleoid cephalopods evolved large, complex nervous systems and sophisticated behaviors.
Researchers compared how DNA is folded inside cells across octopuses, squid, and cuttlefish. Hundreds of millions of years ago, major rearrangements shuffled these genomes, placing once-separated chromosome regions near one another. Such proximity allowed new regulatory interactions to form and persist, a phenomenon the team calls regulatory entanglement.
The study also distinguished stable chromatin domains from more variable chromatin loops. Loops differed by species, tissue, and developmental stage, and often sat near genes tied to cephalopod features, including nervous system traits. The work appears in Nature Communications and was led by Dr. Thea Rogers at the University of Vienna.
This finding may interest neurobiologists, evolutionary biologists, and science educators, as it offers a new lens on how complex nervous systems and behaviors could arise. It might also shape public understanding of evolution by emphasizing genome folding, not just gene sequences. Any medical, biotechnological, or computational applications remain speculative and distant, so near-term effects are likely confined to research and education.