Wired | Science Reveals Yet Another Reason Octopuses and Squid Are So Weird
OCTOPUSES ARE ALIENS living on Earth. They solve puzzles, use tools, and communicate with color. They also squirt ink, open jars, and occasionally pull a prank or two. Given their remarkable intelligence and cunning ways, it takes a lot to surprise the biologists who study these wonderful creatures and their equally weird cousins the squids and cuttlefish.
But when Stanford University geneticist Jin Billy Li heard about Joshua Rosenthal’s work on RNA editing in squid, his jaw dropped. That’s because the work, published today in the journal Cell, revealed that many cephalopods present a monumental exception to how living things use the information in DNA to make proteins. In nearly every other animal, RNA—the middleman in that process—faithfully transmits the message in the genes. But octopuses, squid, and cuttlefish (but not their dumber relatives, the nautiluses) edit their RNA, changing the message that gets read out to make proteins.
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Subbing out one spot in the code may seem like a minor switcheroo, but it can change how—or whether—a protein functions. Theoretically, it changes the genome’s level of complexity: Humans possess just two copies of a given gene, but add a few RNA editing sites and the number of protein variants rises exponentially. An animal could use RNA editing to change how its proteins work if its environment changes. For instance, some RNA in squid get edited when the weather changes so that their proteins work properly at different temperatures.
Xenoporphs:
ReplyDelete"Coleoid cephalopods “change the amino acid code, so you have a big diversification of the proteome, which you don’t see in any other animals,” Marie Öhman, who studies RNA editing in the mammalian brain at Stockholm University in Sweden and did not participate in the work, told The Scientist. “That it’s so extensive is really amazing.”
“When we started looking into this we really didn’t know if this massive recoding was more of a bug or more of a feature,” said coauthor Noa Liscovitch-Brauer, a postdoc at Tel Aviv University in Israel. “What we show here is that it is probably advantageous, and this is something special that only they do.”
“Most organisms have very few functional [editing] sites in coding regions,” said coauthor Eli Eisenberg of Tel Aviv University. “This is why we find it so unusual and surprising that in squid, octopus, and cuttlefish, we see exactly the opposite.”
http://www.the-scientist.com/?articles.view/articleNo/49153/title/Cephalopod-Genomes-Contain-Thousands-of-Conserved-RNA-Editing-Sites/&utm_campaign=NEWSLETTER_TS_The-Scientist-Daily_2016&utm_source=hs_email&utm_medium=email&utm_content=50176304&_hsenc=p2ANqtz-_zXVRRKGZUcnzH1bdKOJyBdOrCfLwE3YT21NWQ-JVdHLArs8k9yRtujXsNkZFvai32ChyJCYlzK1T6oHfgI9jEG159og&_hsmi=50176304
This here is very exciting gain-of-function isht. They change their RNA function based on environmental feedback. Damn. All the genetic engineering going on should take a look at what these beings are up to.
ReplyDeleteMore on the denizens of r'lyeh http://www.popsci.com/octopuses-can-basically-tinker-with-their-own-genes-on-fly#page-4
ReplyDeletehttps://en.wikipedia.org/wiki/R%27lyeh
Are you suggesting that it's a dead-end?
ReplyDeleteNah, I don't believe that evolution proceeds by random mutation. But then, have cephalopod mollusc forms changed dramatically over the course of geologic time?
ReplyDeleteThey haven't. However... they seem incredibly adaptive to a number of different environments. My biggest interest is that it's a new tool to add to the human-driven G.O.D. toolset and maybe an exemplar for protein modification.
ReplyDelete