Alternative pathways in proteasome biogenesis deciphered

 A new study conducted by researchers from the University of Potsdam and the University of Cologne has deciphered the step-by-step assembly of the eukaryotic proteasome. Eukaryotes are organisms whose cells have a clearly defined nucleus and different compartments within the cell. The proteasome is one of the key molecular machines responsible for the degradation of proteins that are defective or no longer needed within cells.

The central protease chamber of the proteasome consists of two identical halves, each composed of two rings comprising seven alpha or seven beta subunits. The two inner beta rings form a chamber in which defective proteins are broken down.

The study results, published in Nature Communications, titled "Structural transitions in the stepwise assembly of proteasome core particles," show that the assembly of this vital complex does not follow a rigid, linear pattern, but rather utilizes several alternative pathways—a discovery that challenges established views in research. The findings have far-reaching implications for understanding cellular protein quality control, aging and diseases such as cancer or neurodegenerative disorders, in which proteasome dysfunction plays a role. They also open up new avenues for the development of targeted drugs that influence proteasome biogenesis. Imaging early assembly intermediates Using high-resolution cryo-electron microscopy (cryo-EM),

a team led by Professor Dr. Petra Wendler of the University of Potsdam and Professor Dr. Jürgen Dohmen of the University of Cologne has characterized the structures of six early proteasome precursor complexes (13S-PC to 15S-PC) in yeast—including previously unknown intermediate stages. The data show that the proteasome can be assembled via two different pathways, which differ in the order in which the beta subunits are incorporated into the rings of the proteasome: one pathway in which the Beta1 subunit is incorporated first, followed by Beta5 and Beta6, and another in which Beta5 and Beta6 are incorporated first.

"That was a surprise," says Petra Wendler. "Beta1 can enter the complex independently of Beta5 and Beta6—an indication of a flexibility in proteasome biogenesis that we hadn't expected."

Chaperones guide and time activation The study also reveals how the assembly helper proteins Ump1 and Pba1-Pba2—so-called chaperons—control the assembly process. A previously unknown region of the Pba1 protein inserts between two alpha subunits and acts like a molecular wedge, keeping the central pore of the maturing proteasome open.

It is only released after the final stage of maturation, ensuring that the complex is only activated once it is fully assembled. Pba1-Pba2 is then recycled, while Ump1 is degraded by the mature proteasome. The results also show that the catalytic centers of the proteasome, where proteins are broken down after assembly, are only correctly structured—and thus activated—once the two halves (15S-PC) have joined together.


 This is mediated by the entry of the last of the seven beta subunits (Beta7). This mechanism prevents premature activation of the proteasome before the chamber is closed. "The assembly of the proteasome is a precisely choreographed process," says Jürgen Dohmen. "Our work demonstrates how structural changes in chaperons and proteasome subunits are precisely coordinated to ensure correct assembly of the proteasome and activation only once all components have taken up their correct positions."

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How Light Detects Disease in 29s #biophotonics #researchawards#lighting

Biophotonic probes for bio-detection and imaging are advanced optical tools designed to detect, monitor, and visualize biological processes with high sensitivity and precision. These probes interact with light to identify biomolecules, pathogens, and cellular structures in real time, enabling early disease diagnosis, targeted therapy monitoring, and improved biomedical research. #Biophotonics #BiophotonicProbes #BioDetection #BiomedicalImaging #OpticalBiosensors #FluorescenceImaging #Nanobiotechnology #MedicalDiagnostics #CancerDetection #OpticalImaging #LifeSciences #PhotonicsResearch #BiosensingTechnology #AdvancedDiagnostics #Spectroscopy #BiomedicalInnovation #HealthcareTechnology #SmartDiagnostics #OpticalProbes #BiotechResearch More Info: Visit: biophotonicsresearch.com Nominate Link: https://biophotonicsresearch.com/award-nomination/?ecategory=Awards&rcategory=Awardee Registration Link: https://biophotonicsresearch.com/award-registration/

Whaling’s Shadow: Bowheads in 30s #researchawards #biophotonics #biotechnology #biology

 Past intensive whaling pushed bowhead whales to the brink of extinction, drastically reducing their population over centuries. Known for their incredible lifespan and resilience in the Arctic, these whales are still recovering today. However, slow reproduction rates, climate change, increased shipping, and human activities continue to threaten their future.

#BowheadWhales #SaveTheWhales #MarineConservation #OceanLife #ArcticWildlife #ClimateChangeImpact #ProtectMarineLife #WildlifeConservation #EndWhaling #OceanEcosystem #SustainableFuture #NatureProtection #Biodiversity #EnvironmentalAwareness

Dinos hatched eggs less efficiently than modern birds, researchers show

 What do we really know about how oviraptors—bird-like but flightless dinosaurs—hatched their eggs? Did they use environmental heat, like crocodiles, or body heat from an adult, like birds? In a new Frontiers in Ecology and Evolution study, researchers in Taiwan examined the brooding behavior and hatching patterns of oviraptors. They also modeled heat transfer simulations of oviraptor clutches and compared hatching efficiency to modern birds. To do so, they experimented with a life-sized oviraptor incubator and eggs.

"We show the difference in oviraptor hatching patterns was induced by the relative position of the incubating adult to the eggs," said senior author Dr. Tzu-Ruei Yang, an associate curator of vertebrate paleontology at Taiwan's National Museum of Natural Science.

"Moreover, we obtained an estimate of the incubation efficiency of oviraptors, which is much lower than that of modern birds," added first author Chun-Yu Su, who attended Washington High School in Taichung when the research was conducted.

Building a dinosaur

The reconstructed oviraptor, Heyuannia huangi, lived between 70 and 66 million years ago in what today is China. Estimated to be around 1.5 meters long and weighing around 20 kg, it built semi-open nests made up of several rings of eggs.

The incubating oviraptor's trunk was made from polystyrene foam and wood for the skeletal frame and cotton, bubble paper, and cloth for the soft tissue. Eggs were molded from casting resin. In the two clutches used in the experiments, eggs were arranged in double-rings based on real oviraptor clutches.

"Part of the difficulty lies in reconstructing oviraptor incubation realistically," said Su. "For example, their eggs are unlike those of any living species, so we invented the resin eggs to approximate real oviraptor eggs as best as we could."

When the team ran experiments to find out if clutch attendance of a brooding adult or different environmental circumstances may have impacted hatching patterns, they found that in colder temperatures, where a brooding adult attended the clutch, the eggs' temperatures in the outer ring differed by up to 6°C, which could have resulted in asynchronous hatching, a pattern where eggs in the same nest hatch at different times.

In warmer conditions, the difference in egg temperatures in the outer ring was just 0.6°C, suggesting that oviraptors living in warmer conditions may have exhibited a different pattern of asynchronous hatching because they could use the sun as an additional, powerful heat source.

"It's unlikely that large dinosaurs sat atop their clutches. Supposedly they used the heat of the sun or soil to hatch their eggs, like turtles. Since oviraptor clutches are open to the air, heat from the sun likely mattered much more than heat from the soil," Yang explained.

Better hatchers?

The team also investigated how oviraptor incubation efficiency compares to that of modern birds. Most birds use thermoregulatory contact incubation (TCI), where adults sit directly on the eggs to transfer heat.

TCI requires three prerequisites—the adult bird must be in contact with every egg, be the main heat source, and maintain all eggs within a constrained temperature range—which oviraptors didn't fulfill. For example, their egg arrangement prevented the adult from making full contact with all eggs in the clutch.

"Oviraptors may not have been able to conduct TCI as modern birds do," said Su. Instead, these dinosaurs and the sun may have been co-incubators—a less efficient incubation behavior than that displayed by modern birds.

Yet, the combination of adult incubation and an ambient heat source—perhaps a behavioral adaptation associated with the evolution from buried to semi-open nests—isn't necessarily worse.

"Modern birds aren't 'better' at hatching eggs. Instead, birds living today and oviraptors have a very different way of incubation or, more specifically, brooding," Yang pointed out. "Nothing is better or worse. It just depends on the environment."

• The team pointed out that their findings are specific to the reconstructed nest and are limited by the fact that today's climate does not resemble the Late Cretaceous climate, which may have impacted the results. Oviraptors also exhibited a longer incubation period than modern birds.

  Yet, the study advances our understanding of oviraptor brooding strategies through innovative approaches. It represents an important bridge between physics-based simulations and paleontological interpretations, potentially enabling paleontologists to investigate topics for which approaches were limited until now.

  "It also truly is an encouragement for all students, especially in Taiwan," concluded Yang. "There are no dinosaur fossils in Taiwan, but that does not mean that we cannot do dinosaur studies."
  
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Why a Pink Bug Hides Better Than You Think #biophotonics #biotechnology #researchawards

 A fascinating discovery by scientists reveals that a bright pink insect uses its striking color not to stand out, but to blend into its natural environment. This surprising form of camouflage helps the insect avoid predators by mimicking pink flowers or plant structures in its habitat. The study highlights how evolution can produce unexpected survival strategies, where bold colors serve as effective disguise rather than warning signals. Such findings deepen our understanding of adaptation, camouflage, and biodiversity in the natural world.

#BrightPinkInsect #Camouflage #NatureDiscovery #Evolution #Biodiversity #WildlifeScience #InsectAdaptation #NatureResearch #ScientificDiscovery #AnimalCamouflage #Ecology #BiologyNews #NatureInnovation #EnvironmentalScience #WildlifeStudy

AI Just Built a Logic Gate Inside Cells?!#biophotonics #biomedical#scienceawards #researchawards

 Researchers have developed a groundbreaking RNA-based synthetic NAND switch in living cells using artificial intelligence. This innovative genetic circuit mimics the logic of a digital NAND gate—one of the fundamental building blocks of computing—by combining two riboswitches that respond to specific molecules. The system turns gene expression off only when both molecular inputs are present, while remaining active otherwise.

#SyntheticBiology #RNAEngineering #AIBiology #GeneticCircuits #RNATechnology #Biocomputing #GeneRegulation #Bioengineering #MolecularBiology #Biotechnology #AIinBiology #Riboswitch #LivingCells #BioInnovation #SystemsBiology #GeneticSwitch #BiophotonicsResearch #NextGenBiotech #ScientificBreakthrough #FutureMedicine

Your Telomeres Are Breaking?!#scienceawards #biophotonics #researchawards

Recent discoveries show that telomere breaks—damage at the protective ends of chromosomes—can trigger chaotic chromosome mutations within cells. Telomeres normally safeguard genetic material, but when they break or become dysfunctional, chromosomes can fuse, rearrange, or shatter during cell division. This process may lead to complex genomic alterations known as chromosomal instability, which is often linked to cancer development and rapid tumor evolution. #TelomereBreaks #ChromosomeMutation #GenomicInstability #CancerResearch #Genetics #MolecularBiology #CellBiology #GenomeScience #DNARepair #BiomedicalResearch #LifeScience #ChromosomeDamage #GenomicResearch #Biotechnology #ScientificDiscovery