Scientists at Stanford University have discovered a new “viruslike entity” that is shaped like obelisks.’
Science Magazine reported that a group of scientists from Stanford University unearthed obelisk-shaped viruslike entities that dwell in the human gut and mouth.
According to the team at Stanford, the “obelisks” have genomes that consist of loops of RNA, and sequences belonging to them have been discovered all around the globe.
Gizmodo reported the scientists uncovered almost 30,000 of these special sequences by “analyzing databases that categorized the active genes of gut and mouth microbes, using an algorithm to look for unknown genetic sequences that could represent independent viroid-like loops of RNA.”
In human guts a @Stanford research team found, “nearly 30,000 RNA circles, each consisting of about 1000 bases and likely representing a distinct obelisk. They were unlikely to be bona fide viruses,” but these micro-critters may be altering bacterial activities inside of us. https://t.co/5cnNs9KBqF
— Laurie Garrett (@Laurie_Garrett) January 29, 2024
As they collect and analyze massive amounts of genetic sequences from plants, animals, and microbes, biologists keep encountering surprises, including some that may challenge the very definition of life. The latest, reported this week in a preprint, is a new kind of viruslike entity that inhabits bacteria dwelling in the human mouth and gut. These “obelisks,” as they’re called by the Stanford University team that unearthed them, have genomes seemingly composed of loops of RNA and sequences belonging to them have been found around the world.
Other scientists are delighted by obelisks’ debut. “It’s insane,” says Mark Peifer, a cell and developmental biologist at the University of North Carolina at Chapel Hill. “The more we look, the more crazy things we see.”
It’s not yet known whether obelisks affect human health, says Matthew Sullivan, an integrative biologist at Ohio State University, but they could alter the genetic activity of their bacterial hosts, which in turn could affect human genes.
Most people know RNA, or ribonucleic acid, as DNA’s alter ego—ferrying proteinmaking recipes encoded in a DNA-based gene to molecular “kitchens” outside the cell nucleus that string together a protein’s amino acids. But more than 200 viruses, including those that cause flu, Ebola, and COVID-19, bypass DNA, having genomes composed only of RNA. Their genomes include sequences encoding the proteins that make up a viral shell and ribozymes, enzymes that let a virus copy its original RNA once inside a cell.
“A new kind of viruslike entity that inhabits bacteria dwelling in the human mouth and gut. These “obelisks,”…, have genomes seemingly composed of loops of RNA and sequences belonging to them have been found around the world.https://t.co/SJWaR773st
— Michael Wagner (@MichiWagner4) January 30, 2024