This week’s big science news is that researchers have finally sequenced the gene for a cephalopod– the California two-spot octopus, Octopus bimaculoides. Geneticists and molecular biologists from the University of Chicago and Berkley worked together to unravel the entire gene—which turned out to be nearly as large as the human genome and did not contain any mass data duplication (which some vertebrate-centric scientists had thought might account for the size and complexity). To quote Business Insider, “The work will allow scientists to study the genetic factors that give way to the octopus’ odd physical traits, and may reveal novel insights not only about the unique biology of cephalopods, but also about the evolution of traits that give rise to a complex nervous system and adaptive camouflage.”
There are already some fascinating initial discoveries from the octopus gene sequence data. Not surprisingly, the scientists discovered completely unique genomic sequences for reflectins (which allow the octopus to change color instantly). Even more intriguingly, the researchers discovered a huge suffusion of protocadherins—which facilitate the interaction between neurons. Octopus seem to have many more of these neural development genes than expected–and indeed the eight legged sea creatures have twice as many protocadherins as more familiar mammalian creatures like humans. However the majority of the data requires additional study. Scientists also hope to contextualize the somewhat abstract genes by sequencing other cephalopods (particularly cuttlefish—which a different team is working on).
Unfortunately I am not a geneticist and the niceties of jumping genes are somewhat lost on me. I am however greatly interested in finding out more about the biology and evolutionary history of cephalopods. This class of organisms has attained a shockingly high degree of intelligence through a very different evolutionary path than the most intelligent vertebrates (like primates, proboscideans, cetaceans, and parrots). The clever mollusks are capable of solving difficult puzzles in unexpected ways and their donut shaped brains have long perplexed and intrigued neurologists. Perhaps further details of their genetic makeup will yield the seed for tomorrow’s transgenically created superbrains! Barring that, it would be good to understand the mechanisms of diverse neural systems and grasp more about the development of these beautiful yet unfamiliar creatures.