Researchers find link in how cells start process necessary for life

Researchers have found an RNA structure-based signal that spans billions of years of evolutionary divergence between different types of cells, according to a study led by researchers at the University of Colorado School of Medicine at the Anschutz Medical Campus and published in the journal Nature.

The finding could alter the basic understanding of how two distinct life forms - and eukaryotes - begin the process of protein synthesis.

Jeffrey Kieft, PhD, professor of biochemistry and molecular genetics and corresponding author of the article in Nature, said scientists have long thought that the molecular signals that initiate protein synthesis in bacteria and eukaryotes are mutually exclusive. Scientists in Kieft's lab explored whether a structured RNA molecule from a virus that infects could function in bacteria. Surprisingly, they found that it could initiate syntheses, a process necessary for life.

"What we found bridges billions of years of evolutionary divergence," said Kieft, who is also a Howard Hughes Medical Institute Early Career Scientist. "We wanted to explore whether it was possible to bypass mechanisms that were specific to each domain of life and find a signal capable of operating in both."

Eukaryotes are organisms, such as plants, animals and fungi, whose cells contain a nucleus and are enclosed within membranes, while prokaryotes, such as bacteria, do not contain a nucleus.

In an article that accompanies the study by Kieft and his colleagues, Eric Jan, associate professor in the Department of Biochemistry and Molecular Biology at the University of British Columbia, calls the finding "surprising" and writes that the CU scientists and their colleagues "have shown for the first time that a bona fide signal in an RNA structure promotes in the two domains of life."


Explore further

Trying to halt hepatitis C's molecular hijacking

Journal information: Nature

Citation: Researchers find link in how cells start process necessary for life (2015, February 11) retrieved 19 August 2019 from https://phys.org/news/2015-02-link-cells-life.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
33 shares

Feedback to editors

User comments

Feb 11, 2015
If Eukaryotic cells evolved from Prokaryotic cells, then its quite flawed to assume all of their genetic signaling is 100% mutually exclusive.

Feb 12, 2015
Missing link to paper: http://www.nature...219.html ]

It is hard what to make of this.

The difference between prokaryotic and eukaryotic tranlation initiation isn't that large, mainly the eukaryotic has more bling. (A special nucleotide cap and initiation assembly at the mRNA end, then ratcheting away until the gene start vs assembly at the start for prokaryotes; http://en.wikiboo...nslation ]

And there are many IRES mechanisms. [ http://viralzone....867.html ]

On the other hand, virus IRES initiation is widespread, as is eukaryote. And precisely the +ssRNA virusal clade the paper takes its IRES from is the large viral clade, so most ancient, and with its + (sense)-strand rewritten to directly produce + (sense) mRNA genes as the genes would be in RNA world.

[tbctd]

Feb 12, 2015
[ctd]
Perhaps we are seeing a preserved RNA world initial protein translation process, that later became replaced by the prokaryote type translation initiation.

Either prokaryotes lost the initial version (more unlikely) or eukaryotes recaptured it by horizontal gene transfer from viruses. Or prokaryotes have unidentified IRES mechanisms...

JVK
Feb 16, 2015
Ecological variation is linked from atoms to ecosystems and adaptations via changes in the nutrient-dependent viral microRNA/messenger RNA balance.

Viruses alter RNA-mediated cell type differentiation that is perturbed due to nutrient stress.

Typically, the finely-tuned microRNA/messenger RNA balance is maintained by RNA-directed DNA methylation and fixation of RNA-mediated amino acid substitutions. The nutrient-dependent substitutions benefit the biophysically constrained chemistry of protein folding that is required to link thermodynamic cycles of protein biosynthesis and degradation to organism-level thermoregulation in all genera.

The complexity of the links from RNA to metabolic networks to the de novo creation of genetic networks has been dismissed by theorists who make claims about beneficial mutations.

No experimental evidence shows a link from the sun's biological energy and nutritional epigenetics to evolution via constraint-breaking mutations.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more