Female butterflies breed despite male shortage

Monarch Butterfly
Photo Credit: Erin Minuskin

Female monarch butterflies have no trouble finding a mate – even when a parasite kills most of the males, new research shows.

Some females carry a parasite called Spiroplasma that kills all their male offspring, meaning highly infected populations have very few males.

But the new study – by the universities of Exeter, Rwanda and Edinburgh, and the Dian Fossey Gorilla Fund – found females mated about 1.5 times on average, regardless of how many males were around.

The male proportion dropped below 10% in some cases, but it appears the remaining hard-working males managed to breed with most of the available females.

10-20% of females remained unmated, only slightly higher than the expected average in a population with plenty of males (5-10%).

Researchers invent novel ingestible capsule X-ray dosimeter for real-time radiotherapy monitoring

Prof Liu Xiaogang (left) and Dr Hou Bo from the NUS Department of Chemistry were key members of the team that developed the novel capsule dosimeter.
Photo Credit: National University of Singapore

Affordable and ingestible capsule monitors radiation dose, pH and temperature in the gastrointestinal tract in real time, and could benefit gastric cancer patients undergoing radiotherapy

Gastric cancer is one of the most common cancers worldwide. A new invention by researchers from the National University of Singapore (NUS) could help improve the treatment of this cancer by enhancing the precision of radiotherapy, which is commonly used in combination with treatment options such as surgery, chemotherapy or immunotherapy.

In the field of modern radiotherapy, precision in targeting tumor tissue while minimizing damage to healthy tissue is crucial. However, low efficacy and variable outcomes remain a challenge due to patient diversity, treatment uncertainty, and differences in delivery types. Monitoring the dose of radiation delivered and absorbed in real-time, particularly in the gastrointestinal tract, could enhance the precision of radiotherapy to improve its effectiveness, but it is difficult to achieve. Additionally, existing methods used for monitoring biochemical indicators such as pH and temperature are inadequate for comprehensive evaluation of radiotherapy.

Personalized Gut Microbiome Analysis for Colorectal Cancer Classification with Explainable AI

Explainable AI offers a promising solution for finding links between diseases and certain species of gut bacteria, finds a research team at Tokyo Tech. Using a concept borrowed from game theory, the researchers developed a framework that reveals which bacterial species are closely associated with colorectal cancer in individual subjects, providing a more reliable way to find and characterize disease subgroups and identify biomarkers in the gut microbiome.

The gut microbiome comprises a complex population of different bacterial species that are essential to human health. In recent years, scientists across several fields have found that changes in the gut microbiome can be linked to a wide variety of diseases, notably colorectal cancer (CRC). Multiple studies have revealed that a higher abundance of certain bacteria, such as Fusobacterium nucleatum and Parvimonas micra, is typically associated with CRC progression.

Ambrosia beetles can recognize their food fungi by their scents

Nest of a black stem borer (Xylosandrus germanus) in a hazelnut branch with adult females (large), a male (small) and individual larvae. The greyish fungal coating of the food fungus is visible on the walls of the tunnel system.
Photo Credit: Antonio Gugliuzzo

Experiments at the University of Freiburg provide evidence for the first time of the ability of ambrosia beetles to distinguish between food and harmful fungi

Certain ambrosia beetles species engage in active agriculture. As social communities, they breed and care for food fungi in the wood of trees and ensure that so-called weed fungi spread less. Researchers led by Prof. Dr. Peter Biedermann, professor of Forest Entomology and Forest Protection at the University of Freiburg, now demonstrates for the first time that ambrosia beetles can distinguish between different species of fungi by their scents. "The results can contribute to a better understanding of why beetles selectively colonize trees with conspecifics and how exactly their fungiculture works," says Biedermann. "In addition, the scents of the fungi could be used to develop attractants to control non-native ambrosia beetles."

Curtin researchers map genetic signature of precursor to liver cancer

Photo Credit: Julia Koblitz

Researchers at Curtin University have identified the genetic signature of pre-malignant liver cells, offering potentially significant implications for the almost 3,000 Australians diagnosed with the deadly cancer each year.

The study, published in the prestigious journal Cell Genomics, found that quantifying pre-malignant liver cells in patients with liver disease could help determine their future risk of developing liver cancer.

First author Dr Rodrigo Carlessi, from the Curtin Medical School and the Curtin Health Innovation Research Institute, said the discovery had the potential to save lives by changing how chronic liver disease patients are staged and monitored based on their cancer risk.

“The research used cutting-edge technology to identify the molecular fingerprint of thousands of genes, one cell at a time,” Dr Carlessi said.

“During this process, we discovered the genetic signature and its diagnostic value, which was subsequently confirmed in several hundred individual patient liver samples.

How rainforest fish adapt to habitat

Eastern rainbowfish from the Wet Tropics region of Australia.
Photo Credit: Keith Martin.

The future of freshwater fish species in Australia’s tropical rainforest areas, including the Daintree and Mosman Gorge, will increasingly be subject to the vagaries of climatic and other changes.

Flinders University molecular ecology researchers have led an in-depth study of the colorful eastern rainbowfish for clues about how their populations have adapted to local conditions in the creeks and rivers of the wet tropical areas of Far North Queensland.

Their study, published in the Nature journal Heredity, provides insights into what drives genetic diversity in Australian eastern rainbowfish (Melanotaenia splendida splendida) – highlighting the ways their biodiversity may be affected, and conserved, particularly with any increase in climate change rates.

“Tropical rainforests are home to a staggering variety of plants and animals, ranking them among Earth’s greatest biodiversity hotspots,” says postdoctoral research fellow Dr Katie Gates, first author on the new paper.

Benefits of “Zombie” Cells: Senescent Cells Aid Regeneration in Salamanders

The salamander species studied by the Yun group: a red spotted newt Notophthalmus viridescens.
Photo Credit: Dr. Maximina Yun

Scientists show that so-called senescent cells, i.e., cells that have permanently stopped dividing, boost production of new muscle cells to enhance regeneration of lost limbs in salamanders.

Senescent cells, often referred to as "zombie" cells, have long been associated with aging and disease. However, a new study from the Center for Regenerative Therapies Dresden (CRTD) at TU Dresden adds to a growing body of evidence that not all senescent cells are harmful. The study led by Dr. Maximina Yun shows that these cells can play a beneficial role in regeneration. Her team found that senescent cells boost muscle formation in regenerating salamander limbs. Their findings reveal a new role for senescent cells and expand the understanding of the early events in the regeneration process. The research was published in the journal Aging Cell.

Senescent cells are cells that have permanently stopped dividing in response to cellular stress but have not died. As organisms age, the number of senescent cells in the body increases. This accumulation is currently considered one of the hallmarks of aging and has been linked to a variety of diseases, including cancer. However, the true nature of these cells may be more complex and context-dependent.

Study reveals how pollinators cope with plant toxins

Photo Credit: Dustin Humes

Pollinators such as honeybees produce special enzymes that detoxify defense chemicals produced by plants, new research shows.

Many plants produce alkaloids as protection against herbivores, and these toxins are also found in their nectar and pollen.

The new study, by the University of Exeter and Bayer AG, examined the genes of several species in a group called Hymenoptera – insects including bees, wasps, ants and sawflies that share a common ancestor about 280 million years ago.

Remarkably, all the species tested produce the same group of enzymes (the CYP336 family of cytochrome P450 enzymes) to tackle alkaloid toxins.

“These species differ greatly, but one thing they share is this ability to detoxify alkaloids,” said Dr Angie Hayward, from Exeter’s Penryn Campus in Cornwall.

Scientists Trace Key Innovation in Our Camera-like Vision to Bacteria

Photo Credit: Colin Lloyd

Discovery comes to light with evidence that vertebrates acquired a special protein from bacteria more than 500 million years ago

Humans and other organisms with backbones come equipped with an evolutionary marvel: eyes that function like cameras to provide a finely tuned visual system. Due to its complexity, Charles Darwin described the eye as one of the greatest potential challenges to his theory of natural selection through incremental evolutionary steps.

A notable difference between vertebrate and invertebrate vision is rooted in a unique protein responsible for the specialization of cells that are critical for vision. Mutations in the protein have been known to cause a variety of diseases such as retinitis pigmentosa, but its evolutionary origin has remained elusive with no obvious genetic precursor.

Small and simple key to evolution success of mammals

Artistic reconstruction of early mammal ancestors (species: Hadrocodium wui) shown hunting insect prey, illustrating how the adoption of an insectivorous diet and miniaturization played an important role in mammal evolution.
Illustration Credit: Dr Stephan Lautenschlager, University of Birmingham

Ancestors of modern mammals evolved into one of the most successful animal lineages by starting out small and simple, researchers have found.

A new study, published today in Communications Biology, shows that skull bones were successively reduced in early mammals around 150 to 100 million years ago.  

The research further demonstrated that alongside the reduction of skull bones, early mammals also became a lot smaller, some of which had a skull length of only 10-12 mm. This miniaturization considerably restricted the available food sources and early mammals adapted to feeding mostly on insects, allowing them to thrive in the shadows of dinosaurs.

In many vertebrate groups (animals with a back bone), such as fishes and reptiles, the skull and lower jaw are composed of numerous bones. This was also the case in the earliest ancestors of modern mammals over 300 million years ago.

Nanotubes as an optical stopwatch for the detection of messenger substances

Bochum research team: Linda Sistemich and Sebastian Kruß
Photo Credit: © RUB, Kramer

Carbon nanotubes not only lighten in the presence of dopamine, but also longer. The lighting duration can serve as a new measurement for the detection of messenger substances.

An interdisciplinary research team from Bochum and Duisburg has found a new way to detect the important messenger substance dopamine in the brain. The researchers used carbon nanotubes for this. In previous studies, the team led by Prof. Dr. Sebastian Kruß has already shown that the tubes light up in the presence of dopamine. Now the interdisciplinary group showed that the duration of the lighting also changes. "It is the first time that an important messenger like dopamine has been detected in this way," says Sebastian Kruß. “We are convinced that this will open up a new platform that will also enable better detection of other human messenger substances such as serotonin. "The work was a cooperation between Kruß’ two working groups in physical chemistry at the Ruhr University Bochum and the Fraunhofer Institute for Microelectronic Circuits and Systems (IMS).

The results are described by a team led by Linda Sistemich and Sebastian Kruß from the Ruhr University Bochum together with colleagues from the IMS and the University of Duisburg-Essen in the journal Angewandte Chemie - International Edition, published online on 9. March 2023.

Sugar molecule in blood can predict Alzheimer’s

Photo Credit: Gerd Altmann

Early diagnosis and treatment of Alzheimer’s disease requires reliable and cost-effective screening methods. Researchers at Karolinska Institutet have now discovered that a type of sugar molecule in blood is associated with the level of tau, a protein that plays a critical role in the development of severe dementia. The study, which is published in Alzheimer's & Dementia, can pave the way for a simple screening procedure able to predict onset ten years in advance.

“The role of glycans, structures made up of sugar molecules, is a relatively unexplored field in dementia research,” says the study’s first author Robin Zhou, medical student and affiliated researcher at the Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet. “We demonstrate in our study that blood levels of glycans are altered early during the development of the disease. This could mean that we’ll be able to predict the risk of Alzheimer’s disease with only a blood test and a memory test.”

In Alzheimer’s disease, the neurons of the brain die, which is thought to be a result of the abnormal accumulation of the proteins amyloid beta and tau. Clinical trials for Alzheimer’s drugs show that treatment should commence early in the pathological process, before too many neurons have died, to reverse the process before it is too late.

Research reveals dual nature of beneficial bacteria UD1022

UD post-doctoral researcher Amanda Rosier is lead author on two papers reporting on the behavior of UD1022, a UD-patented beneficial bacteria that can help protect alfalfa from fungal pathogens.
Photo Credits: Evan Krape and courtesy of Amanda Rosie

Alfalfa, also known in Latin as Medicago sativa, is an agricultural crop that is part of the legume family. It is known as a protein-rich food source for dairy cattle that is easily digested and can lead to increased milk production. This is good news if you are a fan of ice cream or other dairy products. 

However, alfalfa can be susceptible to common fungal diseases, such as spring black stem or root rot, that can limit crop yields.

A recent paper published in Plants by University of Delaware plant biologist Harsh Bais and postdoctoral researcher Amanda Rosier has shown that UD1022, a UD-patented beneficial bacteria, can protect alfalfa plants from fungal pathogens that cause plant disease.

The UD-patented microbe UD1022 is a unique strain of Bacillus subtilis, a natural, beneficial bacterium that lives on the surface of roots and the surrounding soil, or rhizosphere. UD1022 is known as a growth promoter that can help plants flourish vigorously. It also is considered a plant protector for its ability to help plants wage a system-wide resistance when under attack by one of these microscopic disease agents.

Scientists uncover a key chemical structure in pigment molecule

Photo Credit: NCI

After nearly a century of scientific inquiry, scientists have at last been able to characterize a key component in the substance responsible for giving countless living organisms their color. 

In the study, published online today in the journal Nature Chemistry, an international team of researchers isolated a key molecule involved in the synthesis of melanin, a substance in the human body that produces pigmentation in the hair and skin and protects the cells from being damaged by ultraviolet radiation from the sun. The molecule they studied has many of the physical properties of eumelanin, a type of melanin that typically produces only black and brown pigments. 

Despite what researchers know about melanin, its chemical structure has remained elusive, said Bern Kohler, an Ohio Eminent Scholar and professor of chemistry and biochemistry at The Ohio State University, one of three senior authors on the study.  

“Melanin is literally as plain as the nose on our face and we still don't know exactly what it's made of and how it works,” said Kohler. “It's thought to be a material made of large numbers of interacting components, and so what my collaborators and I are trying to get at is, what are melanin’s underlying chemical units and what are the interactions that give rise to its properties?”

AI predicts enzyme function better than leading tools

An Illinois research team created an AI tool to predict an enzyme’s function from its sequence using the campus network and resource group servers. Pictured, from left: Tianhao You, Haiyang (Ocean) Cui, Huimin Zhao and Guangde Jiang.   
Photo Credit: Fred Zwicky

A new artificial intelligence tool can predict the functions of enzymes based on their amino acid sequences, even when the enzymes are unstudied or poorly understood. The researchers said the AI tool, dubbed CLEAN, outperforms the leading state-of-the-art tools in accuracy, reliability and sensitivity. Better understanding of enzymes and their functions would be a boon for research in genomics, chemistry, industrial materials, medicine, pharmaceuticals and more.

“Just like ChatGPT uses data from written language to create predictive text, we are leveraging the language of proteins to predict their activity,” said study leader Huimin Zhao, a University of Illinois Urbana-Champaign professor of chemical and biomolecular engineering. “Almost every researcher, when working with a new protein sequence, wants to know right away what the protein does. In addition, when making chemicals for any application – biology, medicine, industry – this tool will help researchers quickly identify the proper enzymes needed for the synthesis of chemicals and materials.”

The researchers will publish their findings in the journal Science and make CLEAN accessible online March 31.

Allies or enemies of cancer: the dual fate of neutrophils

Neutrophils infiltrating tumors are heterogeneous and different neutrophil types can have opposing effects on cancer progression. The image shows artistic rendering of a lung tumor nodule (in blue) infiltrated by various neutrophil types (shown in green, orange and red) including some (in red) that are expanded by immunotherapy and are required for tumor elimination.
Illustration Credit: © Mate Kiss, Evangelia Bolli and Mikael Pittet

An international team including scientists from the UNIGE and Harvard has discovered a new type of immune cell whose action is essential for the success of immunotherapies.

Why do cancer immunotherapies work so extraordinarily well in a minority of patients, but fail in so many others? By analyzing the role of neutrophils, immune cells whose presence usually signals treatment failure, scientists from the University of Geneva (UNIGE), from Harvard Medical School, and from Ludwig Cancer Center have discovered that there is not just one type of neutrophils, but several. Depending on certain markers on their surface, these cells can either promote the growth of tumors, or fight them and ensure the success of a treatment. By boosting the appropriate factors, neutrophils could become great agents of anti-tumor immunity and reinforce the effects of current immunotherapies. These results can be read in Cell.

A key mechanism that controls human heart development discovered

A human cardiac organoid (Cardioid), one of the models the researchers used to reconstruct human cardiac development in 3D. Cardiac mesoderm stage human Cardioid visualizing Phalloidin (grey) and β-catenin (Magenta).
Image Credit: Deniz Bartsch

Writing in ‘Science Advances’ researchers of the University of Cologne describe a key mechanism that controls the decision-making process that allows human embryonic stem cells to make the heart. These discoveries enable better insights into how the human heart forms in an embryo and what can go wrong during heart formation, causing cardiac disease or, in the worst case, embryo termination.

In humans, a specialized mRNA translation circuit predetermines the competence for heart formation at an early stage of embryonic development, a research team at the Center for Molecular Medicine Cologne (CMMC) and the University of Cologne’s Cluster of Excellence in Aging Research CECAD led by Junior Professor Dr Leo Kurian has discovered. While it is well known that cardiac development is prioritized at the early stages of embryogenesis, the regulatory program that controls the prioritization of the development of the heart remained unclear until now. Kurian and his team investigated how the prioritization of heart development is regulated at the molecular level. They found that the protein RBPMS (RNA-binding protein with multiple splicing) is responsible for the decision to make the heart by programming mRNA translation to approve future cardiac fate choice. The study is published under the title ‘mRNA translational specialization by RBPMS presets the competence for cardiac commitment’ in Science Advances.

Rainbow Trout Subspecies Newly Named

The McCloud River Redband Trout is known as “cali sulat” in the Winnemem Wintu language, with “cali” meaning good or beautiful and “sulat” the term for trout.
Photo Credit: Steve MacMillan

The McCloud River redband trout, or O. mykiss calisulat, is newly identified as its own distinct subspecies of rainbow trout in a study from the University of California, Davis. It is the first newly identified subspecies of Pacific trout since 2008 and the youngest rainbow trout subspecies by more than 100 years.

The study, published in the journal Zootaxa, notes that fish biologists have suspected the McCloud River redband trout was its own subspecies since at least the 1970s, but only newer genetics techniques — including genomewide DNA sequencing — allowed the UC Davis-led team to tease the puzzle apart and confirm it as a subspecies.

Northern California’s McCloud River originates from spring-fed streams near Mount Shasta before passing over a series of waterfalls, the McCloud Falls. The waterfalls are impassable to upstream movement of fishes and divide the Upper McCloud River from the Lower McCloud River.

The McCloud River redband trout is the only known native fish found in the Upper McCloud Basin.

“It’s persisted so long in isolation,” said lead author Matthew “Mac” Campbell, a research affiliate with the Department of Animal Science’s Genomic Variation Laboratory. “They’ve survived in glacial refugia during the Pleistocene era and have been above those waterfalls for at least 10,000 years.”

Cell mapping and ‘mini placentas’ give new insights into human pregnancy

Cells of the placenta 
Image Credit: Kenny Roberts, Wellcome Sanger Institute

Researchers from the University of Cambridge, the Wellcome Sanger Institute, the Friedrich Miescher Institute for Biomedical Research (FMI), Switzerland, EMBL’s European Bioinformatics Institute (EMBL-EBI), and collaborators, have created an in-depth picture of how the placenta develops and communicates with the uterus.

The study, published today in the journal Nature, is part of the Human Cell Atlas initiative to map every cell type in the human body. It informs and enables the development of experimental models of the human placenta.

"For the first time, we have been able to draw the full picture of how the placenta develops and describe in detail the cells involved in each of the crucial steps. This new level of insight can help us improve laboratory models to continue investigating pregnancy disorders, which cause illness and death worldwide,” said Anna Arutyunyan, co-first author at the University of Cambridge and Wellcome Sanger Institute.

The placenta is a temporary organ built by the fetus that facilitates vital functions such as fetal nutrition, oxygen and gas exchange, and protects against infections. The formation and embedding of the placenta into the uterus, known as placentation, is crucial for a successful pregnancy.

Smells influence metabolism and ageing in mice

Photo Credit: Nick Fewings

Exposure to female odors and pheromones causes weight loss and extend the life spans of mice, which may have implications for humans, University of Otago researchers have found.

Lead researcher Dr Michael Garratt, of the Department of Anatomy, says while it was already known that sensory cues in humans and animals influence the release of sex hormones, this study shows that these cues could have more wide-spread physiological effects on metabolism and ageing.

“Our studies show that female odors slow the sexual development of female mice, but consequently extends their lifespan. And we also show that the smell of females can increase male mouse energy expenditure, which subsequently influences their body weight and body fat levels,” he says.

Newborn mice were exposed to odors from adult females until they were 60 days old. Those females exposed to the odors reached sexual maturity later and lived an average 8 per cent longer than those not exposed.

There was no effect of male odors on female mouse lifespan, or changes in lifespan in males in response to odors from either sex.