"Giant viruses may play an intriguing role in evolution " Topic

…of life on Earth

"In a new study, a University of Iowa biologist identified a virus family whose set of genes is similar to that of eukaryotes, an organism classification that includes all plants and animals.

The finding is important because it helps clarify how eukaryotes evolved after branching from prokaryotes some 2 billion years ago.

"It's exciting and significant to find a living family of giant viruses with eukaryote-specific genes in a form that predates the latest common ancestor of all eukaryotes," says Albert Erives, associate professor in the Department of Biology. "These viruses are like time machines that tell us more about how life on our planet came to be."

In the study, Erives analyzed the genome of a virus family called Marseilleviridae and found it shares a similar set of genes, called core histones, with eukaryotes…"
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Amicalement
Armand

I know that a Paramecium isn't a virus but I always had nightmares about a giant one going through space gobbling up planets and civilizations. Or maybe it was an amoeba.

Anyway, I probably watched a horror movie that I shouldn't have when I was a really small kid … or something like that. :)

Dan

Dan was that not a Star Trek episode?

Oh my God. You might be right!

Dan

Giant viruses must have been what killed-off the giants. And this begs the question(or not) was Hagrid immune?

Star Trek TOS
Immunity Syndrome

Hey Dan, oddly enough these Megavirales actually are found infecting amoeba.

More info here:

link

Bowman, fascinating info. Thanks

TNE2300, that's exactly the bright neon-outlined image I recall, except I completely blocked out the Enterprise. Thanks.

Dan

Ok, some free form conjecturing here, in case anyone is interested.

So the first fossils of eukaryotes are found at about 2.1 billion years ago. Scientists think that eukaryotes existed about 2.7 bya, but getting fossils of soft skinned single celled creatures with organelles is very rare.

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So let's say 2.7 bya, large prokaryotes get invaded by smaller prokaryotes which begin a symbiotic relationship to form the first eukaryotes. At the same time, viruses evolve that can infect these new hybrid creatures. Among these viruses are the Megaviridae or giant viruses. These viruses seem to have some metabolic independence from their victims. For the link above:

"Mimivirus genes were found to encode proteins unique amongst viruses and involved in DNA repair, protein folding, nucleotide synthesis, amino acid metabolism, protein modification, or lipid or polysaccharide metabolisms"

In our time these viruses seem only to attack the most simple of all the Eukaryotes, the unicelluler Amoebi. The modern day amoeba, while 2.7 billion years farther along, is the closest living organism to the first eukaryotes.

But the viruses that evolved to attack modern, more advanced organisms, such as Influenza, Smallpox, the common cold are much simpler in design and do not contain any of the above genes. Does this mean modern viruses (that plague humans) lost the ability to internally control their own metabolism and, instead, gained the ability to fully exploit the manufacturing processes within the target cells? In other words the more modern viruses have given up some metabolic autonomy in return for more efficiently utilizing the metabolism mechanisms of their host cells.

Thanks Bowman….

Amicalement
Armand