Scientists for the first time were able to unlock octopus genome sequence that would reveal how the eight-legged creature evolved. Biologists believe that his feat could help them reveal more details about gene families that might hold key to how “intelligent” animal wires up its complex brain.
The researchers sequenced the genome of California two-octopus (Octopus bimaculoides). This was the first ever celphalopod to be fully sequenced, and the genome had surprising differences from other invertebrates. The dramatic expansion of gene family, helps in the neuronal development that was thought to be unique to vertebrates.
Caroline Albertin, lead study researcher and graduate student studying evolution at the University of Chicago said that these octopus species produce gorgeous transparent eggs that hatch and start behaving immediately like an octopus.
Study co-author author Daniel Rokhsar, professor of genome and genetics at the University of California said that the sequencing was an opportunity to look at the genome and see what we can learn about the unique brain and morphology of the octopus. Researchers said that the Octopus bimaculoides genome is 2.7 base-pairs in size, with long stretches of repeated sequences. They also identified more than 33,000 protein-coding genes, and found that the genome was smaller in size, but with more genes than the human genome.
Earlier, it was thought that the large size of the octopus genome was caused by genome duplications, but researchers found no evidence of duplication. The expansion of specific gene families caused the evolution of octopus genome. Researchers identified cephalopod-specific genes that exhibited unique features of the octopus such as its slick translucent skin with many suckers.
The team believes that they discovered the genes when it was in its adaptive coloration, when an octopus alters its skin color and texture to blend with the surroundings. The study as published in the journal Nature on August 12.
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