White-nose syndrome in little brown bats: how to protect them


By USFWS/Ann Froschauer – File:Little_brown_bat_(7408990420).jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=74837638

In a recent study, scientists discovered that white-nose syndrome (WNS)-affected little brown bats significantly boosted their foraging activities at artificial insect buffets. Bats will be able to boost their fat reserves before and during hibernation thanks to the bug buffets, which are situated close to hibernation areas. They should be able to survive the illness as a result.

For bats with WNS, hibernation is extremely dangerous since the condition interferes with hibernation. Bats may thus awaken while hibernating, which might result in malnutrition, dehydration, and ultimately death.

The study is a distinctive and novel experiment that was published in Ecological Solutions and Evidence. It is non-invasive, targets increasing conservation efforts for winter colonies at danger of WNS, and offers a consistent food supply—important in the winter when bugs are limited.

Bat Conservation International’s lead scientist, Dr. Winifred Frick, revealed that bats ate three to eight times more than normal when they set up bug buffets. In doing so, they anticipate that bats will consume more, put on more weight, and recover from WNS more quickly.

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One of the deadliest animal illnesses in recent memory is WNS. Several hibernating North American bat species, including the little brown bat, have seen significant reductions as a result. The species, which was formerly the most prevalent bat in North America, has lost more than 90% of its population as a result of WNS. Finding innovative ways to counteract the negative effects of WNS is essential since bats are a vital component of healthy ecosystems.

Researchers wanted to know if the tiny brown bats would come to the artificial insect buffets where the bugs got attracted by light lures. The echolocation sounds and feeding buzzes that the bats made while foraging were recorded and counted to determine foraging activity.

They then compared these figures with those obtained from areas lacking insect buffets. According to the findings, bats were foraging at considerably greater rates in insect buffet locations than in those without.

These findings suggest that boosting the number of bugs accessible to bats close to their winter homes will benefit in the fight against WNS, according to Dr. Frick.

The issue of WNS in North American bats may be addressed with realistic and scalable conservation measures, according to Christian Newman, technical executive for endangered and protected species at the Electrical Power Research Institute.

This paper’s publication corresponds with bats getting ready to come out of hibernation. Long-term goals include creating insect buffets and assisting bats throughout their area to live close to places where they hibernate.

Sources:

Winifred F. Frick et al. (2023). Bats increased foraging activity at experimental prey patches near hibernacula, Ecological Solutions and Evidence. DOI: 10.1002/2688-8319.12217

https://phys.org/news/2023-03-brown-white-nose-syndrome.html

The high acidity of a cynipid wasp’s gall may be a new way to defend against predators


Oak galls. By Dazzii – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=37898317

A tiny insect known as a cynipid wasp has a larva that was recently found generating plant growths known as galls that possessed acidity levels comparable to lemons.

Entomologist at Penn State and main author of an article on the discovery that was published on March 1 in Biology Letters, Antoine Guiguet, noted that it is a unique defense system that has never been observed before.

It has long been known that the majority of cynipid wasp species inject chemicals into oak trees’ leaves to cause the formation of protective galls (or growths) around their larvae, ensuring the security of their growing young. The gall functions as a protective mechanism to ward off natural enemies while housing and feeding the insects as they develop. The wasp larva ultimately eat their way out of the galls as they fall off the tree, leaving the little balls left to decay on the forest floor.

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As all of this activity requires chemistry, tannins, which build up on the gall’s surface and protect it from herbivore attack, have generally been the principal defensive compounds found in galls. In fact, the tannin content of oak galls is so high that when they are crushed and soaked in water, they produce a dark brown liquid that serves as the foundation of a lasting ink that was once used to write the U.S. Declaration of Independence, Constitution, and Bill of Rights.

John Tooker, an entomology professor at Penn State and a co-author on the paper, said that it is really amazing because here is an animal utilizing chemistry to force a plant to do its bidding. The nutritional hypothesis for why galls evolved is explained by the insect’s ability to direct the plant to produce the precise food it needs. Nevertheless, this explanation must certainly be linked with a defense strategy since if you have a good food supply, other organisms will want to consume it.

The wasp decreased the pH level of the inside of their growing gall to the acidity levels adopted by pitcher plants in their study, which may be a unique manipulation of host-plant chemistry in transparent oak galls.

The researchers are aware that plants seldom have pH levels this low, according to Tooker.  “Furthermore, the pH value that the researchers obtained was comparable to the acidity of the contents of a pitcher plant, which is about equivalent to a lemon. They  believe that this serves a defensive purpose. That acidic climate would discourage anything from boring in there.

Mass spectrometry, an analytical method used for the study of chemical compounds, was employed by the researchers to determine the amount of organic acid present in the transparent oak gall and to compare it to fruits and other galls. They discovered that 66% of the organic acid identified in the galls is malic acid, an acid that is particularly abundant in apples. In comparison to other galls and apples, the concentration of malic acid was two times greater. Also, they discovered that the gall’s pH ranged from 2 to 3, which is among the lowest values discovered in plant tissues.

Malic acid, which is present in all plant and animal cells, even if in small amounts, is a crucial component of cell metabolism, according to Guiguet. What’s astonishing is that this wasp is able to induce its accumulation in the vacuole, a storage space found in plant cells.

The transparent oak gall is one of the most acidic plant tissues ever recorded, with a pH of less than 3. Only citrus fruit tissues were known to be capable of this extreme acidity prior to this finding.

The scientists speculate that the wasp may have produced acidic galls as a substitute for the tannin buildup seen in the majority of other oak galls. They claimed that because caterpillar hindguts are quite alkaline, low pH might impair the effectiveness of protein digestion in insects similarly to tannins.

Contrary to tannins, acidic conditions may also be effective at repelling parasitoid wasps—the primary predators of cynipid wasps—by degrading the tissue of the organ that some parasitoid wasp species use as a needle to lay their eggs in the gall.

Cynipid wasps produce galls by a chemical mechanism that is yet unknown as stated by Guiguet. Now that the researchers have demonstrated that the wasp have developed with the ability to modify pH, they have contributed to this enigma.

Sources:

Antoine Guiguet et al, Extreme acidity in a cynipid gall: a potential new defensive strategy against natural enemies, Biology Letters (2023). DOI: 10.1098/rsbl.2022.0513

https://phys.org/news/2023-03-wasps-harness-power-pitcher-first-ever.html

Researchers have found a new way for algae and fungi to live together


https://www.nature.com/articles/s41598-023-29384-4/
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The symbiotic interaction between fungus and algae, which science has mostly ignored up until now, has been detailed by researchers from the Institute of Botany, Czech Academy of Sciences. Alcobiosis is a novel term describing the coexistence of algae and corticioid basidiomycetes, which are widespread in temperate woods. Scientific Reports has published their study.

The study’s lead author, Jan Vondrák of the Institute of Botany’s Department of Taxonomy, explains that when some of the fungal coatings on wood or bark (known as corticioid fungus) are disturbed, they would often be surprised to discover a layer of green algae. Because the fungus does not rely on the algae for nutrition, they learned that this is a symbiotic relationship of fungi and algae rather than a lichen.

The letters from the three terms, algae, corticioid fungus, and symbiosis, are combined to form the new name “alcobiosis” that the researchers have coined for this kind of coexisting.

The study team collected several samples over the course of several years and sequenced the DNA of the fungal and algal partners. They found that the symbiosis is quite prevalent and may be found in a wide variety of corticioid fungus within the class of agaricomycetes. A particular algal species among a variety of algae documented in diverse alcobioses is typically faithfully matched by a single fungus species.

Algal activity in alcobioses was monitored physiologically, and the results showed that the algae are alive, active, and highly involved in photosynthesis, which demonstrates that they thrive inside fungal tissue. Alcobioses resemble lichens in appearance, but they vary from them in that the fungal partner does not rely on the alga for nutrition.

The fundamental question that remains is how this symbiosis benefits each of the partners. The discovery also raises a number of issues about the geographic, ecological, and taxonomic aspects of the symbiosis, such as whether the variety of alcobioses rises from arctic to tropical locations.

This coexistence has already been discussed in articles. The majority of the time, however, these were only vague remarks stating that some corticioid fungus species frequently coexist with algae. This research  was the first to recognize alcobioses as a widespread phenomenon involving several fungus and algae.

The researchers also found that tiny gastropods, which frequently consume corticioid fungi, contribute to the spread of alcobioses. Their excretions include living algae and fungal cells, which quickly produce fresh alcobiotic covering. This form of reproduction resembles lichen “isidia.”

The Institute of Botany’s scientists have described a symbiotic connection that is fairly prevalent in Europe but has received little attention up to this point. As alcobioses are readily apparent to the unaided eye and can be easily distinguished from related fungi that do not establish this sort of interaction, a new area has opened up for the further research of alcobioses from numerous points of view by both professional biologists and biology amateurs.

Sources:

Jan Vondrák et al, Alcobiosis, an algal-fungal association on the threshold of lichenisation, Scientific Reports (2023). DOI: 10.1038/s41598-023-29384-4. www.nature.com/articles/s41598-023-29384-4

https://phys.org/news/2023-02-coexistence-algae-fungi.html

Scientists at Scripps Research have developed a new technique for studying mitochondria


The “powerhouses” of cells called mitochondria can now be studied in a new way thanks to an innovative imaging-based technique developed by scientists at Scripps Research.

The researchers reported their methods in the Journal of Cell Biology on February 14, 2023. These methods allow for the imaging and quantification of even subtle transformation inside mitochondria, and the linkage of these changes with other processes occurring in cellular environments.

In addition to producing energy, mitochondria are engaged in other vital cellular processes like cell division and survival in the face of diverse stresses. Researchers are keen to create treatments that might cure mitochondrial dysfunctions, which have been reported in a variety of disorders including Alzheimer’s, Parkinson’s, and other malignancies. Yet, until recently, scientific methods for analyzing mitochondria structure were inadequate.

Assistant professor of Integrative Structural and Computational Biology at Scripps Research and senior author of the study Danielle Grotjahn, PhD said that they now have a highly sophisticated toolkit for detecting and quantifying structural, and thus functional, differences in mitochondria—for example, in diseased versus healthy states.

Benjamin Barad, PhD, a postdoctoral research associate in the Grotjahn lab, and Michaela Medina, a PhD candidate in the lab, are the co-first authors of the research.

Mitochondria are a type of membrane-bound molecular machine found inside the cells of plants and animals. Mitochondria are tiny organelles found in every cell that perform essential biochemical operations and have their own small genomes and unique structure, including an outer membrane and a wavy inner membrane. The appearance of mitochondrial structures can undergo dramatic changes, as scientists have discovered, depending on the mitochondrion’s function or the stressors faced by the cell. There hasn’t been a reliable way to identify and quantify these structural alterations, despite their potential utility as markers of cell circumstances.

Cryo-electron tomography (cryo-ET) is a type of microscopy that captures three-dimensional images of biological material by focusing beams of electrons on them rather than light. Grotjahn’s team developed a computer toolbox to interpret imaging data from this method. This surface morphometrics toolset developed by the researchers allows for precise mapping and measuring of individual mitochondrial structures. Inner membrane bends and intermembrane spaces may provide clues to crucial mitochondrial and cellular processes.

According to Barad, this method basically allows them to transfer the beautiful 3-D images of mitochondria they can get through cryo-ET into sensitive, quantitative measures, which might be used to determine the specific causes of illnesses.

This toolset was proved by the group’s ability to map mitochondrial structural features in response to endoplasmic reticulum stress, a form of cellular stress frequently observed in neurodegenerative disorders. They saw measurable changes in core structural elements like the curvature of the inner membrane and the minimum distance between the inner and outside membranes when subjected to this stress.

The Grotjahn lab has shown proof-of-principle for their new toolset and will use it to investigate the mitochrondrial response to cellular stressors such as those caused by pathogens, toxins, and medication.

For instance, as Medina puts it, they may compare the effects on mitochondria in cells treated with a medication to the effects on mitochondria in untreated cells  Also, this method is not restricted to studying mitochondria; it can be applied to the investigation of various organelles within cells.

By Kelvinsong; modified by Sowlos – Own work based on: Mitochondrion mini.svg, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27731882

Sources:

Barad, B. A., Medina, M., Fuentes, D., Wiseman, R. L., & Grotjahn, D. A. (2023). Quantifying organellar ultrastructure in cryo-electron tomography using a surface morphometrics pipeline. The Journal of cell biology, 222 (4), e202204093. https://doi.org/10.1083/jcb.202204093

https://www.scripps.edu/news-and-events/press-room/2023/20230215-grotjahn-mitochondria.html

Centipedes don’t have eyes, so how do they find the light?


By Yasunori Koide – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=16029927

Scientists from Northeast Forestry University and the Zhejiang University School of Medicine collaborated to determine how the Chinese red-headed centipede detects light without the need of eyes or photoreceptors.

The group explains its experiments with the myriapods to determine how they detect sunlight in a report published in Proceedings of the National Academy of Sciences.

The venomous Chinese red-headed centipede has a long, black segmented body, yellow legs, and a big, eyeless head with long antennae and a mouth that may bite and inject venom into prey, predators, and humans who walk on them.

It is unclear from the existing literature whether the centipede avoids the sun to evade predators or to keep from overheating. Previous studies have demonstrated that the pencil-size bugs not only do not have eyes, but also lack the photoreceptors that would allow them to detect when sunlight is present.

The scientists ran various tests in which they placed specimens in transparent containers, some of which had black tape over them. How the centipedes behaved under different lighting conditions was then investigated. They also employed thermal cameras to monitor how sun exposure affected core body temperature. When exposed to sunlight, they observed that the antennae’s temperature increased rapidly. The readings revealed a 9 degrees Celsius rise in temperature in a matter of seconds.

Covering the centipedes’ curly red, segmented structures and re-testing the bugs to see how they react to unexpected flashes of light confirmed that the antennae were alerting the insects to sunlight. Due to the protection, the creatures were much less sensitive to light.

Antennae were examined further to determine their role as solar heat sensors, and the presence of thermal receptors termed BRTNaC1 ion channels was confirmed. The rise in temperature was what set them off.

Sources:

Zhihao Yao et al, A thermal receptor for non-visual sunlight detection in myriapods, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2218948120

https://phys.org/news/2023-02-eyeless-centipedes-sunlight.html

A range-shifting damselfly species is now cohabitating alongside its UK relative


By Darkone (talk · contribs) – Own work, CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=818299

New research demonstrates that an introduced European species of damselfly offers only a little threat to native British damselflies and dragonflies.

The little red-eyed damselfly has expanded its range northward from the Mediterranean as temperatures rise. In 1999, it was first seen in the UK, and since then it has spread throughout the country.

The new research examined data from the British Dragonfly Society to determine whether or not this has led to a decrease in native damselflies and dragonflies in the UK. This article is in the latest issue of Insect Conservation and Diversity.

The little red-eyed damselfly was found to have increased or maintained its population in regions where native dragonflies and damselflies were already present.

However, further research is required to determine the extent of the impact on two species of damselflies.

With range-shifting globally growing, researchers need to understand what influence newly arrived species have on ecosystems according to Dr. Regan Early, of the Centre for Ecology and Conservation at Exeter’s Penryn Campus in Cornwall.

Small red-eyed damselflies appear to have successfully established a population in the UK without negatively affecting native populations. It may be doing well in locations with favorable environments, and in the future, these biologically rich areas may be crucial for the expansion of range-expanding species.

Dr. Early differentiated between invading species and range-shifters, the latter of which come naturally from neighboring places. Existing native species have usually come into contact with range-shifters before, as these species have evolved in comparable habitats.

Human-transported invasive species can introduce harmful behaviors and illnesses to local ecosystems (e.g., gray squirrels in the UK).

This new study analyzed data from the British Dragonfly Society’s database of over 50,000 site visits between 2000 and 2015 to identify the locations where each of 17 native UK dragonflies and damselflies was sighted during those years. The impact of the introduction of little red-eyed damselflies on these native species was then evaluated by the research team.

Dr. Jamie Cranston, also from the University of Exeter, explained that their technique permits fast evaluation of how range-shifters are harming local animals. It demonstrates the power of citizen research, in this case by serving as a ‘early warning system’ for potential risks to UK species.

Two other species of damselfly have declined in areas where little red-eyed damselflies have become established, and one of them is closely related to the newcomer. Dr. Early hypothesizes that the little red-eyed damselfly might out-compete its sister species because of their shared habitat preferences and flying season.

However, due to their varied diet, damselflies shouldn’t face much competition for food unless there are significant shortages. In addition, there may be “empty niches” for new arrivals to exploit because the UK has a smaller diversity of these species than the rest of Europe.

Sources:

Cranston, J., Isaac, N.J.B. & Early, R. (2023) Associations between a range-shifting damselfly (Erythromma viridulum) and the UK’s resident Odonata suggest habitat sharing is more important than antagonism. Insect Conservation and Diversity, 1– 11. Available from: https://doi.org/10.1111/icad.12630

https://phys.org/news/2023-02-damselfly-species-habitat-uk-natives.html

Scientists have found out how electrochemical energy in bacteria makes them resistant to antibiotics


By Dr Graham Beards at en.wikipedia, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=25206097

The threat posed by antibiotic-resistant microorganisms to world health is growing. Each year, millions of people die as a result of bacterial infections that acquire genetic resistance to antibiotics. However, one of the many ways that bacteria might resist antibiotics is through genetic resistance.

Texas A&M University researchers are looking at how bacteria might become resistant to drugs without gaining new genes or changing their already existing ones. To comprehend how bacteria adapt to antibiotics, the researches focused on differences in the electrochemical energy that drive bacterial development. These energies are powerful: The electric field that contributes to them can be greater in a single bacteria than in a lightning bolts.

In order to live in harsh environments, bacteria have evolved a variety of adaption tactics over billions of years, according to Dr. Pushkar Lele, an associate professor in Texas A&M’s Artie McFerrin Department of Chemical Engineering. The majority of adaptive processes are still poorly known.

The team’s research was published in a paper titled “Heterogeneous Distribution of Proton-Motive Force in Nonheritable Antibiotic Resistance” in the journal mBio.

Eight times as much antibiotics are needed annually to keep animals healthy for human consumption as compared to the 3 million pounds used annually in human treatment. Unfortunately, overuse and careless application of antibiotics can foster an environment that encourages the growth of bacterial antibiotic resistance.

Individual bacterial cells with insufficient energy commonly withstand deadly dosages of antibiotics, according to earlier investigations. It’s possible that these inactive cells lack the genes necessary to develop antibiotic resistance. They instead sleep throughout the antibiotic treatment.

Antibiotics destroy bacteria that are actively developing, often by targeting on important cellular functions, according to Lele. High energy levels, in fact, are thought to be harmful to their chances of survival in dormant bacteria since those activities may be halted there, rendering antibiotics useless.

Therefore, the team was shocked when they saw Escherichia coli survivors swimming fast for several hours in the presence of antibiotics. Flagella, which are revolving, thin appendages, are used by bacteria to swim. Strong electric fields that are applied across the cell membrane cause the flagella to rotate several hundred times per second. Thus, the studies revealed that survivors maintain high electrochemical energy, which goes against what is often believed.

The researchers gave cells several antibiotic combinations in order to examine the relationship between cell energy and antibiotic tolerance. They kept track of the electrochemical energy levels in the surviving cells using fluorescent dyes and sensitive photon detection methods. The cells were in a growth arrest yet unexpectedly showed a great range of energies.

The next step was to predict how the survivors would react if the antibiotic treatment was interrupted. Working at the level of a single cell, they found that high energy cells grew right away when the antibiotic threat was removed, highlighting the dangers of partial antibiotic treatments.

The finding suggest that certain bacteria, even those that are neither resistant nor dormant, can survive the antibiotic treatment. The capacity of these bacteria to swim out of dangerous areas and spread quickly is alarming. Additionally, they are able to respond differently to the antibiotics due to their high energy retention.

According to Lele, the energy source in E. coli that fuels motility also powers numerous transporters, commonly referred to as efflux pumps. The swimming cells they saw may have evolved via this method, as these transporters may pump antibiotics out of the cell to decrease the toxicity.

If an infected patient doesn’t improve after receiving a first antibiotic intervention, medical therapy frequently requires changing to a new antibiotic. The intriguing finding, in Lele’s opinion, is that cells with high energy survive more frequently when antibiotics are changed than when only one antibiotic is used.

In spite of sharing the same genetic makeup, cells in a population may and do use a variety of ways to adapt to antibiotic stress, according to Lele’s research. If treatment plans took into consideration this variation, the results would be better.

Sources:

Lee, A. H., Gupta, R., Nguyen, H. N., Schmitz, I. R., Siegele, D. A., & Lele, P. P. (2023). Heterogeneous Distribution of Proton Motive Force in Nonheritable Antibiotic Resistance. mBio, e0238422. Advance online publication. https://doi.org/10.1128/mbio.02384-22

https://phys.org/news/2023-02-reveal-bacterial-electrochemical-energy-powers.html

A study of zebrafish has contributed to the understanding of the causes of scoliosis


https://elifesciences.org/articles/83883

Researchers at the University of Oregon have made important discoveries into the genetics of scoliosis, an abnormal curvature of the spine.

UO biology professor Dan Grimes and his team of researchers have discovered two small proteins that play an important role in maintaining spinal alignment during critical stages of development. When these proteins are mutated in zebrafish, the fish develop deformed spines similar to those of people with scoliosis.

Research was published by the group on December 1 in the journal eLife. The laboratory where Dr. Grimes works is situated in the Department of Biology of the College of Arts and Sciences at the University of Oregon.

Idiopathic scoliosis is the form of the disorder that does not have a known cause, and it often appears in adolescents, often at a period of rapid growth. Still, there is a great deal about scoliosis that scientists don’t yet know.

It has been challenging to investigate spinal curvature in the lab because of the unique stresses placed on the spine by humans’ bipedal posture that are not experienced by four-legged lab animals such as mice and rats.

However, while working as a postdoctoral researcher, Grimes noticed zebrafish with curled spines. Grimes speculated that the thrusting motion of the fish through the water might be more analogous to the pressures experienced by the human spine.

Upon additional investigation, he discovered that cerebrospinal fluid is pushed forward by microscopic hairs called cilia that wave down the spine. Maintaining a straight back required constant, smooth movement along the spine. Fish whose mutations affected their cilia and, by extension, their ability to swim fluidly, developed spines that were curled.

The next logical step in the process is laid out in this recently published study. The group revealed that zebrafish with mutations in two different proteins developed a curved spine similar to that of people with scoliosis.

Spinal neurons produce the two small proteins. The cilia in the body’s spinal cord are responsible for turning on their production. The researchers hypothesize that once these proteins are released by the neurons, they bind to receptors in the muscles surrounding the spine, potentially altering the way in which these muscles support the spine.

At specific stages of development, the proteins appear to play an especially important role. Some of the studies involved fish that were particularly vulnerable to changes in temperature. They found that they could switch genes on and off at will by manipulating the tank’s water temperature.

Big spine curvature, Grimes explained, are the result of interference throughout the “adolescent” years. In humans, scoliosis often develops throughout adolescence, and this finding supports the idea that the route is active during this time of rapid growth.

The next step in the team’s quest to discover the root causes of scoliosis is to investigate what occurs farther along this pathway.

Graduate student Zoe Irons said that it is a kind of a mystery how the protein itself gets it to the receptor.

The results can also contribute to scientists’ overall knowledge of animal structure and function.

How small molecular processes give rise to huge anatomical structures is a topic of intense study at Grimes’s group. Since it involves coordinated activity from nerve cells, skeletal muscle, and bone, it serves as a useful analogy.

Sources:

Elizabeth A Bearce, Zoe H Irons, Johnathan R O’Hara-Smith, Colin J Kuhns, Sophie I Fisher, William E Crow, Daniel T Grimes (2022) Urotensin II-related peptides, Urp1 and Urp2, control zebrafish spine morphology eLife 11:e83883. https://doi.org/10.7554/eLife.83883

https://phys.org/news/2023-02-zebrafish-reveal-scoliosis.html

Scientists learn about the wide variety of viroids and viroid-like entities


green flat oblong leaf plant on close up photography
Photo by Pixabay on Pexels.com

To recognize and understand viroids and viroid-like covalently closed circular RNAs, a team of researchers from the National Library of Medicine (NLM) and partnering university research institutes have created a computer pipeline. Compared to linear RNA, this kind of single-stranded RNA forms a continuous, covalently closed circle. The journal Cell reported the findings.

Viroids are the smallest and most basic known infectious agents. They are circular RNAs with just 250–400 nucleotides. They had been thought to solely infect plants, up until now. The lack of knowledge about the diversity of viroid and viroid-like RNAs encouraged researchers to learn more about these sub-viral agents and their potential prevalence in various environments and hosts.

Researchers discovered 11,378 viroid-like cccRNAs spanning 4,409 species-level clusters by examining a collection of 5,131 metatranscriptomes and 1,344 plant transcriptomes. Comparing this discovery to the previously reported viroid-like elements, there was a five-fold increase.

Researchers found that this unique family of pathogens is widespread in all sorts of habitats and hosts, similar to the more well-known RNA viruses, and is not restricted in its spread to a few plants as was initially assumed. Additionally, completely unknown viral types were discovered, and distant relatives of the human Hepatitis Delta Virus (Hepatitis D) were found, providing insight into the origin of this important human illness.

Eugene V. Koonin, Ph.D., a co-author of the paper and a senior investigator in the Computational Biology Branch of NLM’s Intramural Research Program, stated that this work opens up new paths for researchers worldwide.  He said they are working on some follow-up investigations.

Sources:

Benjamin D. Lee et al. (2023). Mining metatranscriptomes reveals a vast world of viroid-like circular RNAs, Cell. DOI: 10.1016/j.cell.2022.12.039

https://phys.org/news/2023-01-uncover-diversity-viroids-viroid-like-agents.html

The development of artificial human skin offers the path for new treatments for skin cancer


By Juliana Casagrande Tavoloni Braga, Mariana Petaccia Macedo, Clovis Pinto, João Duprat, MariaDirlei Begnami, Giovanni Pellacani, Gisele Gargantini Rezze – (2013). “Learning Reflectance Confocal Microscopy of Melanocytic Skin Lesions through Histopathologic Transversal Sections”. PLoS ONE 8 (12): e81205. DOI:10.1371/journal.pone.0081205. ISSN 1932-6203.-“This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.”, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=87004389

A study team from the University of Copenhagen was able to stop invasive development in a skin cancer model by utilizing artificial human skin.

The study, which examines what exactly occurs when a cell transforms into a cancer cell, has been published in Science Signaling.

The researchers have been investigating the so-called TGF beta pathway, one of the cell’s signaling mechanisms. This pathway, which regulates things like cell proliferation and cell division, is essential for the communication between the cell and its environment. The cell may develop into a cancer cell and invade the surrounding tissue if these systems are compromised according to Professor and Team Lead Hans Wandall from the University of Copenhagen’s Department of Cellular and Molecular Medicine.

Your skin cells won’t just randomly begin to infiltrate the hypo-dermis and cause havoc under normal conditions. They will instead create a fresh layer of skin. However, when cancerous cells appear, the skin’s layers’ boundaries are no longer respected, and the cells begin to invade one another. This type of growth is invasive.

In their research on the TGF beta pathway, Hans Wandall and his colleagues developed strategies for preventing invasive development, which helped to reduce the invasive growth of skin cancer.

Drugs that can disrupt these signaling pathways are currently available, and they might be tested. In this study, they have employed several of them said Sally Dabelsteen, an associate professor and co-author of the study from the School of Dentistry.

Dr. Zilu Ye and Professor Jesper V. Olsen from the Faculty of Health and Medical Sciences’ Novo Nordisk Foundation Center for Protein Research collaborated with Hans Wandall and Sally Dabelsteen on this project.

Some of these medications have previously undergone testing on humans, while others are now undergoing testing in relation to several other cancers. Additionally, they might be examined especially for skin cancer.

Human skin cells that have been genetically altered are employed as the artificial skin in this latest study. On collagen-rich subcutaneous tissue, skin cells are generated. The cells proliferate in layers as a result, exactly like the skin of a human body.

The skin model, also known as artificial skin, enables researchers to introduce artificial genetic modifications very fast, which gives insight into the processes that promote skin growth and regeneration. This is in contrast to mouse models.

In this method, not just skin cancer but also other skin conditions may be reproduced and their progression can be tracked.

The researchers have overcome the potentially problematic question of whether the outcomes of experiments on mouse models can be translated to human tissue by employing fake human skin. Most of these research were conducted in the past using mice as models. Instead, because the artificial skin brings us closer to the reality of humans, the researchers can now draw the conclusion that these compounds likely are not dangerous and might be used in practice.

The researchers’ synthetic skin is similar to the skin used to test cosmetics in the European Union, which outlawed animal testing in 2004. Hans Wandall notes that using artificial skin does not enable scientists to examine a drug’s impact on a complete organism. Since the middle of the 1980s, cosmetics businesses have employed skin models similar to the one presented here.

The researchers may examine the effect focusing on the specific organ—the skin—and then they earn experiences with regard to how chemicals work, while they strive to discover whether it can harm the structure of the skin and the healthy skin cells.

Sources:

Zilu Ye et al. (2022). Characterization of TGF-β signaling in a human organotypic skin model reveals that loss of TGF-βRII induces invasive tissue growth, Science Signaling (2022) DOI: 10.1126/scisignal.abo2206

https://phys.org/news/2023-01-artificial-human-skin-paves-cancer.html