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Breaking the Rules – Important Molecular Pathway for Control of Aging Discovered – SciTechDaily

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New research found that imbalances in RNA communication, both within and from outside the organism, can shorten the lifespan of Caenorhabditis elegans, offering new insights into the aging process and genetic regulation.

Research on the roundworm species C. elegans has demonstrated that disruptions in the transfer of RNA between cells across various tissues can lead to a shortened lifespan.

Cells in various tissues interact by sharing <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

RNA
Ribonucleic acid (RNA) is a polymeric molecule similar to DNA that is essential in various biological roles in coding, decoding, regulation and expression of genes. Both are nucleic acids, but unlike DNA, RNA is single-stranded. An RNA strand has a backbone made of alternating sugar (ribose) and phosphate groups. Attached to each sugar is one of four bases—adenine (A), uracil (U), cytosine (C), or guanine (G). Different types of RNA exist in the cell: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA).

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]” tabindex=”0″ role=”link”>RNA molecules. A study conducted by scientists from the State University of Campinas (UNICAMP) in Brazil, using the roundworm <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

species
A species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]” tabindex=”0″ role=”link”>species Caenorhabditis elegans, discovered that disruptions in this method of communication can lead to a reduced lifespan for the organism. The study was recently published in the journal Gene. The findings contribute to a better understanding of the aging process and associated diseases.

“Previous research showed that some types of RNA can be transferred from one cell to another, mediating intertissue communication, of the kind that occurs with proteins and metabolites, for example. This is considered a mechanism for signaling between organs or neighboring cells. It’s part [of the physiopathology] of several diseases and of the organism’s normal functioning,” said Marcelo Mori, corresponding author of the article and a professor at the Institute of Biology (IB-UNICAMP). “What wasn’t clear and we’ve now succeeded in proving is that changes in the pattern of this ‘conversation’ between RNA molecules can affect aging.”

The study was conducted at UNICAMP’s Obesity and Comorbidities Research Center (OCRC), one of the Research, Innovation, and Dissemination Centers (RIDCs) funded by FAPESP. It was also funded via a project for which Mori is the principal investigator.

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“This communication mechanism has to be well adjusted to give the organism an adequate lifespan. In the study, we found that if any tissue happens to increase its capacity to absorb some types of RNA from the extracellular medium, this ends up having an impact on the organism’s lifespan,” Mori said.

The researchers demonstrated that the reduction in lifespan was due not only to the disruption of RNA-based communication between tissues in the same organism, he added, but also to an increase in the capacity for RNA uptake from the environment – bacteria in microbiota, for example. As they explain in the article, “Our data support the notion that systemic RNA signaling must be tightly regulated, and unbalancing that process provokes a reduction in lifespan. We termed this phenomenon Intercellular/Extracellular Systemic RNA imbalance (InExS).”

Breaking the rules

Mori explained that the decision to research the intercellular RNA transport mechanism was inspired by the discovery of RNA interference, for which American scientists Andrew Fire and Craig Mello won the 2006 Nobel Prize in Physiology and Medicine. They injected double-stranded RNA into C. elegans to “silence” genes with great precision. “They found that the silencing mechanism affected genes in other tissues as well as the tissue involved and that it was transmitted to following generations,” he said.

The discovery of RNA interference elucidated the mechanisms underlying RNA transfer between cells in an organism and between the organism and the environment. It also relativized a central dogma of molecular biology. Until then, the information embodied by the genetic code was believed to flow only from <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

DNA
DNA, or deoxyribonucleic acid, is a molecule composed of two long strands of nucleotides that coil around each other to form a double helix. It is the hereditary material in humans and almost all other organisms that carries genetic instructions for development, functioning, growth, and reproduction. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]” tabindex=”0″ role=”link”>DNA to RNA, and from there to proteins, but the work of Fire and Craig revealed that double-stranded RNA can block this flow. Messenger RNA is destroyed by RNA interference, which silences specific genes without altering the DNA sequence, showing that RNA can also perform a regulatory function in the genome. Although the human genome comprises some 30,000 genes, only a few are used in each cell to synthesize proteins. A large proportion play a regulatory role, influencing the expression of other genes.

Balance is all

“We wanted to understand how this process could interfere with important physiological functions linked to aging. In C. elegans, RNA transfer between cells involves what are known as systemic RNA interference defective (SID) genes [responsible for different stages in RNA absorption and export]. We observed that a gene expression pattern associated with this pathway in specific tissues changed during aging. The messenger RNA that encodes the protein SID-1 [fundamental to cellular uptake of RNA], for example, increased in some tissues and decreased in others,” Mori said.

To find out more about the role of RNA in intertissue signaling, the researchers conducted experiments in which they manipulated the expression of the protein SID-1 in specific tissues of C. elegans, such as neuronal, intestinal, and muscle cells, in order to change its function.

“We found mutants without the SID-1 function to be as healthy as wild-type worms, whereas overexpression of SID-1 in the gut, muscles, or neurons shortened the lifespan of the worms concerned. We also found that a lifespan reduction correlated with overexpression of other proteins in the RNA transport pathway, such as SID-2 and SID-5,” he said.

The dysregulation may reside in the distribution of RNA to tissue. “To dysregulate RNA distribution in the worms, we increased SID-1 expression in specific tissues [gut, muscles, and neurons] and found that channeling it to a specific organ led to a lifespan reduction,” he said.

“We also showed that this imbalance in RNA transfer led to loss of function in the pathway that produces microRNAs [small pieces of non-coding RNA with a regulatory function]. It’s as if the larger number of RNAs transported to these tissues created a kind of competition in which the production of microRNAs was the loser. Previous research had already shown that loss of function in microRNA production led to a reduction of lifespan.”

The UNICAMP group also investigated exogenous RNA transfer (between the outside environment and the organism). As in the previous experiments, a reduction of lifespan correlated with overexpression of SID-2, which mediates RNA uptake from the gut, and with excessive RNA production by bacteria on which the worms feed and which end up in its gut microbiota.

“We believe the worms may use exogenous RNA to monitor microorganisms in the environment, but negative effects may ensue when excessive amounts are absorbed by their tissue,” Mori said. “When we forced bacteria in the laboratory to express more double-stranded RNA, the worms’ lifespan decreased. Excessive RNA transfer interferes with homeostasis and endogenous RNA production, accelerating the aging process.”

Reference: “Tissue-specific overexpression of systemic RNA interference components limits lifespan in C. elegans” by Henrique Camara, Mehmet Dinçer Inan, Carlos A. Vergani-Junior, Silas Pinto, Thiago L. Knittel, Willian G. Salgueiro, Guilherme Tonon-da-Silva, Juliana Ramirez, Diogo de Moraes, Deisi L. Braga, Evandro A. De-Souza and Marcelo A. Mori, 18 November 2023, Gene.
DOI: 10.1016/j.gene.2023.148014

The study was funded by the São Paulo Research Foundation.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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