Evolution and humans: role of viruses & complex life (Evolution)

by David Turell , Thursday, June 18, 2020, 21:45 (1617 days ago) @ David Turell

The previous article showed viruses ability to advance evolution but viruses subverted that ability to invent virus/human genome code for their lone benefit:

https://www.sciencedaily.com/releases/2020/06/200618120213.htm

"...researchers have shown that a large group of viruses, including the influenza viruses and other serious pathogens, steal genetic signals from their hosts to expand their own genomes.

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"They showed that, by stealing genetic signals from their hosts, viruses can produce a wealth of previously undetected proteins. The researchers labeled them as UFO (Upstream Frankenstein Open reading frame) proteins, as they are encoded by stitching together the host and viral sequences. There was no knowledge of the existence of these kinds of proteins prior to this study.

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"Viruses cannot build their own proteins, so they need to feed suitable instructions to the machinery that builds proteins in their host's cells. Viruses are known to do this through a process called "cap-snatching," in which they cut the end from one of the cell's own protein-encoding messages (a messenger RNA, or mRNA) and then extend that sequence with a copy of one of their own genes. This gives a hybrid message to be read.

"'For decades we thought that by the time the body encounters the signal to start translating that message into protein (a 'start codon') it is reading a message provided to it solely by the virus. Our work shows that the host sequence is not silent," said Dr. Marazzi.

"The researchers show that, because they make hybrids of host mRNAs with their own genes, viruses (sNSVs) can produce messages with extra, host-derived start codons, a process they called "start snatching." This makes it possible to translate previously unsuspected proteins from the hybrid host-virus sequences. They further show that these novel genes are expressed by influenza viruses and potentially a vast number of other viruses. The product of these hybrid genes can be visible to the immune system, and they can modulate virulence.

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"'Viruses take over their host at the molecular level, and this work identifies a new way in which some viruses can wring every last bit of potential out of the molecular machinery they are exploiting. While the work done here focusses on influenza viruses, it implies that a huge number of viral species can make previously unsuspected genes.'"

Comment: In view of what is known about viruses, this finding is not surprising. It also shows, as with metabolic errors, what God created in the biochemistry of viruses for evolution can also have errors or undesired results.