Evolution: viruses critical role (Introduction)

by David Turell , Monday, September 07, 2020, 18:50 (1319 days ago) @ David Turell

The latest research:

https://phys.org/news/2020-09-viruses-critical-role-evolution-survival.html

"In two separate papers appearing in the same edition of the journal, they reveal two distinct and fundamental processes underlying germline transcriptomes. They also show that species-specific transcriptomes are fine-tuned by endogenous retroviruses in the mammalian germline

"Germline transcriptomes include all the messenger RNA in germline cells, which contain either the male or female half of chromosomes passed on as inherited genetic material to offspring when species mate. This means that germline transcriptomes define the unique character of sperm and egg to prepare for the next generation of life.

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"'One paper, Maezawa and Sakashita et al., explores super-enhancers, which are robust and evolutionally conserved gene regulatory elements in the genome. They fuel a tightly regulated burst of essential germline genes as sperm start to form," Namekawa said.

"'The second study, Sakashita et al., involves endogenous retroviruses that act as another type of enhancer—gene regulatory elements in the genome—to drive expression of newly evolved genes. This helps fine tune species-specific transcriptomes in mammals like humans, mice, and so on.

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"Viruses, especially endogenous retroviruses (ERVs) that are an inherent part of mammalian biology, can dramatically influence gene expression, investigators report. ERVs are molecular remnants of retroviruses that infect the body and over time incorporate into the genome.

"'What we learn from our study is that, in general, viruses have major roles in driving evolution," Namekawa explained. "In the long-term, viruses have positive impacts to our genome and shape evolution."

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"Those tests revealed that the the genome-wide reorganization of super-enhancers drives bursts of germline gene expression after germ cells enter meiosis, a specialized form of cell division that produces the haploid genome of germ cells.

"The study further demonstrates the molecular process through whichsuper-enhancer switching takes place in germ cells. Super-enhancers are regulated by two molecules that act as gene-burst control switches—the transcription factor A-MYB and SCML2, a critical silencing protein in sperm formation.

"Endogenous retroviruses are a group of transposable elements (TEs), mobile genetic elements that account for approximately 40-50 percent of a given mammalian genome. Also referred to as "jumping genes," TEs have long been considered genetic threats because transposition can be harmful if, for example, the process disrupts protein-coding genes.

"Building on findings from the 1950s that TEs can function as genetic regulatory elements, Namekawa and his collaborators (Sakashita et al.) produced data showing that ERV-driven mechanisms help fine tune species-specific transcriptomes."

Comment: Why viruses has always been a question looking at God's purposes in evolution. Covid shows they can be nasty just as some bacteria infections. But we now know about necessary biomes and it turns viruses are very useful also. The moral is God knows exactly what He is doing and how to produce the results He desires. More research always answers negative questioning about Gods methods.