A new understanding of reptile coloration

A small sample of variations in coloring seen in captive-bred ball pythons (Python regius).
Image Credit: McGill University

Snakes and mice don’t look alike. But much of what we know about skin coloration and patterning in vertebrates generally, including in snakes, is based on lab mice. However, there are limits to what mice can tell us about other vertebrates because they don’t share all of the same types of color-producing cells, known as chromatophores. For example, snakes have a type of chromatophore called iridophores that can generate iridescent colors by reflecting light.

To gain a better understanding of the genetic basis of coloration in vertebrates, a McGill University-led research team combined a range of techniques (whole gene sequencing, gene-editing, and electron microscopy) to look more closely at color variations and patterning in the skin shed by ball pythons bred in captivity. They were able to identify a particular gene (tfec) that plays a crucial role in reptile pigmentation generally and more specifically in a classic color variant found across vertebrates and distinguished by blotches of white, the piebald.

Breakthrough laboratory confirmation of key theory behind the formation of planets, stars and supermassive black holes

Pillars of Creation: By combining images of the iconic Pillars of Creation from two cameras aboard NASA’s James Webb Space Telescope, the universe has been framed in its glory. The pillars are the vast clouds of dust and gas in the foreground that swirl around and form celestial bodies. 
Hi-Res Zoomable Image
Photo Credit: JWST/NASA

The first laboratory realization of the longstanding but never-before confirmed theory of the puzzling formation of planets, stars and supermassive black holes by swirling surrounding matter has been produced at the Princeton Plasma Physics Laboratory (PPPL). This breakthrough confirmation caps more than 20 years of experiments at PPPL, which is based at Princeton University.

The puzzle arises because matter orbiting around a central object does not simply fall into it, due to what is called the conservation of angular momentum that keeps planets and the rings of Saturn from tumbling from their orbits. That’s because the outward centrifugal force balances out the inward pull of gravity on the orbiting matter. However, the clouds of dust and plasma called accretion disks that swirl around and collapse into celestial bodies do so in defiance of the conservation of angular momentum.    

The solution to this puzzle, a theory known as the Standard Magnetorotational Instability (SMRI), was first proposed in 1991 by University of Virginia theorists Steven Balbus and John Hawley. They built on the fact that in a fluid that conducts electricity, whether the fluid be plasma or liquid metal, magnetic fields behave like springs connecting different sections of the fluid. This allows ubiquitous Alfvén waves, named after Nobel Prize winner Hannes Alfvén, to create a turbulent back-and-forth force between the inertia of the swirling fluid and the springiness of the magnetic field, causing angular momentum to be transferred between different sections of the disk.

Rates of hatching failure in birds almost twice as high as previously estimated

Hatching failure rates in birds are almost twice as high as experts previously estimated, according to the largest ever study of its kind.
Photo Credit: Michaela Wenzler

New study from the University of Sheffield, IoZ, and UCL found more than one in six bird eggs fail to hatch. Hatching failure increases as species decline, so the new research could be used to predict what species are most at risk of extinction.

The work provides evidence that conservation managers can use to support their decision making, creating the best possible outcomes for threatened bird species recovery.

The new report highlights how conservationists can best support the recovery of threatened bird species, as it outlines how different conservation practices may affect hatching rates.

Researchers from the University of Sheffield, Institute of Zoology, and University College London (UCL) looked at 241 bird species across 231 previous studies to examine hatching failure. They found that nearly 17 per cent of bird eggs fail to hatch - almost double the figure reported 40 years ago of just over nine per cent.

Researchers identify the neurons that synchronize female preferences with male courtship songs in fruit flies

Researchers discovered the strength of the response of a specific component of the auditory neuron circuit (shown in green) partly explain the fruit flies’ preferences for specific rhythms.
Image Credit: Takuro S. Ohashi 

When it comes to courtship, it is important to ensure that one is interacting with a member of the same species. Animals use multiple sensory systems to confirm that potential mates are indeed suitable, with acoustic communication playing an important role in their decision making.   

Although these differences have previously been reported at the behavioral level, it is not known how the neuronal circuitry underlying this decision-making has diverged between species. Now, in a new publication in Scientific Reports, a research group at Nagoya University in Japan has investigated how the auditory processing pathway has evolved and diverged between fruit fly species.  

Males of several species of Drosophila (fruit flies), which are regularly used in neuroscience research, vibrate their wings rhythmically during courtship, producing a courtship song. The temporal components of these songs differ between species, allowing female flies to distinguish between potential mates. 

Decades-old crustaceans coaxed from lake mud give up genetic secrets revealing evolution in action

 An ancient Daphnia pulicaria individual resurrected from South Center Lake (Minnesota, USA). This individual was hatched from an egg recovered from sediments that date back to circa 1418-1301 A. D. OU scientists have recently studied other members of this species to understand rapid evolution to human-caused pollution in lake ecosystems.
Image Credit: Dagmar Frisch

Human actions are changing the environment at an unprecedented rate. Plant and animal populations must try to keep up with these human-accelerated changes, often by trying to rapidly evolve tolerance to changing conditions.

University of Oklahoma researchers Lawrence Weider, professor of biology, and Matthew Wersebe, a biology doctoral candidate, demonstrated rapid evolution in action by sequencing the genomes of a population of Daphnia pulicaria, an aquatic crustacean, from a polluted lake.  

The research, which was conducted as part of Wersebe’s doctoral dissertation, was recently published in the Proceedings of the National Academy of Sciences.  Wersebe and Weider revived decades-old Daphnia resting eggs from lake sediments, a method known as resurrection ecology, which has been refined in Weider’s lab over the past several decades. They then sequenced the entire genomes of 54 different Daphnia individuals from different points-in-time, allowing them to study the genetics and evolution of the population.

Study reveals new clues about how 'Earth's thermostat' controls climate

The Amazon, Earth’s largest river, transporting weathering solutes from the Andes to the Atlantic Ocean in Brazil.
Photo Credit: Michael Vite

Rocks, rain and carbon dioxide help control Earth’s climate over thousands of years — like a thermostat — through a process called weathering. A new study led by Penn State scientists may improve our understanding of how this thermostat responds as temperatures change.

“Life has been on this planet for billions of years, so we know Earth’s temperature has remained consistent enough for there to be liquid water and to support life,” said Susan Brantley, Evan Pugh University Professor and Barnes Professor of Geosciences at Penn State. “The idea is that silicate rock weathering is this thermostat, but no one has ever really agreed on its temperature sensitivity.”

Because many factors go into weathering, it has been challenging to use results of laboratory experiments alone to create global estimates of how weathering responds to temperature changes, the scientists said.

The team combined laboratory measurements and soil analysis from 45 soil sites around the world and many watersheds to better understand weathering of the major rock types on Earth and used those findings to create a global estimate for how weathering responds to temperature.

Antibody possible treatment for severe fatty liver disease

Micrograph of non-alcoholic fatty liver disease (NAFLD). Masson's trichrome & Verhoeff stain. The liver has a prominent (centrilobular) macrovesicular steatosis (white/clear round/oval spaces) and mild fibrosis (green). The hepatocytes stain red.  Macrovesicular steatosis is lipid accumulation that is so large it distorts the cell's nucleus.
Image Credit: Nephron CC BY-SA 3.0

There is currently no drug for treating non-alcoholic fatty liver disease, which affects many people with type 2 diabetes and which can result in other serious liver diseases. A study led by researchers from Karolinska Institutet has now identified a drug candidate for the treatment of fatty liver. The preclinical study, published in the Journal of Hepatology, indicates that an antibody that blocks the protein VEGF-B presents a possible therapeutic option for fatty liver disease.

“Fatty liver is associated with several serious and sometimes fatal diseases,” says the study’s first author Annelie Falkevall, researcher at the Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Sweden. “With the therapeutic principle that we’ve developed, it might be possible to prevent fatty liver and hopefully lower the risk of liver failure and terminal liver cancer.”

For decades, obesity and overweight have been a common global disease that, amongst other problems, has caused a sharp rise in the incidence of type 2 diabetes. According to the Swedish Diabetes Association, there are 500,000 cases of diabetes in Sweden alone, of which 85 to 90 percent are type 2.

Harmful bacteria can elude predators when in mixed colonies

 Colonies of the bacterium V. cholerae (purple) insulate E. coli (yellow) from its natural predator
Image Credit: James Winans

Efforts to fight disease-causing bacteria by harnessing their natural predators could be undermined when multiple species occupy the same space, according to a study by Dartmouth College researchers.

When growing in mixed colonies, some harmful bacteria may be able to withstand attacks from the bacteria and viruses that target them by finding protection inside groups of rival species, according to a report published in the Proceedings of the National Academy of Sciences.

The researchers found that the intestinal bacterium Escherichia coli became surrounded by tightly packed colonies of Vibrio cholerae — which causes the deadly disease cholera — when the species were grown together. These clusters protected E. coli from the bacteria Bdellovibrio bacteriovorus that preys on both species individually, but in the study could only kill the outer layer of V. cholerae. This left the unscathed cells of E. coli and V. cholerae insulated within the colonies free to multiply.

Robots and A.I. team up to discover highly selective catalysts

Close up of the semi-automated synthesis robot used to generate training data
Photo Credit: ICReDD

Researchers used a chemical synthesis robot and computationally cost effective A.I. model to successfully predict and validate highly selective catalysts.

Artificial intelligence (A.I.) has made headlines recently with the advent of ChatGPT’s language processing capabilities. Creating a similarly powerful tool for chemical reaction design remains a significant challenge, especially for complex catalytic reactions. To help address this challenge, researchers at the Institute for Chemical Reaction Design and Discovery and the Max Planck Institut für Kohlenforschung have demonstrated a machine learning method that utilizes advanced yet efficient 2D chemical descriptors to accurately predict highly selective asymmetric catalysts—without the need for quantum chemical computations.  

“There have been several advanced technologies which can “predict” catalyst structures, but those methods often required large investments of calculation resources and time; yet their accuracy was still limited,” said joint first author Nobuya Tsuji. “In this project, we have developed a predictive model which you can run even with an everyday laptop PC.”

Signal transmission in the immune and nervous system using NEMO

Jörg Tatzelt, Konstanze Winklhofer and Simran Goel (from left) carried out the investigations together.
 Photo Credit: RUB, Marquard

Certain biomolecules in the form of active complexes temporarily accumulate in cells. This can be crucial for their functionality.

When transmitting signals within cells, many individual steps interlock. Among other things, proteins are provided with certain building blocks that switch their function on or off. In order to ensure fast signal transmission, these building blocks accumulate in the cell at certain locations for a limited time; Researchers speak of biomolecular condensates. A team around Prof. Dr. Konstanze Winklhofer, head of the Molecular Cell Biology Chair at the Ruhr University Bochum, has shown that the NEMO protein also forms condensates and which mechanism underlies NEMO condensate formation. The findings are important for understanding signal transmissions in the immune and nervous systems. The researchers report in the Life Science Alliance journal.