Nature Briefings upsets the apple cart. Big Time

What if everything you learned forty and fifty years ago was wrong? Where would you be then. Something a bit like that happened to us this week when we read this piece from Nature Briefings, Bizarre bacteria scramble workflow of life

Bacteria have stunned biologists by reversing the usual flow of information. Typically genes written in DNA serve as the template for making RNA molecules, which are then translated into proteins. Some viruses are known to have an enzyme that reverses this flow by scribing RNA into DNA. Now scientists have found bacteria with a similar enzyme that can even make completely new genes — by reading RNA as a template. These genes create protective proteins when a bacterium is infected by a virus. “It should change the way we look at the genome,” says biochemist and study co-author Samuel Sternberg.Nature | 4 min read
Reference: bioRxiv preprint (not peer reviewed)
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 Nature Briefing: Microbiology

When we were young, there was a central doctrine in biology. Information was stored in genes, deep in the cell nucleus. These were made of DNA. This information was turned into RNA, then used to make proteins. The DNA code was unchangeable, inviolate which made the operations of natural selection all the easier to facilitate. If a large cat suddenly developed DNA to give it stripes, then it could hide better in the jungle, and pass on more copies of the DNA. Hence tigers evolved. Job done. To think the DNA could be modified by some environmental feedback was not only Lamarckian heresy, there was no obvious mechanism by which it could come about.

Now we are Not saying that the above discoveries overthrow the central tenet. Not yet. But remember how the Michelson Morley experiment in the 1880s posed a deep, unanswerable question at the heart of physics which was not fully resolved until Einstein came along a generation or so later. And we are certainly not going to make impulsive conclusions . But our story today, combined with all the recent advances in Epigenetics, do suggest however that the old model is now awaiting a major rethink.

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