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When ribosomes go rogue

In the 1940s, scientists at the recently established National Cancer Institute were trying to breed mice that could inform our understanding of cancer, either because they predictably developed certain cancers or were surprisingly resistant.

The team spotted a peculiar litter in which some baby mice had short, kinked tails and misplaced ribs growing out of their neck bones. The strain of mice, nicknamed “tail short,” has been faithfully bred ever since, in the hope that one day, research might reveal what was the matter with them.

After more than 60 years, researchers finally got their answer, when Maria Barna, a developmental biologist then at the University of California San Francisco, found that the mice had a genetic mutation that caused a protein to disappear from their ribosomes—the places in cells where proteins are made.

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Medicine Nobel goes to previously unknown way of controlling genes

7 October 2024 at 17:40

On Monday, the Nobel Committee announced that two US researchers, Victor Ambros and Gary Ruvkun, will receive the prize in Physiology or Medicine for their discovery of a previously unknown mechanism for controlling the activity of genes. They discovered the first of what is now known to be a large collection of MicroRNAs, short (21-23 bases long) RNAs that bind to and alter the behavior of protein-coding RNAs. While first discovered in a roundworm, they've since been discovered to play key roles in the development of most complex life.

The story behind the discovery is typical of a lot of the progress in the biological sciences: genetics helps identify a gene important for the development of one species, and then evolutionary conservation reveals its widespread significance.

In the worm

Ambros and Ruvkun started on the path to discovery while post-doctoral fellows in the lab of earlier Nobel winner Robert Horvitz, who won for his role in developing the roundworm C. elegans as an experimental genetic organism. As part of the early genetic screens, people had identified a variety of mutations that caused developmental problems for specific lineages of cells. These lin mutations included lin-4, which Ambros was characterizing. It lacked a number of specialized cell types, as well as the physical structures that depended on them.

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US prepares for bird flu pandemic with $176M Moderna vaccine deal

By: Beth Mole
2 July 2024 at 19:14
US prepares for bird flu pandemic with $176M Moderna vaccine deal

Enlarge (credit: Getty | Justin Sullivan)

The US government will pay Moderna $176 million to develop an mRNA vaccine against a pandemic influenza—an award given as the highly pathogenic bird flu virus H5N1 continues to spread widely among US dairy cattle.

The funding flows through BARDA, the Biomedical Advanced Research and Development Authority, as part of a new Rapid Response Partnership Vehicle (RRPV) Consortium. The program is intended to set up partnerships with industry to help the country better prepare for pandemic threats and develop medical countermeasures, the Department of Health and Human Services said in a press announcement Tuesday.

In its own announcement on Tuesday, Moderna noted that it began a Phase 1/2 trial of a pandemic influenza virus vaccine last year, which included versions targeting H5 and H7 varieties of bird flu viruses. The company said it expects to release the results of that trial this year and that those results will direct the design of a Phase 3 trial, anticipated to begin in 2025.

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DNA-based bacterial parasite uses completely new DNA-editing method

26 June 2024 at 19:31
Top row: individual steps in the reaction process. Bottom row: cartoon diagram of the top, showing the position of each DNA and RNA strand.

Enlarge / Top row: individual steps in the reaction process. Bottom row: cartoon diagram of the top, showing the position of each DNA and RNA strand. (credit: Hiraizumi, et. al.)

While CRISPR is probably the most prominent gene-editing technology, there are others, some developed before and since. And people have been developing CRISPR variants to perform more specialized functions, like altering specific bases. In all of these cases, researchers are trying to balance a number of competing factors: convenience, flexibility, specificity and precision for the editing, low error rates, and so on.

So, having additional options for editing can be a good thing, enabling new ways of balancing those different needs. On Wednesday, a pair of papers in Nature describe a DNA-based parasite that moves itself around bacterial genomes through a mechanism that hasn't been previously described. It's nowhere near ready for use in humans, but it may have some distinctive features that make it worth further development.

Going mobile

Mobile genetic elements, commonly called transposons, are quite common in many species—they make up nearly half the sequences in the human genome, for example. They are indeed mobile, showing up in new locations throughout the genome, sometimes by cutting themselves out and hopping to new locations, other times by sending a copy out to a new place in the genome. For any of this to work, they need to have an enzyme that cuts DNA and specifically recognizes the right transposon sequence to insert into the cut.

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Mutations in a non-coding gene associated with intellectual disability

31 May 2024 at 17:30
Colored ribbons that represent the molecular structure of a large collection of proteins and RNAs.

Enlarge / The spliceosome is a large complex of proteins and RNAs. (credit: NCBI)

Almost 1,500 genes have been implicated in intellectual disabilities; yet for most people with such disabilities, genetic causes remain unknown. Perhaps this is in part because geneticists have been focusing on the wrong stretches of DNA when they go searching. To rectify this, Ernest Turro—a biostatistician who focuses on genetics, genomics, and molecular diagnostics—used whole genome sequencing data from the 100,000 Genomes Project to search for areas associated with intellectual disabilities.

His lab found a genetic association that is the most common one yet to be associated with neurodevelopmental abnormality. And the gene they identified doesn’t even make a protein.

Trouble with the spliceosome

Most genes include instructions for how to make proteins. That’s true. And yet human genes are not arranged linearly—or rather, they are arranged linearly, but not contiguously. A gene containing the instructions for which amino acids to string together to make a particular protein—hemoglobin, insulin, albumin, whatever protein you like—is modular. It contains part of the amino acid sequence, then it has a chunk of DNA that is largely irrelevant to that sequence, then a bit more of the protein’s sequence, then another chunk of random DNA, back and forth until the end of the protein. It’s as if each of these prose paragraphs were separated by a string of unrelated letters (but not a meaningful paragraph from a different article).

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Echoes of the Forgotten Realm

17 March 2024 at 10:42

anime-style graphic capturing the climax of "Echoes of the Forgotten Realm," with Rowan, Lyra, and Thorne in the mythical city of Lyrath, awakening the guardians of Eldoria. Their unity and determination shine as they push back the consuming shadows, bringing hope to the realm


 In the shadowed lands of Eldoria, a realm forgotten by time and veiled in the mists of legend, there emerged a tale of courage, mystery, and the quest for a lost legacy. This story centers on Rowan, a young scholar with an insatiable curiosity about the world's ancient secrets and a hidden lineage that ties him to Eldoria's most powerful guardians.

Rowan's life took a dramatic turn when he discovered an old map among his late grandfather's belongings, revealing the location of the mythical city of Lyrath, long thought to be a mere fable. The city was said to house the Crystal of Aeterna, a relic of immense power that could awaken the guardians of Eldoria, beings of pure elemental energy who once protected the realm from the shadows that sought to consume it.

Determined to uncover the truth of his heritage and the secrets of Lyrath, Rowan embarked on a journey that led him into the heart of darkness, the very shadows that his ancestors had fought to keep at bay. Along his path, he was joined by Lyra, a rogue with unmatched agility and a mysterious past of her own, and Thorne, a mage whose connection to the natural elements of Eldoria was unparalleled.

Together, they navigated treacherous landscapes, from the Whispering Forest, where the trees themselves seemed to watch their every move, to the Shattered Peaks, mountains that tore at the sky with their jagged spires. They encountered creatures of myth and legend, some allies, some foes, all part of the rich tapestry of Eldoria's forgotten realm.

As they neared Lyrath, the shadows grew more desperate, unleashing their minions in an attempt to thwart Rowan's quest. It was in these moments of peril that the true strength of the group's bond and their individual powers were tested. Rowan's leadership, Lyra's cunning, and Thorne's wisdom combined to overcome each challenge, bringing them closer to the Crystal of Aeterna.

The climax of their adventure unfolded within the ancient walls of Lyrath, where Rowan faced the darkness that had plagued Eldoria for centuries. In a moment of unity and sacrifice, Rowan and his companions awakened the guardians, using the Crystal of Aeterna not as a weapon of destruction but as a beacon of hope. Light returned to Eldoria, revealing the realm's true beauty and heritage, long shrouded in shadow.

"Echoes of the Forgotten Realm" became a legend, a reminder of the power of curiosity, bravery, and the enduring light within the darkness. Rowan's journey from scholar to hero inspired those who heard his tale to believe in the magic that lies in seeking the truth and fighting for what is right.

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