Threatened grey-necked rockfowl's habitat even smaller than expected, study finds

Researchers’ findings may help drive conservation efforts for this unique bird species, found only in Central Africa

Peer-Reviewed Publication

SAN DIEGO ZOO WILDLIFE ALLIANCE

SAN DIEGO (AUG. 10, 2023) — A new study on gray-necked rockfowl has found a much smaller range of suitable habitat for this elusive African bird than was previously assumed, and may warrant a downgrade in its conservation status.

Scientists from the Cameroon Biodiversity Association (CAMBIO) in Cameroon, in partnership with San Diego Zoo Wildlife Alliance, set out to better understand how much suitable habitat remains for the rockfowl, and where the birds can still be found.

Understanding suitable habitat and its extent is crucial for protecting species. However, scientists have limited knowledge about the available habitat for many species, including the grey-necked rockfowl (Picathartes oreas). One of only two species in the little-known family Picathartidae, grey-necked rockfowl are found only in the forests of Central Africa. Changes in land use are resulting in disappearing forests and habitat fragmentation in this region.

The study, published in Bird Conservation International, utilized intensive field work and advanced modeling techniques to generate crucial insights, including evidence to suggest changing the species’ status on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, from Near Threatened to Vulnerable.

Scientists assessed 339 new and historical grey-necked rockfowl occurrence records, along with environmental variables. Then they predicted suitable habitat available for grey-necked rockfowl, and where conservation efforts for the species should be focused. The results show that the birds are strongly connected to areas with steep slopes and abundant forest cover, while variables related to climate, vegetation health and habitat condition didn't play a role in the birds’ distribution.

This study did not consider, however, how predictor variables might change in the future, due to factors such as climate change.

“Forest cover loss across Central Africa, home to many endemic, endangered and often understudied species, is accentuating biodiversity loss driven by climate change and other pressures,” said Ekwoge Abwe, Ph.D., a Scientific Program Manager for San Diego Zoo Wildlife Alliance, manager of CAMBIO and a co-author of the study. “Given its specific habitat requirements, including forest cover and steep slopes, the persistence of grey-necked Picathartes could be a good indicator of healthy forest. Conserving these unique habitats will help not only these birds, but a wide range of other related species.”

Ultimately, the team identified around 6,690 square miles, or 17,327 square kilometers, that fit the species’ desired criteria.

“Unfortunately, only about 2,490 square kilometers (961 square miles, or 14.4%) of this suitable habitat is in protected areas with strictly enforced conservation efforts,” said Guilain Tsetagho, research assistant at CAMBIO, who led the study. “Considering the bird’s limited range, specific nesting habitat needs and the increasing pressures from human activities, changing its conservation status could help prevent further land use from damaging rockfowl-compatible areas.”

 

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About San Diego Zoo Wildlife Alliance

San Diego Zoo Wildlife Alliance, a nonprofit conservation leader, inspires passion for nature and collaboration for a healthier world. The Alliance supports innovative conservation science through global partnerships. Through wildlife care, science expertise and collaboration, more than 44 endangered species have been reintroduced to native habitats. Annually, the Alliance reaches over 1 billion people, in person at the San Diego Zoo and San Diego Zoo Safari Park, and virtually in 150 countries through media channels, including San Diego Zoo Wildlife Explorers television programming in children’s hospitals in 13 countries. Wildlife Allies—members, donors and guests—make success possible.

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JOURNAL

Bird Conservation International

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Modeling the potential distribution of the threatened Grey-necked Picathartes Picathartes oreas across its entire range

 

Hidden moles in hidden holes

Peer-Reviewed Publication

UNIVERSITY OF PLYMOUTH

 

IMAGE: TALPA HAKKARIENSIS – FOUND IN THE HAKKARI REGION OF SOUTHEASTERN TURKEY – WAS IDENTIFIED AS A NEW SPECIES OF MOLE, HIGHLY DISTINCTIVE IN TERMS OF BOTH ITS MORPHOLOGY AND DNA view more 

CREDIT: UNIVERSITY OF PLYMOUTH

Scientists have identified two types of mole which they believe have been living undiscovered in the mountains of eastern Turkey for as many as 3 million years.

The new moles – named Talpa hakkariensis and Talpa davidiana tatvanensis – belong to a familiar group of subterranean, invertebrate-eating mammals found across Europe and Western Asia.

While only one species, Talpa europaea, is found in Britain, further east there are a number of different moles, many of which have very small geographical ranges.

The researchers – using cutting edge DNA technology – have confirmed the new forms are biologically distinct from others in the group.

Both inhabit mountainous regions in eastern Turkey, and are able to survive in temperatures of up to 50°C in summer and being buried under two metres of snow in winter.

The study, published in the Zoological Journal of the Linnean Society, was conducted by researchers from Ondokuz Mayıs University (Turkey), Indiana University (USA), and the University of Plymouth (UK).

Senior author David Bilton, Professor of Aquatic Biology at the University of Plymouth, has previously been responsible for identifying almost 80 new species of animals, particularly insects, and said the new discoveries were notable for a number of reasons.

“It is very rare to find new species of mammals today,” he said. “There are only around 6,500 mammal species that have been identified across the world and, by comparison, there are around 400,000 species of beetles known, with an estimated 1-2 million on Earth. Superficially, the new moles we have identified in this study appear similar to other species, since living underground imposes serious constraints on the evolution of body size and shape – there are a limited number of options available for moles really. Our study highlights how, in such circumstances, we can under-estimate the true nature of biodiversity, even in groups like mammals, where most people would assume we know all the species with which we share the planet.”

The discoveries mean that the number of known Eurasian moles has been raised from 16 to 18, and each have their own distinct genetic and physical characteristics.

To identify their latest finds, the researchers studied the size and shape of various bodily structures, using advanced mathematical analyses, which also allowed them to include specimens collected in the 19th century that are still available in museum collections.

A complimentary analysis of the moles’ DNA, and a detailed comparison with known species, then confirmed their distinctiveness.

As a result, Talpa hakkariensis – found in the Hakkari region of southeastern Turkey – was identified as a new species of mole, highly distinctive in terms of both its morphology and DNA.

Talpa davidiana tatvanensis – found near Bitlis, also in southeastern Turkey – was also identified as being morphologically distinct but has been classified as a subspecies of Talpa davidiana. First identified in 1884, T. davidiana it is listed as data deficient by the International Union for Conservation of Nature (IUCN).

Professor Bilton added: “We have no doubt that further investigations will reveal additional diversity, and that more new species of mole remain undiscovered in this and adjacent regions. Amid increasing calls to preserve global biodiversity, if we are looking to protect species we need to know they exist in the first place. Through this study, we have established something of a hidden pocket of biodiversity and know far more about the species that live within it than previously. That will be critical for conservation experts, and society as a whole, when considering how best to manage this part of the planet.”

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JOURNAL

Zoological Journal of the Linnean Society

DOI

10.1093/zoolinnean/zlad049 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Notes from the Anatolian underground: two new mole taxa from Eastern Turkey, together with a revised phylogeny of the genus Talpa (Mammalia: Eulipotyphla: Talpidae)

Karl Marx  

"We recognize our old friend, our old mole, who knows so well how to work underground, suddenly to appear: the revolution."

 

Researchers “film” novel catalyst at work

Catalysis scheme developed at the University of Bonn is inexpensive, sustainable, and effective

Peer-Reviewed Publication

UNIVERSITY OF BONN

 

IMAGE: PROF. DR. PETER VÖHRINGER, DR. LUIS DOMENIANNI, JONAS SCHMIDT AND PROF. DR. ANDREAS GANSÄUER. view more 

CREDIT: PHOTO: VOLKER LANNERT/UNIVERSITY OF BONN

A novel catalysis scheme enables chemical reactions that were previously virtually impossible. The method developed at the University of Bonn is also environmentally friendly and does not require rare and precious metals. The researchers recorded the exact course of the catalysis in a kind of high-speed film. They did this using special lasers that can make processes visible that last only fractions of a billionth of a second. The results allow them to further optimize the catalyst. They have been published in the international edition of the renowned journal Angewandte Chemie.

Let’s say you are playing mini golf. There is a small hill on the course that the golf ball has to overcome in order to roll into the hole behind it. To do this, you need to hit it with enough force. Otherwise, it will not make it over the obstacle, but will roll back towards you.

It is similar for many chemical reactions: In order for them to proceed, you first have to supply them with enough energy. A catalyst reduces this activation energy. To stay in the picture: It levels the hill a bit so the ball needs less momentum to roll over it. The reaction is therefore easier and faster. “Some reactions are even only made possible by the use of catalysts,” explains Prof. Dr. Andreas Gansäuer.

Titanium instead of precious metals

The researcher works at the Kekulé Institute of Organic Chemistry and Biochemistry at the University of Bonn. He has been working for years on how to simplify the production of certain carbon compounds. The use of catalysts is usually the means of choice here. The problem: Often, the “reaction accelerators” consist of rare and precious metals such as platinum, palladium, or iridium.

“We usually use titanium compounds instead,” says Gansäuer. “This is because titanium is one of the most abundant elements in the earth’s crust and is also completely non-toxic.” However, titanium-based catalysts often still need a companion to be able to accelerate chemical reactions. Most often, this is also a metal. It activates the catalyst, (unlike the latter) is consumed in the reaction, and generates by-products as waster.

“This is both costly and not very sustainable,” emphasizes Gansäuer’s colleague Prof. Dr. Peter Vöhringer of the Clausius Institute for Physical and Theoretical Chemistry at the University of Bonn. “However, there have been attempts for some time to achieve this activation in a different way: By irradiating the catalyst with light. We have now implemented this idea. At the same time we filmed, in a sense, the processes that occur during activation and catalysis.”

Lasers create “lightning storm”

The “high-speed camera” used by the researchers was a spectrometer - this is a complex instrument that can be used to determine what a molecule looks like at a certain point in time. For this to work, you also need a flash. To do this, the researchers use a laser that switches on and off continuously. The bright moments each last only a few hundred femtoseconds (a femtosecond is the millionth part of a billionth of a second). The catalysis process is thus broken down into a sequence of individual images. “This allows us to visualize ultrafast processes,” says Vöhringer, who is a specialist in this method.

Not all molecules can be filmed easily. “We therefore had to make some modifications to the titanium catalyst we usually use,” says Gansäuer. The experiments show that the compound can be activated by light and is then able to catalyze a specific form of redox reactions. In redox reactions, electrons are passed from one reactant to the other. “This process is facilitated by the activated catalyst,” Gansäuer explains. “This allows us, for example, to produce compounds that serve as starting materials for many important drugs.”

Greedy for electrons

The “high-speed film” documents exactly what happens during light activation. “Electrons resemble a compass needle that points in a certain direction,” says Jonas Schmidt, who is doing his doctorate in Prof. Vöhringer’s research group. “This spin changes as a result of irradiation.” Figuratively speaking, the titanium compound thus becomes “greedier” to accept an electron. When it does, it starts the redox reaction.

“Thanks to the insights we have gained with our method, we can now further optimize the catalyst,” explains Vöhringer, who, like Prof. Gansäuer, is a member of the Transdisciplinary Research Area “Matter” at the University of Bonn. It is already possible to use it to carry out chemical reactions that were hardly feasible before. The success is also an expression of fruitful cooperation between organic chemistry on the one hand and laser and molecular physics on the other, Vöhringer emphasizes: “Our study shows the fruits that can come from collaboration between two research groups with completely different methodological backgrounds.”

Funding:

The study was funded by the German Research Foundation (DFG) and the Manchot Foundation.

Publication: Jonas Schmidt, Luis I. Domenianni, Marcel Leuschner, Andreas Gansäuer und Peter Vöhringer: Observing the Entry Events of a Titanium-Based Photoredox Catalytic Cycle in Real Time; Angewandte Chemie; DOI: 10.1002/anie.202307178; Internet: https://onlinelibrary.wiley.com/doi/10.1002/anie.202307178

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JOURNAL

Angewandte Chemie

DOI

10.1002/anie.202307178 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Observing the Entry Events of a Titanium-Based Photoredox Catalytic Cycle in Real Time

 

Mosquito hearing could be targeted by insecticides

Peer-reviewed | observational study | animals

UNIVERSITY COLLEGE LONDON

Specific receptors in the ears of mosquitoes have been revealed to modulate their hearing,  finds a new study led by researchers at UCL and University of Oldenburg. Scientists say, this discovery could help develop new insecticides and control the spread of harmful diseases, such as malaria.

The ability of male mosquitoes to hear female mosquitoes is a crucial requirement for their reproduction. As a result, the finding could help develop novel insecticides or mating disruptors to prevent mosquito-borne diseases like malaria, dengue, and yellow fever

In the study, published in Nature Communications, the researchers focused on a signalling pathway involving a molecule called octopamine. They demonstrated that it is key for mosquito hearing and mating partner detection, and so is a potential new target for mosquito control.

Male mosquitoes acoustically detect the buzz generated by females within large swarms that form transiently at dusk.

As swarms are potentially noisy, mosquitoes have developed highly sophisticated ears to detect the faint flight tone of females amid hundreds of mosquitoes flying together.

However, the molecular mechanisms by which mosquito males ‘sharpen their ears’ to respond to female flight tones during swarm time have been largely unknown.

The researchers looked at the expression of genes in the mosquito ear and found that an octopamine receptor specifically peaks in the male mosquito ear when mosquitoes swarm.

The study found that octopamine affects mosquito hearing on multiple levels. It modulates the frequency tuning and stiffness of the sound receiver in the male ear, and also controls other mechanical changes to boost the detection of the female.

The researchers demonstrated that the octopaminergic system in the mosquito ear can be targeted by insecticides.

Mosquito mating is a bottleneck for mosquito survival, so identifying new targets to disrupt it is key to controlling disease-transmitting mosquito populations.

Co-lead author, Dr Marta Andrés (UCL Ear Institute) said: “Octopamine receptors are of particular interest as they are highlighy suitable for insecticide development. We plan to use these findings to develop novel molecules to develop mating disruptors for malaria mosquitoes.

“Because mosquito hearing is required for mosquito mating, it can be targeted to disrupt mosquito reproduction. And increased knowledge of mosquito auditory neurosciences could lead to the development of mosquito mating disruptors for mosquito control.”

Co-lead author, Professor Joerg Albert (UCL Ear Institute and University of Oldenburg) said: “The molecular and mechanistic complexity of mosquito hearing is truly remarkable. With the identification of an octopamine pathway we are just beginning to scratch the outer surface of the tip of an iceberg.

“Future studies will without doubt deliver deeper insights into how mosquito hearing works and also provide us with novel opportunities to control mosquito populations and reduce human disease.”

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-40029-y 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

. Hearing of malaria mosquitoes is modulated by a beta-adrenergic-like octopamine receptor which serves as insecticide target

 

USTC develops new catalysts for CO2 electroreduction

Peer-Reviewed Publication

UNIVERSITY OF SCIENCE AND TECHNOLOGY OF CHINA

 

IMAGE: ANALYSIS OF FINE STRUCTURE, PROPERTIES, AND CATALYTIC REACTION MECHANISM OF CATALYSTS view more 

CREDIT: IMAGE BY PROF. SONG’S TEAM

As a crucial part of Carbon Capture, Utilization, and Storage (CCUS) technology, CO2 reduction reaction (CO2RR) to carbon-based fuels and chemicals presents broad application prospects in renewable energy storage and CO2 negative emission. Recently, a team led by Prof. SONG Li and Associate Researcher HE Qun from the National Synchrotron Radiation Laboratory of the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) put forth a novel understanding of the mechanism of CO2RR on the nickel (Ni) single-atomic sites. Their study, titled "Asymmetric Dinitrogen-Coordinated Nickel Single-Atomic Sites for Efficient CO2 Electroreduction", was published in Nature Communications on 24 June.

An ideal CO2RR catalyst requires low overpotential and high current density to products. However, former catalysts either are featured with high cost and low current density, such as gold (Au) and silver (Ag), usually exhibit much higher overpotentials than Au and Ag, such as Fe, Co, or Ni, limiting reaction efficiency. Therefore, it is imperative to develop overpotential low, high current density, abundant 3d metal-based catalysts to replace precious metal catalysts for CO2RR. To address those challenges, the researchers proposed an asymmetric dinitrogen-coordinated nickel single-atom catalyst (Ni-N-C). By utilizing the unsaturated and asymmetric characteristics of the sites, structural self-optimization during the electrochemical process is achieved, thereby enhancing the intrinsic activity of the sites in CO2RR.

In the study, the team designed and synthesized Ni-N-C featuring dinitrogen coordination (pyridinic and pyrrolic nitrogen) and then utilized it for CO2 electroreduction reactions in neutral and alkaline media. Synchrotron radiation X-ray absorption spectra and emission spectra revealed the local coordination structure of Ni sites in the catalyst. The electrochemical test results showed that the Ni-N-C catalyst could achieve very high electrochemical performance in both neutral (H-type cell) and alkaline (gas diffusion electrode, GDE) electrolytes. Especially in alkaline conditions, the catalyst could achieve a CO partial current density of 20.1 mA cmgeo-2 at -0.15 V vs. reversible hydrogen electrode (VRHE), Faraday efficiency of over 90% for CO in the potential range of -0.15 to -0.9 VRHE, and high turnover frequency (TOF) of over 274,000 site-1 h-1 at -1.0 VRHE, surpassing most reported catalysts.

This study offers a novel comprehension of the catalyst's role in the CO2 electroreduction reaction and promises to shed new light on future CO2 reduction technologies.

 

Jane FAN Qiong 

Tel: +86-551-63607280 

E-mail:englishnews@ustc.edu.cn

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-39505-2 

ARTICLE TITLE

Asymmetric dinitrogen-coordinated nickel single-atomic sites for efficient CO2 electroreduction

 

Pivotal discovery in sensor technology to combat water contamination and more

New screening method eliminates faulty electronic sensors for measuring toxins and other elements in water

Peer-Reviewed Publication

DOE/ARGONNE NATIONAL LABORATORY

There is a global water crisis, and it is not only about the dwindling supply of clean water. Contaminated drinking water exposes hundreds of millions of people worldwide to toxins, such as bacteria, heavy metals, pesticides and coronaviruses. This contamination imperils public health and can cause serious illnesses.

A team of researchers from the U.S. Department of Energy’s Argonne National Laboratory, along with the Pritzker School of Molecular Engineering at the University of Chicago and the University of Wisconsin — Milwaukee, has devised a pathway for the mass manufacture of sensors able to simultaneously detect lead, mercury and E. coli. in flowing tap water. The team’s innovation promises to help safeguard public health by providing early warning for contamination.

“Traditionally, sensors designed to measure contaminants in water have suffered from reliability issues and the inability to detect faulty devices,” said Argonne scientist Haihui Pu, who holds a joint appointment with UChicago’s Pritzker Molecular Engineering. “Improved sensors could avert health crises.”

At the core of these sensors lies a one-nanometer-thick layer of carbon and oxygen atoms, a form of graphene, which is coated on a silicon substrate. This graphene material serves a similar purpose to the semiconductors found in computer chips. Gold electrodes are then imprinted onto the graphene surface, followed by a nanometer-thick insulating layer of aluminum oxide. Each sensor is tailored to detect one of the three toxins: lead, mercury or E. coli.

One of the major challenges in mass manufacturing these sensors has been assessing their quality. Tiny areas of undesired porosity can form in the ultra-thin insulating layer. This porosity allows electrons from the bottom graphene layer to escape into the top insulating layer. This leakage compromises its effectiveness as an insulator and results in unreliable sensor responses.

The team's recent publication in Nature Communications describes a screening method to identify defective devices before mass production. The method involves measuring the electrical response of the insulating layer while the sensor is submerged in water. Key is that the screening does not damage the sensor. By employing this technique, the team identified structural defects in the insulating layers. They were then able to establish criteria to easily detect faulty devices.

To demonstrate the efficacy of their approach, the team evaluated a three-sensor array able to simultaneously detect lead, mercury and E. coli in flowing tap water. Using machine learning algorithms to analyze the results, they were able to quantify toxin levels down to the parts per billion, even in the presence of interfering elements.

“The beauty of the sensors is that you can apply them in any form of water, not just tap water,” said Junhong Chen, Argonne’s lead water strategist and Crown Family Professor at Pritzker Molecular Engineering. “What’s more, you can combine three, thirty or three hundred sensors, with each tailored to detect different constituents.” These include not only heavy metals and bacteria, but pharmaceuticals, pesticides, coronaviruses and a common contaminant in water, per- and polyfluoroalkyl substances. They might also include critical resources, such as cobalt for batteries and nitrogen and phosphorus as nutrients for plants and animals.

Once problematic or valuable elements are identified and removed, the sensors can be used to assess the cleanliness of treated water. The results can guide the safe reuse of the water, including potable use, agriculture and irrigation, groundwater replenishment and industrial processes.

Chen expressed hope for commercializing this technology through a startup company he founded. “But water contamination poses a global health problem demanding collective efforts,” he said.

The team’s screening method offers a versatile tool for monitoring water quality and optimizing its safe reuse. As scientists tackle this critical issue, their efforts serve as a beacon of hope for a healthier, more sustainable future.

This research appeared in Nature Communications. Contributors from Argonne and UChicago’s Pritzker School of Molecular Engineering include Pu, Chen and Xiaoyu Sui. Contributors from the University of Wisconsin-Milwaukee are Arnab Maity, Jingbo Chang, Kai Bottum, Bing Jin, Guihua Zhou, Yale Wang and Ganhua Lu.

This research received support from the Laboratory Directed Research and Development program at Argonne and the National Science Foundation.

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-39701-0 

ARTICLE TITLE

Scalable graphene sensor array for real-time toxins monitoring in flowing water

 

Novel information on the neural origins of speech and singing

Peer-Reviewed Publication

UNIVERSITY OF HELSINKI

Unlike previously thought, speech production and singing are supported by the same circuitry in the brain. Observations in a new study can help develop increasingly effective rehabilitation methods for patients with aphasia.

The neural network related to speech is mostly located in the left cerebral hemisphere, while singing has been primarily associated with the structures of both hemispheres. However, a new study indicates that the left hemisphere has a greater significance, including in terms of singing, than previously thought.

“According to a notion prevalent for more than 50 years, the potential preservation of singing ability in aphasia is based on the fact that the right hemisphere of the brain offers, as it were, a detour to expressing sung words,” says Doctoral Researcher Anni Pitkäniemi from the University of Helsinki.

This theory has also served as a basis for the development of singing-based rehabilitation strategies for patients with aphasia, or difficulty producing speech due to cerebrovascular disease.

However, a recently published study carried out by the Cognitive Brain Research Unit at the University of Helsinki found that, contrary to the researchers’ expectations, the ability to produce words by singing was associated not with the structures of the right hemisphere, but, as with speech, with the language network of the left hemisphere.

Both shared and distinct neural connections

Another key finding in the study was that, while the results indicate that the production of speech and singing are centrally linked to the language network of the brain, they are partially dispersed into distinct circuits under that network.

In fact, it was found that the production of sung words was linked to a specific part of the language network, the ventral stream associated with understanding speech.

In contrast, fluent speech was connected in patients with aphasia not only with what is known as the dorsal stream of the left hemisphere, associated with speech production, but also with other connections. These include the above-mentioned ventral stream as well as pathways entirely outside the language network, which are more commonly associated with information processing and motor functions in the brain.

“The scale of the network demonstrates the complexity of conversation-level speech,” Pitkäniemi points out.

“The observation also now explains why the ability to produce familiar lyrics is preserved only in certain patients,” she adds. The extent of damage within the language network, she further remarks, has the largest effect on this.

According to Pitkäniemi, the structures of the right hemisphere considered central to singing are likely to play a more important role in other significant factors associated with singing, including the production of melody and rhythm.

Towards increasingly personalised rehabilitation

For centuries, researchers have been interested in the relationship between music and language.

“There are cases in research literature dating back to the eighteenth century of persons with stroke losing their ability to speak due to aphasia, while unexpectedly retaining the ability to sing the words of familiar songs fluently,” Pitkäniemi says.

Next, the researchers at the University of Helsinki intend to investigate which brain networks are connected, for example, to learning new songs or producing melody and rhythm. The goal is to find methods based on singing for rehabilitating people with aphasia, which could be applied in an increasingly personalised and effective manner. 

“The findings of the recently published study can already help define biological markers that could be useful, for example, in assessing the effectiveness of treatment or rehabilitation,” Pitkäniemi muses.

“The findings also provide indications of the at least partly parallel development of speech and singing, which is interesting from the perspective of evolutionary neuroscience,” she adds.

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JOURNAL

Communications Biology

DOI

10.1038/s42003-023-05152-y 

ARTICLE TITLE

Hodological organization of spoken language production and singing in the human brain

Researchers unlock mystery of cartilage regeneration in lizards

Scientists from the Keck School of Medicine of USC identify key cells involved in the process of cartilage regeneration in lizards— a discovery which could offer insights into novel approaches to treating osteoarthritis.

Peer-Reviewed Publication

KECK SCHOOL OF MEDICINE OF USC

 

IMAGE: A GREEN ANOLE LIZARD REGENERATING ITS TAI. view more 

CREDIT: ARIEL VONK/LOZITO LAB

A team of researchers from the Keck School of Medicine of USC have published the first detailed description of the interplay between two cell types that allow lizards to regenerate their tails. This research, funded by the National Institutes of Health and published on August 10 in Nature Communications, focused on lizards’ unusual ability to rebuild cartilage, which replaces bone as the main structural tissue in regenerated tails after tail loss. 

The discovery could provide insight for researchers studying how to rebuild cartilage damaged by osteoarthritis in humans, a degenerative and debilitating disease that affects about 32.5 million adults in the United States, according to Centers for Disease Control and Prevention. There is currently no cure for osteoarthritis.

“Lizards are kind of magical in their ability to regenerate cartilage because they can regenerate large amounts of cartilage and it doesn’t transition to bone,” said the study’s corresponding author Thomas Lozito, assistant professor of orthopaedic surgery and stem cell biology and regenerative medicine at the Keck School of Medicine of USC. 

Lizards are among the only higher vertebrates capable of regenerating cartilage that does not ossify and are the closest relatives to mammals that can regenerate an appendage with multiple tissue types, including cartilage. Humans, by contrast, cannot repair cartilage that has been damaged once they reach adulthood. 

Lozito explained that understanding how organisms with super healing powers regenerate tissue could help researchers find ways to recreate those processes in mammals. 

“The dream is to find a way to translate that process in humans because they cannot repair cartilage,” said Lozito. “This represents an important step because we need to understand the process in great detail before we can try to recreate it in mammals.”

Key cells identified

First author Ariel Vonk, who is a PhD student in the Lozito Lab, and the research team determined that cells called fibroblasts, which help build tissue, are the critical cell type that builds cartilage in the lizard’s regenerated tail, the skeletons of which are almost entirely made of cartilage. The research described the changes in gene activity that took place among certain fibroblast cells that enabled cartilage building. 

They also discovered that a type of immune cell called a septoclast plays an important role in inhibiting fibrosis, or scarring, allowing the process of regeneration to take place. 

“Those two cell types working together laid the foundation for the beginning of the regenerative process,” said Lozito, who noted that a major difference between humans and lizards is that human tissue tends to scar and that scarring prevents tissue regeneration. 

One future avenue for research, said Lozito, is to use single-cell RNA sequencing to better describe the molecular mechanisms that halt scarring in lizards so that they can try to recreate the process in mammals. 

Cartilage regeneration induced in lizard limbs

Given what they learned about the cell types and molecular processes involved, the team ran tests to determine if they could recreate the process of rebuilding cartilage in lizard limbs which, unlike tails, do not regenerate after a loss. 

They extracted septoclasts from lizard tails and implanted them into limbs, which were deficient in pro-regenerative immune cells found to be responsible for inhibiting scarring. They were able to successfully induce cartilage building in a lizard limb by recreating a tail-like signaling environment.

Lozito added that they hope to test whether they can induce cartilage building in mammals, beginning with mice, using the techniques they employed in their experiments on lizard limbs. 

About the study

Additional authors of the study include Ariel Vonk, Xiaofan Zhao, Zheyu Pan, Megan Hudnall, Conrad Oakes, Gabriela Lopez, Sarah Hasel-Kolossa, Alexander Kuncz, Sasha Sengelmann, and Darian Gamble from the Keck School of Medicine of USC. 

The research was funded by the National Institutes of Health (R01GM115444), and support from the Molecular Genomics Core at the USC Norris Comprehensive Cancer Center. 

 

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-40206-z 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Single-cell analysis of lizard blastema fibroblasts reveals phagocyte-dependent activation of Hedgehog- responsive chondrogenesis

ARTICLE PUBLICATION DATE

10-Aug-2023