adplus-dvertising
Connect with us

Science

Scientists Revive 46,000-Year-Old Nematodes From Siberian Permafrost – SciTechDaily

Published

 on


Scientists discovered ancient nematodes in the Siberian Permafrost, one of which was identified as a previously undescribed species, Panagrolaimus kolymaensis. The nematodes demonstrated similar survival mechanisms to the model nematode Caenorhabditis elegans. The research indicates that nematodes have developed ways to preserve life over geological time periods, potentially informing conservation strategies in the face of global warming. Credit: Alexei V. Tchesunov and Anastasia Shatilovich / Institute of Physicochemical and Biological Problems in Soil Science RAS

An international research team shows that a newly discovered nematode <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"]”>species from the Pleistocene share a molecular toolkit for survival with the nematode Caenorhabditis elegans.

Some organisms, such as tardigrades, rotifers, and nematodes, can survive harsh conditions by entering a dormant state known as “cryptobiosis.” In 2018, researchers from the Institute of Physicochemical and Biological Problems in Soil Science RAS in Russia found two roundworms (nematode) species in the Siberian Permafrost. Radiocarbon dating indicated that the nematode individuals have remained in cryptobiosis since the late Pleistocene, about 46,000 years ago.

Researchers from the Max Planck Institute of <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Molecular Cell
&lt;em&gt;Molecular Cell&lt;/em&gt; is a peer-reviewed scientific journal that publishes original research articles in the fields of molecular and cellular biology. It covers a wide range of topics related to the molecular mechanisms of biological processes, including gene expression, signal transduction, DNA repair, cell cycle regulation, protein folding and degradation, and many others. &lt;em&gt;Molecular Cell&lt;/em&gt; is one of the top journals in the field of molecular biology and has a high impact factor. The journal also publishes reviews, perspectives, and commentaries that provide critical analysis and synthesis of current research in molecular and cellular biology. The editors of &lt;em&gt;Molecular Cell&lt;/em&gt; aim to promote excellence in the field of molecular biology by publishing innovative and high-quality research that advances our understanding of the molecular mechanisms underlying cellular processes.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>Molecular Cell Biology and Genetics (MPI-CBG) in Dresden, the Center for Systems Biology Dresden (CSBD), and the Institute of Zoology at the University of Cologne, all located in Germany, used genome sequencing, assembly, and phylogenetic analysis and found that the permafrost nematode belongs to a previously undescribed species, Panagrolaimus kolymaensis. They showed that the biochemical mechanisms employed by Panagrolaimus kolymaensis to survive desiccation and freezing under laboratory conditions are similar to those of a life-cycle stage in the important biological model Caenorhabditis elegant.

P. kolymaensis, Female

P. kolymaensis, female. Scanning electron picture. Credit: Alexei V. Tchesunov and Anastasia Shatilovich / Institute of Physicochemical and Biological Problems in Soil Science RAS

Revival and Initial Investigation of the Nematodes

When Anastasia Shatilovich at the Institute of Physicochemical and Biological Problems in Soil Science RAS in Russia revived two frozen individual nematodes from a fossilized burrow in silt deposits in the Siberian permafrost, she and her colleagues were beyond excited. After thawing the worms in the lab, a radiocarbon analysis of plant material from the burrow revealed that these frozen deposits, 40 meters below the surface, had not thawed since the late Pleistocene, between 45,839 and 47,769 years ago.

At the same time, the research group of Teymuras Kurzchalia at the MPI-CBG (Teymuras Kurzchalia is now retired) was already addressing the question of how larval stages of the nematode Caenorhabditis elegans survive extreme conditions. When the team heard about the permafrost nematodes, they immediately reached out for a collaboration with Anastasia Shatilovich.

Collaboration and Further Research

Vamshidhar Gade, a doctoral student at that time in the research group of Teymuras Kurzchalia, started to work with the permafrost nematodes. “What molecular and metabolic pathways these cryptobiotic organisms use and how long they would be able to suspend life are not fully understood,” he says. Vamshidhar is now working at the ETH in Zurich, Switzerland.

Genome Analysis and Species Identification

The researchers in Dresden conducted a high-quality genome assembly of one of the permafrost nematodes in collaboration with Eugene Myers, Director Emeritus and research group leader at the MPI-CBG, the DRESDEN-concept Genome Center, and the research group of Michael Hiller, research group leader at that time at the MPI-CBG and now Professor of Comparative Genomics at the LOEWE-TBG and the Senckenberg Society for Nature Research. Despite having <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"]”>DNA barcoding sequences and microscopic pictures, it was difficult to determine whether the permafrost worm was a new species or not.

Philipp Schiffer, research group leader at the Institute of Zoology, co-lead of the incipient Biodiversity Genomics Center Cologne (BioC2) at the University of Cologne, and expert in biodiversity genomics research, joined forces with the Dresden researchers to determine the species and analyze its genome with his team. Using phylogenomic analysis, he and his team were able to define the roundworm as a novel species, and the team decided to call it “Panagrolaimus kolymaensis.” In recognition of the Kolyma River region from which it originated, the nematode was given the Latin name Kolymaensis.

Survival Mechanism and Potential Implications

By comparing the genome of Panagrolaimus kolymaensis with that of the model nematode Caenorhabditis elegans, the researchers in Cologne identified genes that both species have in common and that are involved in cryptobiosis. To their surprise, most of the genes necessary for entering cryptobiosis in Caenorhabditis elegans so-called Dauer larvae were also present in Panagrolaimus kolymaensis.

Next, the research team evaluated Panagrolaimus kolymaensis’s ability to survive and discovered that mild dehydration exposure before freezing helped the worms prepare for cryptobiosis and increased survival at -80 degrees <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Celsius
The Celsius scale, also known as the centigrade scale, is a temperature scale named after the Swedish astronomer Anders Celsius. In the Celsius scale, 0 °C is the freezing point of water and 100 °C is the boiling point of water at 1 atm pressure.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>Celsius. At a biochemical level, both species produced a sugar called trehalose when mildly dehydrated in the lab, possibly enabling them to endure freezing and intense dehydration. Caenorhabditis elegans larvae also benefited from this treatment, surviving for 480 days at -80 degrees Celsius without suffering any declines in viability or reproduction following thawing.

Revelations

According to Vamshidhar Gade and Temo Kurzhchalia, “Our experimental findings also show that Caenorhabditis elegans can remain viable for longer periods in a suspended state than previously documented. Overall, our research demonstrates that nematodes have developed mechanisms that allow them to preserve life for geological time periods.”

“Our findings are essential for understanding evolutionary processes because generation times can range from days to millennia and because the long-term survival of a species’ individuals can result in the re-emergence of lineages that would otherwise have gone extinct,” concludes Philipp Schiffer, one of the authors who oversaw the study.

Eugene Myers adds: “P. kolymaensis‘s highly contiguous genome will make it possible to compare this feature to those of other Panagrolaimus species whose genomes are presently being sequenced by Schiffer’s team and colleagues.” Philipp Schiffer is convinced that “studying the adaptation of species to such extreme environments by analyzing their genomes will allow us to develop better conservation strategies in the face of global warming.”

Teymuras Kurzchalia says: “This study extends the longest reported cryptobiosis in nematodes by tens of thousands of years.”

Reference: “A novel nematode species from the Siberian permafrost shares adaptive mechanisms for cryptobiotic survival with C. elegans dauer larva” by Anastasia Shatilovich, Vamshidhar R. Gade, Martin Pippel, Tarja T. Hoffmeyer, Alexei V. Tchesunov, Lewis Stevens, Sylke Winkler, Graham M. Hughes, Sofia Traikov, Michael Hiller, Elizaveta Rivkina, Philipp H. Schiffer, Eugene W. Myers and Teymuras V. Kurzchalia, 27 July 2023, PLoS Genetics.
DOI: 10.1371/journal.pgen.1010798

This work was supported by the Russian Foundation fr Basic Research (19-29-05003-mk) to AS and ER. VRG and TVK acknowledge the financial support from the Volkswagen Foundation (Life research grant 92847). PHS and TTH are supported by a DFG ENP grant to PHS (DFG project 434028868). GMH is funded by a UCD Ad Astra Fellowship. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Adblock test (Why?)

728x90x4

Source link

Continue Reading

Science

The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

Published

 on

 

NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

The Canadian Press. All rights reserved.

Source link

Continue Reading

News

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

Published

 on

 

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.

Source link

Continue Reading

News

B.C. sets up a panel on bear deaths, will review conservation officer training

Published

 on

 

VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

The Canadian Press. All rights reserved.

Source link

Continue Reading

Trending