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Scientists are beginning to crack the fiendishly complex code that helps us to sense odours. [ABSTRACT FROM AUTHOR]

Cell biologists, including those seeking molecular mechanistic explanations of cellular phenomena, frequently rely on experimental strategies focused on identifying the cellular context relevant to their investigations. We suggest that such practices can be understood as a guided decomposition strategy, where molecular explanations of phenomena are defined in relation to natural contextual (cell) boundaries. This “top-down” strategy contrasts with “bottom-up” reductionist approaches where well-defined molecular structures and activities are orphaned by their displacement from actual biological functions. We focus on the central role of microscopic imaging in cell biology to uncover possible constraints on the system. We show how identified constraints are used heuristically to limit possible mechanistic explanations to those that are biologically meaningful. Historical examples of this process described here include discovery of the mechanism of oxidative phosphorylation in mitochondria, molecular explanation of the first steps in protein secretion, and identification of molecular motors. We suggest that these instances are examples of a form of downward causation or, more specifically, constraining relations, where higher-level structures and variables delimit and enable lower-level system states. The guided decomposition strategy in our historical cases illustrates the irreducibility of experimentally identified constraints in explaining biological activities of cells. Rather than viewing decomposition and recomposition as separate epistemic activities, we contend that they need to be iteratively integrated to account for the ontological complexity of multi-level systems. [ABSTRACT FROM AUTHOR]

How plants sense their orientation in relation to gravity and steer their root and shoot growth accordingly is not fully understood. The discovery of key steps needed for this process fills in some of the gaps in our knowledge.LAZY proteins hitchhike when roots reorient relative to gravity. [ABSTRACT FROM AUTHOR]

An unusual form of cell death called ferroptosis can sweep over embryonic tissues in a wave-like manner to ensure proper muscle development — evidence that ferroptosis has a role in normal physiology.Iron-dependent cell death sweeps across tissue to shape embryonic muscle. [ABSTRACT FROM AUTHOR]

Fluid flow at the microscale level exhibits a unique phenomenon that can be explored to fabricate microfluidic devices integrated with components that can perform various biological functions. In this manuscript, the importance of physics for microscale fluid dynamics using microfluidic devices has been reviewed. Microfluidic devices provide new opportunities with regard to spatial and temporal control over cell growth. Furthermore, the manuscript presents an overview of cellular stimuli observed by combining surfaces that mimic the complex biochemistries and different geometries of the extracellular matrix, with microfluidic channels regulating the transport of fluids, soluble factors, etc. We have also explained the concept of mechanotransduction, which defines the relation between mechanical force and biological response. Furthermore, the manipulation of cellular microenvironments by the use of microfluidic systems has been highlighted as a useful device for basic cell biology research activities. Finally, the article focuses on highly integrated microfluidic platforms that exhibit immense potential for biomedical and pharmaceutical research as robust and portable point-of-care diagnostic devices for the assessment of clinical samples. [ABSTRACT FROM AUTHOR]

A steadily growing toolbox is giving researchers the ability to monitor and measure the physical forces that shape embryonic development. [ABSTRACT FROM AUTHOR]

Fluorescent labels that have greater resistance to bleaching could help researchers to get more from biological imaging. [ABSTRACT FROM AUTHOR]

When chromosomes are lost or gained, massive changes in gene expression disrupt the delicate balance of proteins in a cell. Yeasts with incorrect chromosome numbers counteract this by degrading excess proteins.Aneuploid cells boost protein degradation to rebalance proteome. [ABSTRACT FROM AUTHOR]

Organelles called mitochondria are transferred to blood-vessel-forming cells by support cells. Unexpectedly, these mitochondria are degraded, kick-starting the production of new ones and boosting vessel formation.Mitochondrial transfer enhances endothelial-cell grafts. [ABSTRACT FROM AUTHOR]

Decades of evidence shows that exercise leads to healthier, longer lives. Researchers are just starting to work out what it does to cells to reap this reward. [ABSTRACT FROM AUTHOR]

Based on primary human cell cultures obtained from tissues of juvenile donors, bioassays to assess in vitro the biological activity of TNF-α and IL-17A inhibitors have been developed. The fibrotest-bioassay included the quantification of proinflammatory cytokines MCP-1, IL-6 and IL-8 in human foreskin fibroblasts (HFF) stimulated with TNF-α and IL-17A. The chondrotest-bioassay is based on a cartilage-derived cell culture obtained from six-fingered juvenile donors with polydactyly. Using the chondrotest-bioassay, the biological activities of the TNF-α inhibitor Remicade® (MSD, Ireland) as an original commercial drug and its biosimilar Infliximab® (BIOCAD, Russia) were compared. [ABSTRACT FROM AUTHOR]

Preclinical data show that autophagy delays age-related disease. It has been postulated that age-related disease is—at least in part—caused by an age-related decline in autophagy. However, autophagic flux has never been measured in humans across a spectrum of aging in a physiologically relevant context. To address this critical gap in knowledge, the objective of this cross-sectional observational study was to measure basal autophagic flux in whole blood taken from people at elevated risk of developing type 2 diabetes and correlate it with chronological age. During this study, 119 people were recruited and five people were excluded during sample analysis such that 114 people were included in the final analysis. Basal autophagic flux measured in blood and correlations with parameters such as age, body weight, fat mass, AUSDRISK score, blood pressure, glycated hemoglobin HbA1c, blood glucose and insulin, blood lipids, high-sensitivity C-reactive protein, plasma protein carbonylation, and plasma β-hexosaminidase activity were analysed. Despite general consensus in the literature that autophagy decreases with age, we found that basal autophagic flux increased with age in this human cohort. This is the first study to report measurement of basal autophagic flux in a human cohort and its correlation with age. This increase in basal autophagy could represent a stress response to age-related damage. These data are significant not only for their novelty but also because they will inform future clinical studies and show that measurement of basal autophagic flux in a human cohort is feasible. [ABSTRACT FROM AUTHOR]

PRR15, a member of the proline-rich protein family, has been linked to a better prognosis in breast cancer patients and is highly expressed in a variety of cancer tissues. However, further research must be done on its biological role in breast cancer and its expression. The purpose of this work is to investigate the role of PRR15 in the proliferation, migration, and apoptosis of breast cancer cells as well as to confirm the differential expression of PRR15 in various subtypes of breast cancer tissues and cells. To analyse the differential expression of PRR15 in paracancerous tissues and various types of breast cancer tissues, GEPIA, Kaplan–Meier plotter, GEO, TCGA, and other bioinformatics websites and public databases were used. PRR15 expression in breast cancer tissue was significantly higher than that in normal breast tissue, and PRR15 expression in ER + breast cancer was significantly higher than that in ER- breast cancer. The results were confirmed by RT-PCR, Western Using molecular cloning, plasmids were created to produce cells that over express PRR15. Experiments on how cells behave showed that PRR15 overexpression had no impact on the growth, migration, or death of ER+ and ER− breast cancer cells when compared to control cells. Furthermore, the biological behavior of ER + breast cancer cells was unaffected by PRR15 knockdown. Schematic Representation PRR15 expression as unique biomarker for identification of cancer expression. When compared to control cells, experiments on how cells behave revealed that PRR15 overexpression had no effect on the proliferation, migration, or death of ER+ and ER− breast cancer cells. Furthermore, PRR15 knockdown had little impact on the biological behaviour of ER+ breast cancer cells [ABSTRACT FROM AUTHOR]

With the world at their feet, these prolific young researchers are making their mark. [ABSTRACT FROM AUTHOR]

A burgeoning technique called time-resolved cryo-EM is granting insights into the tiny motors and devices that power life. [ABSTRACT FROM AUTHOR]

Direct interactions between cells in tissue are incompletely understood because the advanced technologies required to examine them are still in their infancy. A new method can decipher cell–cell interactions on a large scale.Tagging method offers versatile way to track interactions between cells. [ABSTRACT FROM AUTHOR]

Imaging and molecular manipulation reveal how biomolecular condensates form and offer clues to the role of phase separation in health and disease. [ABSTRACT FROM AUTHOR]

A new wave of research is unpicking the relationship between cancer and neurons — and looking for ways to stop the crosstalk. [ABSTRACT FROM AUTHOR]

Public participation in research, also known as citizen science, is being increasingly adopted for the analysis of biological volumetric data. Researchers working in this domain are applying online citizen science as a scalable distributed data analysis approach, with recent research demonstrating that non-experts can productively contribute to tasks such as the segmentation of organelles in volume electron microscopy data. This, alongside the growing challenge to rapidly process the large amounts of biological volumetric data now routinely produced, means there is increasing interest within the research community to apply online citizen science for the analysis of data in this context. Here, we synthesise core methodological principles and practices for applying citizen science for analysis of biological volumetric data. We collate and share the knowledge and experience of multiple research teams who have applied online citizen science for the analysis of volumetric biological data using the Zooniverse platform (www.zooniverse.org). We hope this provides inspiration and practical guidance regarding how contributor effort via online citizen science may be usefully applied in this domain. [ABSTRACT FROM AUTHOR]

Many cell biological facts that can be found in dedicated scientific textbooks are based on findings originally made in humans and/or other mammals, including respective tissue culture systems. They are often presented as if they were universally valid, neglecting that many aspects differ—in part considerably—between the three major kingdoms of multicellular eukaryotic life, comprising animals, plants and fungi. Here, we provide a comparative cross-kingdom view on the basic cell biology across these lineages, highlighting in particular essential differences in cellular structures and processes between phyla. We focus on key dissimilarities in cellular organization, e.g. regarding cell size and shape, the composition of the extracellular matrix, the types of cell–cell junctions, the presence of specific membrane-bound organelles and the organization of the cytoskeleton. We further highlight essential disparities in important cellular processes such as signal transduction, intracellular transport, cell cycle regulation, apoptosis and cytokinesis. Our comprehensive cross-kingdom comparison emphasizes overlaps but also marked differences between the major lineages of the three kingdoms and, thus, adds to a more holistic view of multicellular eukaryotic cell biology. [ABSTRACT FROM AUTHOR]

How do mitochondrial organelles remove damaged parts of inner membrane for recycling in the cytoplasm? The discovery of an exit route that flips inner membrane outside the organelle provides some answers. Pathway selectively removes inner membrane from mitochondrial organelles. [ABSTRACT FROM AUTHOR]

Cells that form tissue barriers rely on cell–cell contacts called tight junctions. These structures assemble from protein condensates that spread along the cell membrane like a water droplet spreading over glass.Step-by-step formation of tight junctions between epithelial cells. [ABSTRACT FROM AUTHOR]

Countries are grappling with how to regulate research that uses stem-cell-based embryo models. They will be watching the United Kingdom’s voluntary approach. [ABSTRACT FROM AUTHOR]

Highlights from News & Views published in early 2023. [ABSTRACT FROM AUTHOR]

Outcomes following human dense connective tissue (DCT) repair are often variable and suboptimal, resulting in compromised function and development of chronic painful degenerative diseases. Moreover, biomarkers and mechanisms that guide good clinical outcomes after DCT injuries are mostly unknown. Here, we characterize the proteomic landscape of DCT repair following human Achilles tendon rupture and its association with long-term patient-reported outcomes. Moreover, the potential regulatory mechanisms of relevant biomarkers were assessed partly by gene silencing experiments. A mass-spectrometry based proteomic approach quantified a large number (769) of proteins, including 51 differentially expressed proteins among 20 good versus 20 poor outcome patients. A novel biomarker, elongation factor-2 (eEF2) was identified as being strongly prognostic of the 1-year clinical outcome. Further bioinformatic and experimental investigation revealed that eEF2 positively regulated autophagy, cell proliferation and migration, as well as reduced cell death and apoptosis, leading to improved DCT repair and outcomes. Findings of eEF2 as novel prognostic biomarker could pave the way for new targeted treatments to improve healing outcomes after DCT injuries. Trial registration: NCT02318472 registered 17 December 2014 and NCT01317160 registered 17 March 2011, with URL and . [ABSTRACT FROM AUTHOR]

Researchers want to know why cells produce tiny packages called vesicles — and whether these bundles could be used for therapy. [ABSTRACT FROM AUTHOR]

Cryo-electron tomography is a hugely promising tool in visual proteomics — if researchers can work out what they are seeing. [ABSTRACT FROM AUTHOR]

From ancient sea species to clues on comets, papers by the country’s talented scientists are regularly making headlines. [ABSTRACT FROM AUTHOR]

Companies making cultured meat are attracting billions of dollars of investment. Here are their biggest challenges. [ABSTRACT FROM AUTHOR]

Trove of health data from space tourists and astronauts reveals the effects of microgravity, radiation and more. [ABSTRACT FROM AUTHOR]

The enzyme angiogenin functions in stress responses and aids the formation of blood vessels. It emerges that the ribosome takes a break from its usual role of making proteins to activate angiogenin and position it to cleave transfer RNA.The ribosome activates an enzyme that cleaves transfer RNA. [ABSTRACT FROM AUTHOR]

As researchers mark the loss of the first living recipient of a pig kidney, they share what they’ve learnt about xenotransplantation. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests neuroinflammation is a highly coordinated response involving multiple cell types and utilising several different forms of cellular communication. In addition to the well documented cytokine and chemokine messengers, extracellular vesicles (EVs) have emerged as key regulators of the inflammatory response. EVs act as vectors of intercellular communication, capable of travelling between different cells and tissues to deliver selectively packaged protein, miRNA, and lipids from the parent cell. During neuroinflammation, EVs transmit specific inflammatory mediators, particularly from microglia, to promote inflammatory resolution. This mini-review will highlight the novel neuroinflammatory mechanisms contributing to the biogenesis and selective packaging of EVs. [ABSTRACT FROM AUTHOR]

More than a decade ago, scientists started finding peculiar droplets inside cells. Now researchers are trying to work out how these ubiquitous beads form and what they do. [ABSTRACT FROM AUTHOR]

Cultured meat that tastes and smells more appetizing could enhance public perception of artificial steaks. [ABSTRACT FROM AUTHOR]

The protein NINJ1 drives membrane rupture associated with certain types of cell death. Investigation of NINJ1 reveals mechanistic details of how it functions, raising the possibility of developing new therapeutics.Insights into a mechanism that ruptures the plasma membrane. [ABSTRACT FROM AUTHOR]

Research on the impact of and attention given to journal covers is a crucial research topic in academia. This study investigated whether a paper featured on the cover of a journal receives more citations and higher usage than non-cover papers. Unlike previous studies that focused on just a few prestigious journals, we analyzed the citations and usage counts of 3196 cover and 36,652 non-cover papers published in 42 cell biology journals from 2011 to 2015. To address the above question, four new indicators were used to compare descriptive differences in stratified sets, and both linear regression model analysis and robustness testing were applied to further explore the relationships. Our main results showed that being a cover paper has positive and significant relationships both with citations and usage counts. Moreover, additional analyses show that the two relationships are strengthened in top-tier journals, and the main effects remain robust when we consider the influence of author ability. This new exploration of factors relevant for citations and usage counts in this empirical analysis consolidates and broadens the findings of previous studies. [ABSTRACT FROM AUTHOR]

The discovery that an evolutionarily conserved molecule used to make cholesterol also acts as a defence against a cell-death mechanism called ferroptosis might lead to new ways to treat cancer and other clinical conditions.Molecule used to make cholesterol also protects against cell death. [ABSTRACT FROM AUTHOR]

Once a plant recognizes a pathogen, part of its defence strategy is to withhold iron. The mechanism involves suppression of root acquisition of iron by degrading a molecule that activates the iron-uptake pathway. Plants attacked by bacteria degrade a protein needed for iron uptake. [ABSTRACT FROM AUTHOR]

DNA in the cytoplasm can be a sign of abnormalities such as viral infections or cancer. A protein with a role in DNA-damage response was unexpectedly found to activate defences against the threats indicated by cytoplasmic DNA. The MRN protein complex helps to activate the enzyme cGAS. [ABSTRACT FROM AUTHOR]

A suppressive type of immune cell called a regulatory T cell has a key role in helping muscles to adapt to exercise — guarding muscle mitochondrial organelles against damage mediated by proinflammatory factors generated during physical activity. Regulatory T cells protect mitochondria from damage caused by interferon. [ABSTRACT FROM AUTHOR]

Modified components of messenger RNA can cause the protein-production machinery to stall during the process of translation. This might change the protein being made, a finding with implications for vaccines or therapies. Modified mRNA component affects the fidelity of protein production. [ABSTRACT FROM AUTHOR]

The hundreds of receptors that give us our sense of smell have been found to have important roles in other parts of the body, and the prospect of targeting them with drugs is growing. [ABSTRACT FROM AUTHOR]

Lycopodina hypogea is a carnivorous sponge that tolerates laboratory husbandry very well. During a digestion cycle, performed without any digestive cavity, this species undergoes spectacular morphological changes leading to a total regression of long filaments that ensure the capture of prey and their reformation at the end of the cycle. This phenomenon is a unique opportunity to analyze the molecular and cellular determinants that ensure digestion in the sister group of all other metazoans. Using differential transcriptomic analysis coupled with cell biology studies of proliferation, differentiation, and programmed cell deaths (i.e., autophagy and the destructive/constructive function of apoptosis), we demonstrate that the molecular and cellular actors that ensure digestive homeostasis in a sister group of all remaining animals are similar in variety and complexity to those controlling tissue homeostasis in higher vertebrates. During a digestion cycle, most of these actors are finely tuned in a coordinated manner. Our data benefits from complementary approaches coupling in silico and cell biology studies and demonstrate that the nutritive function is provided by the coordination of molecular network that impacts the cells turnover in the entire organism. [ABSTRACT FROM AUTHOR]

Live-cell fluorescence spectral imaging is an evolving modality of microscopy that uses specific properties of fluorophores, such as excitation or emission spectra, to detect multiple molecules and structures in intact cells. The main challenge of analyzing live-cell fluorescence spectral imaging data is the precise quantification of fluorescent molecules despite the weak signals and high noise found when imaging living cells under non-phototoxic conditions. Beyond the optimization of fluorophores and microscopy setups, quantifying multiple fluorophores requires algorithms that separate or unmix the contributions of the numerous fluorescent signals recorded at the single pixel level. This review aims to provide both the experimental scientist and the data analyst with a straightforward description of the evolution of spectral unmixing algorithms for fluorescence live-cell imaging. We show how the initial systems of linear equations used to determine the concentration of fluorophores in a pixel progressively evolved into matrix factorization, clustering, and deep learning approaches. We outline potential future trends on combining fluorescence spectral imaging with label-free detection methods, fluorescence lifetime imaging, and deep learning image analysis. [ABSTRACT FROM AUTHOR]

Structures of the machinery for importing proteins into chloroplast organelles of algae, determined using cryo-electron microscopy, have opened a new chapter in efforts to understand how chloroplasts are built. Structure of the TOC-TIC supercomplex from algae. [ABSTRACT FROM AUTHOR]

Objectives: Air-polishing has been used in the treatment of periodontitis and gingivitis for years. The introduction of low-abrasive powders has enabled the use of air-polishing devices for subgingival therapy. Within the last decade, a wide range of different low-abrasive powders for subgingival use has been established. In this study, the effects of a glycine powder and a trehalose powder on human gingival fibroblasts (HGF) were investigated. Methods: HGF were derived from three systemically and periodontally healthy donors. After 24 h and 48 h of incubation time, mRNA levels, and after 48 h, protein levels of TNFα, IL-8, CCL2, and VEGF were determined. In addition, NF-κB p65 nuclear translocation and in vitro wound healing were assessed. Statistical analysis was performed by ANOVA and post hoc Dunnett's and Tukey's tests (p < 0.05). Results: Glycine powder significantly increased the expression of proinflammatory genes and showed exploitation of the NF-κB pathway, albeit trehalose powder hardly interfered with cell function and did not trigger the NF-κB pathway. In contrast to trehalose, glycine showed a significant inhibitory effect on the in vitro wound healing rate. Conclusion: Subgingivally applicable powders for air-polishing devices can regulate cell viability and proliferation as well as cytokine expression. Our in vitro study suggests that the above powders may influence HGF via direct cell effects. Trehalose appears to be relatively inert compared to glycine powder. Clinical relevance: With the limitations of an in vitro design, our study suggests that in terms of cell response, trehalose-based air-polishing powders show a reduced effect on inflammation. [ABSTRACT FROM AUTHOR]

This paper reports on a study which designed and developed a multi-fingered haptic interface in conjunction with a three-dimensional (3D) virtual model of a section of the cell membrane in order to enable students to work collaboratively to learn cell biology. Furthermore, the study investigated whether the addition of haptic feedback to the 3D virtual reality (VR) simulation affected learning of key concepts in nanoscale cell biology for students aged 12 to 13. The haptic interface was designed so that the haptic feedback could be turned on or switched off. Students (N = 64), in two secondary schools, worked in pairs, on activities designed to support learning of specific difficult concepts. Findings from observation of the activities and interviews revealed that students believed that being immersed in the 3D VR environment and being able to feel structures and movements within the model and work collaboratively assisted their learning. More specifically, the pilot/co-pilot model that we developed was successful for enabling collaborative learning and reducing the isolating effects of immersion with a 3D headset. Results of pre and post-tests of conceptual knowledge showed significant knowledge gains but addition of haptic feedback did not affect the knowledge gains significantly. The study enabled identification of important issues to consider when designing and using haptic-enabled 3D VR environments for collaborative learning. [ABSTRACT FROM AUTHOR]