New lab-grown human embryo model produces blood cells

Video Credit: University of Cambridge

Researchers have found a new way to produce human blood cells in the lab that mimics the process in natural embryos. Their discovery holds potential to simulate blood disorders like leukemia, and to produce long-lasting blood stem cells for transplants.

University of Cambridge scientists have used human stem cells to create three-dimensional embryo-like structures that replicate certain aspects of very early human development - including the production of blood stem cells.

Human blood stem cells, also known as hematopoietic stem cells, are immature cells that can develop into any type of blood cell, including red blood cells that carry oxygen and various types of white blood cells crucial to the immune system.

The embryo-like structures, which the scientists have named ‘hematoids’, are self-organizing and start producing blood after around two weeks of development in the lab - mimicking the development process in human embryos.

Ural Scientists Have Discovered Unknown Lichen Species in China

The discoveries were made during a large-scale expedition to the provinces of Gansu and Yunnan
Photo Credit: Courtesy of Ural Federal University

Scientists from UrFU Department of Biodiversity and Bioecology with their colleagues from Taizhou University (China) have discovered unknown lichen species in China. The samples were collected during a large-scale expedition in the provinces of Gansu and Yunnan. Scientists plan to publish a description of the new species in a scientific journal.

“We repeated two expeditions that took place 100 years ago. In the province of Yunnan, we explored the areas where an expedition led by the Austrian botanist, Heinrich von Handel-Mazzetti, was conducted in 1914-1916. In Gansu province, we collected material on the route of the Sino-Swedish expedition led by Sven Hedin in 1927-1935,” said Alexander Paukov, a member of the expedition and professor at UrFU Department of Biodiversity and Bioecology.

Deciphering the mechanisms of genome size evolution

The sequencing of the genomes of a spider from the mainland (Dysdera catalonica, left) and one from the Canary Islands (Dysdera tilosensis, left) opens a new perspective for understanding how genome size evolves in similar species, an enigma that has baffled the scientific community for years.
Photo Credit: Courtesy of University of Barcelona

This study contradicts the more traditional evolutionary view — on island-colonizing species, whose genomes are larger and often have more repetitive elements — and expands the scientific debate on a major puzzle in evolutionary biology: how and why does genome size change during the evolution of living beings?

The study is led by Julio Rozas and Sara Guirao, experts from the Faculty of Biology and the Biodiversity Research Institute (IRBio) of the University of Barcelona. The paper, whose first author is Vadim Pisarenco (UB-IRBio), also involves teams from the University of La Laguna, the Spanish National Research Council (CSIC) and the University of Neuchâtel (Switzerland).

This research offers a surprising perspective to explain a phenomenon that has puzzled scientists for decades: the size of the genome — the total number of DNA base pairs encoding an organism’s genetic information — varies enormously between species, even those with similar biological complexity.

Burning issue: study finds fire a friend to some bees, a foe to others

Native bee species the megachile aufrions.
Photo Credit: Kit Prendergast

New Curtin University research has found the impact of bushfires and prescribed burns on global bee populations is highly varied, with some species benefiting from fire while others face severe risks.

The study, led by Adjunct Research Fellow Dr Kit Prendergast from Curtin’s School of Molecular and Life Sciences, examined 148 studies from around the world to understand how fire impacts bees.

The review considered the severity, frequency and duration of fires, along with the different characteristics of bees, such as where they nest, their body size, how specialized their diet is and whether they live alone or in groups.

Dr Prendergast said while declining pollinator numbers are being increasingly recognized as a major threat to biodiversity and sustainability, little was known until now about how they respond to fires that are becoming more frequent and severe due to climate change and land management practices.

Old Puzzle around Protein Distribution in Plant Cells Solved

Lei Zhang works with the plant Arabidopsis.
Photo Credit: © RUB, Marquard

How lipids in the membrane of the endoplasmic reticulum of plant cells interact with proteins to organize the first step of protein transport has long been an unsolved mystery. A research team at Ruhr University Bochum, Germany, led by Professor Christopher Grefen, has uncovered how a lipid switch in plant cells directs proteins to the endoplasmic reticulum (ER) – the gateway to the cell’s secretory pathway. The study was published in the journal Proceedings of the National Academy of Sciences. 

Researchers develop functional eggs from human skin cells

Researchers at OHSU have demonstrated a new technique to treat infertility by turning skin cells into oocytes, or eggs. Shown here, an image of an oocyte with a bright image of a skin cell nucleus before fertilization.
Image Credit: Oregon Health & Science University

Researchers at Oregon Health & Science University have accomplished a unique proof of concept to treat infertility by turning skin cells into eggs capable of producing early human embryos.

The research published today in the journal Nature Communications.

The development offers a potential avenue for in vitro gametogenesis — the process of creating gametes — to treat infertility for women of advanced maternal age or those who are unable to produce viable eggs due to previous treatment of cancer or other causes.

Why mamba snake bites worsen after antivenom

Photo Credit: Johan Marais

A breakthrough study at The University of Queensland has discovered a hidden dangerous feature in the Black Mamba, one of the most venomous snakes in the world.

Professor Bryan Fry from UQ’s School of the Environment said the study revealed  the venoms of 3 species of mamba were far more neurologically complex than previously thought, explaining why antivenoms were sometimes ineffective.

“The Black Mamba, Western Green Mamba and Jamesons Mamba snakes aren’t just using one form of chemical weapon, they’re launching a coordinated attack at 2 different points in the nervous system,” Professor Fry said.

“If you’re bitten by 3 out of 4 mamba species, you will experience flaccid or limp paralysis caused by postsynaptic neurotoxicity.

“Current antivenoms can treat the flaccid paralysis but this study found the venoms of these 3 species are then able to attack another part of the nervous system causing spastic paralysis by presynaptic toxicity.

Cell death in microalgae resembles that in humans

Under the microscope, it is possible to see for the first time how microalgae undergo the same type of programmed cell death as animal cells. (Microalgae in purple and apoptotic bodies as small dots.)
 Image Credit: Luisa Fernanda Corredor Arias

For the first time, researchers at Umeå University have observed the same type of programmed cell death in microalgae as in humans. The discovery, published in Nature Communications, shows that this central biological process is older than previously thought.

“This is the first photosynthetic organism, and the first single-cell organism, shown to produce so called apoptotic bodies during cell death. This proves that apoptosis, a pathway of programmed cell death which was thought to be unique to animals, is more ancient and widespread than previously believed,” says Christiane Funk, Professor at the Department of Chemistry, Umeå University.

Cells can die naturally from age or disease, but organisms can also actively trigger the death of certain cells when needed. This is known as programmed cell death (PCD), a central biological system that allows the development of organs in our bodies and provides advantage during an organism’s life cycle. One example is the differentiation of fingers in a developing human embryo; others are the control of cell numbers or the elimination of non-functional cells.

How Botox enters our cells

Volodymyr M. Korkhov (left) and Richard Kammerer of the Center for Life Sciences at PSI have made important advances towards understanding how botulinum neurotoxin, botox for short, enters our nerve cells.
Photo Credit: © Paul Scherrer Institute PSI/Mahir Dzambegovic

Botulinum toxin A1, better known under the brand name Botox, is not only a popular cosmetic agent, but also a highly effective bacterial neurotoxin that – when carefully dosed – can be used as a drug. It blocks the transmission of signals from nerves to muscles: This can relax muscles under the skin, which in cosmetics is used to smooth facial features. It can also alleviate conditions that are caused by cramping muscles or faulty signals from nerves, such as spasticity, bladder weakness, or misalignment of the eyes. However, if the dose is too high, the use of Botox can be fatal due to paralysis of the respiratory muscles. This can happen as a result of bacterial meat poisoning and is called botulism.

To make the most effective use of botulinum toxin as a drug, to precisely control its action, and to expand the range of possible applications of the toxin, researchers want to better understand how the toxin enters nerve cells to exert its effect. Until now, little was known about this.  “This is mainly because we had no structural data on what the toxin looks like in its full-length form when binding to its nerve cell's receptor,” says Richard A. Kammerer of the PSI Center for Life Sciences. So far there had only been studies on the structure of individual domains of the toxin – that is, specific parts of its complex molecular structure – and on the structure of such domains in complex with the receptor or one of its domains. 

Purdue biochemists discover self-repair function in key photosynthetic protein complex

Sujith Puthiyaveetil and Steve McKenzie look at a plant thylakoid in a lab at the biochemistry building at Purdue University.
Photo Credit: Purdue Agricultural Communications/Joshua Clark

Cyanobacteria began contributing oxygen to Earth’s mostly noxious atmosphere more than 2 billion years ago. The photosystem II protein complex now shared by various lineages of cyanobacteria, algae and land plants has served as a major site of oxygen production throughout the history of life on Earth ever since.

Ironically, receiving too much light can damage photosystem II and erode the photosynthetic efficiency of plants. Purdue University biochemists Steven McKenzie and Sujith Puthiyaveetil have gleaned new, long-hidden details about how photosystem II repairs itself. McKenzie and Puthiyaveetil’s findings have been published in the journal Plant Communications.

“The photosystem II splits water and extracts electrons and protons, leaving oxygen as a by-product. Photosystem II thereby powers life on Earth,” said Puthiyaveetil, associate professor of biochemistry. Even so, “it’s still fairly poorly understood how these huge protein complexes that use light energy to produce oxygen are able to be repaired and maintained so efficiently across different lineages of plants, algae and cyanobacteria.”

Research in Fruit Flies Pinpoints Brain Pathways Involved in Alcohol-Induced Insomnia

Adrian Rothenfluh, PhD (left), and Maggie Chvilicek (right), authors on the recent study.
Photo Credit: Courtesy of University of Utah Health

Alcohol use disorder, which affects over 10% of Americans, can lead to persistent and serious insomnia. Difficulties falling asleep and staying asleep can last even after months of sobriety, increasing the risk of relapse. But treating withdrawal-related insomnia is difficult, partly because what’s going on in the brain in this condition remains largely mysterious.

 Now, research in fruit flies has identified specific brain signals and groups of brain cells that are involved in alcohol-induced insomnia. This work could ultimately lead to targeted treatments for alcohol-related sleep loss, helping people recover from alcohol use disorder.

  “The effects of alcohol on sleep seem to be localized to a particular cell type in the brain, which is not something that’s ever been shown before,” says Maggie Chvilicek, graduate researcher in neuroscience at the University of Utah and lead author on the study. She adds that these cells often do similar things in flies and humans. “The mechanism that we identified is something that very likely could also exist in a mammalian brain.”

Native bee populations can bounce back after honey bees move out

A native bee sits on a purple flower on the left, while a honey bee sits on a yellow flower on the right.  Photo Credit: © Margarita López-Uribe

Managed honey bees have the potential to affect native bee populations when they are introduced to a new area, but a study led by researchers at Penn State suggests that, under certain conditions, the native bees can bounce back if the apiaries are moved away.

The research, published in the Journal of Insect Science, examined the effects of migratory beekeeping — the practice of moving honey bee colonies to a different location for part of the year — on native bee populations. 

The researchers found that when managed honey bees were moved into an area, the population of native bees decreased in abundance and diversity. However, in places where apiaries were kept for years and then removed, the native bee populations once again increased in both total numbers and species diversity.

Margarita López-Uribe, the Lorenzo L. Langstroth Early Career Professor of Entomology in the College of Agricultural Sciences and co-author of the paper, said the findings suggest that while migratory beekeeping can be a disturbance to native bees, it may also be possible for those populations to recover.

Quantum mechanics helps with photosynthesis

First author Erika Keil and Prof. Jürgen Hauer in the lab.
Photo Credit: Andreas Heddergott / TUM

Photosynthesis - mainly carried out by plants - is based on a remarkably efficient energy conversion process. To generate chemical energy, sunlight must first be captured and transported further. This happens practically loss-free and extremely quickly. A new study by the Chair of Dynamic Spectroscopy at the Technical University of Munich (TUM) shows that quantum mechanical effects play a key role in this process. A team led by Erika Keil and Prof. Jürgen Hauer discovered this through measurements and simulations.

The efficient conversion of solar energy into storable forms of chemical energy is the dream of many engineers. Nature found a perfect solution to this problem billions of years ago. The new study shows that quantum mechanics is not just for physicists but also plays a key role in biology.

Photosynthetic organisms such as green plants use quantum mechanical processes to harness the energy of the sun, as Prof. Jürgen Hauer explains: “When light is absorbed in a leaf, for example, the electronic excitation energy is distributed over several states of each excited chlorophyll molecule; this is called a superposition of excited states. It is the first stage of an almost loss-free energy transfer within and between the molecules and makes the efficient onward transport of solar energy possible. Quantum mechanics is therefore central to understanding the first steps of energy transfer and charge separation.”

Videos with Cold Symptoms Activate Brain Regions and Trigger Immune Response

 Study on Brain Activity and Antibody Concentration
Photo Credit: Andrea Piacquadio

People who watch videos of sneezing or sick people show increased activity in brain regions that represent an interface between the brain and the immune system and react to potential dangers. At the same time, the concentration of antibodies in their saliva increases. The findings of a study by researchers from the Department of Biology at the University of Hamburg indicate that an important part of the immune system responds even before a pathogen enters the body. The results were published in the journal Brain Behavior and Immunity.

Throughout human history, communicable diseases, especially viral respiratory infections such as SARS-CoV-2 or influenza, have been among the main factors that significantly influence human mortality. The constant threat of pathogen transmission has led to the development of various physiological mechanisms of the immune system - for example, the body releases proteins to fight pathogens in the body.

Regulatory T Cells Found to Safeguard Brain Health, Memory Formation

Differences in neuronal activation in mice with intact Tregs (left) and depleted Tregs (right). The finding demonstrates that Tregs play a role in ensuring healthy neuronal activity under normal conditions.
Image Credit: Mathis/Benoist Lab

Immune cells called regulatory T cells have long been known for their role in countering inflammation. In the setting of infection, these so-called Tregs restrain the immune system to ensure it doesn’t go into overdrive and mistakenly attack the body’s own organs.

Now scientists at Harvard Medical School have discovered a distinct population of Tregs dwelling in the protective layers of the brains of healthy mice with a repertoire much broader than inflammation control.

The research, published Jan. 28 in Science Immunology, shows that these specialized Tregs not only control access to the inner regions of the brain but also ensure the proper renewal of nerve cells in an area of the brain where short-term memories are formed and stored.

The research, funded in part by the National Institutes of Health, represents an important step toward untangling the complex interplay of immune cells in the brain. If replicated in further animal studies and confirmed in humans, the research could open up new avenues for averting or mitigating disease-fueling inflammation in the brain.

A genome-wide atlas of cell morphology reveals gene functions

Human cells imaged using Cell Painting. Cell nuclei are shown in blue, actin filaments in yellow, the endoplasmic reticulum in magenta, golgi bodies in cyan, and mitochondria in green.
Image Credit: Maria Lozada, Neal Lab

Visualizing cells after editing specific genes can help scientists learn new details about the function of those genes. But using microscopy to do this at scale can be challenging, particularly when studying thousands of genes at a time.

Now, researchers at the Broad Institute of MIT and Harvard, along with collaborators at Calico Life Sciences, have developed an approach that brings the power of microscopy imaging to genome-scale CRISPR screens in a scalable way. 

PERISCOPE — which stands for perturbation effect readout in situ via single-cell optical phenotyping — combines two technologies developed by Broad scientists: Cell Painting, which can capture images and key measures of subcellular compartments at scale, and Optical Pooled Screening, which “barcodes” cells and uses CRISPR to systematically turn off individual genes to study their function in those cells. 

The new technique lets scientists study the effects of perturbing over 20,000 genes on hundreds of image-based cellular features. Generating data with this method is more than 10 times less expensive than comparable high-dimensional approaches such as high-throughput single-cell RNA sequencing and can be adapted to study a wide variety of cell types. In Nature Methods, the researchers applied PERISCOPE to execute three whole-genome CRISPR screens to create an open-source atlas of cell morphology.

OHSU researchers use AI machine learning to map hidden molecular interactions in bacteria

Andrew Emili, Ph.D., professor of systems biology and oncological sciences, works in his lab at OHSU. Emili is part of a multi-disciplinary research team that uncovered how small molecules within bacteria interact with proteins, revealing a network of molecular connections that could improve drug discovery and cancer research.
Photo Credit: OHSU/Christine Torres Hicks

A new study from Oregon Health & Science University has uncovered how small molecules within bacteria interact with proteins, revealing a network of molecular connections that could improve drug discovery and cancer research.

The work also highlights how methods and principles learned from bacterial model systems can be applied to human cells, providing insights into how diseases like cancer emerge and how they might be treated. The results are published today in the journal Cell.

The multi-disciplinary research team, led by Andrew Emili, Ph.D., professor of systems biology and oncological sciences in the OHSU School of Medicine and OHSU Knight Cancer Institute, alongside Dima Kozakov, Ph.D., professor at Stony Brook University, studied Escherichia coli, or E. coli, a simple model organism, to map how metabolites — small molecules essential for life — interact with key proteins such as enzymes and transcription factors. These interactions control important processes such as cell growth, division and gene expression, but how exactly they influence protein function is not always clear.

T cells rise up to fight infections in the gut

An image produced through Xenium analysis of mouse small intestines. Protruding “villi” stick up from the lining of the small intestine. Valley-like “crypts” fill in the gaps.
Image Credit: Reina Lab, La Jolla Institute for Immunology

Your gut is a battleground. The cells that line your small intestine have to balance two seemingly contradictory jobs: absorbing nutrients from food, while keeping a wary eye out for pathogens trying to invade your body.

“This is a surface where pathogens can sneak in,” says La Jolla Institute for Immunology (LJI) Assistant Professor Miguel Reina-Campos, Ph.D. “That’s a massive challenge for the immune system.”

So how do immune cells keep the gut safe? New research led by scientists at LJI, UC San Diego, and the Allen Institute for Immunology shows that pathogen-fighting immune cells called tissue-resident memory CD8 T cells (TRM cells) go through a surprising transformation—and relocation—as they fight infections in the small intestine.

In fact, these cells literally rise up higher in the tissue to fight infections before pathogens can spread to deeper, more vulnerable areas.

Researchers create lab model that could lead to new, non-hormonal birth control methods

Oregon Health & Science University researchers have developed a new lab model to study how changes in cervical mucus during the menstrual cycle help regulate fertility. This model could help develop new, non-hormonal birth control methods for women.
Photo Credit: OHSU/Christine Torres Hicks

Oregon Health & Science University researchers have developed a new lab model to study how changes in cervical mucus during the menstrual cycle help regulate fertility. This model could help develop new, non-hormonal birth control methods for women.

The study, published in the journal Biology of Reproduction, is part of ongoing work by senior author Leo Han, M.D., M.P.H., associate professor of obstetrics and gynecology in the OHSU School of Medicine and the OHSU Oregon National Primate Research Center. Han is a complex family planning specialist whose research focuses on developing new, non-hormonal contraceptives. 

In this study, his research team analyzed the genetic activity in lab-cultured cervical cells, identifying hundreds of different genes that could be drug targets for birth control that uses innovative new methods to block sperm. 

Polygamy is (not) for the birds

Rafael S. Marcondes, a faculty fellow in ecology and evolutionary biology at Rice
Photo Credit: Alex Becker/Rice University

Researchers at Rice University have uncovered new insights into the evolution of bird behavior, revealing why certain mating systems persist while others disappear over time. In a recent paper published in the journal Evolution, Rafael S. Marcondes and Nicolette Douvas reveal that lekking — a mating system where males display for females without forming lasting bonds — is an evolutionarily stable strategy. In contrast, resource-defense polygamy, where one sex — usually but not always the male — guards territories to attract mates, is highly unstable and often reverts to monogamy.

“This research not only examines how mating behaviors influence species survival but also sheds light on larger evolutionary questions,” said Marcondes, the corresponding author and a faculty fellow in ecology and evolutionary biology at Rice. “By studying birds, we’re uncovering principles that may resonate across other species too.”

The study analyzed data from more than 60% of the world’s bird species — approximately 6,620 species — making it one of the most comprehensive analyses of its kind.