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Although bone dehiscence may occur during orthodontic tooth movement into the narrow alveolar ridge, a non-invasive prevention method is yet to be fully established. We show for the first time prevention of bone dehiscence associated with orthodontic tooth movement by prophylactic injection of bone anabolic agents in mice. In this study, we established a bone dehiscence mouse model by applying force application and used the granular type of scaffold materials encapsulated with bone morphogenetic protein (BMP)-2 and OP3-4, the receptor activator of NF-κB ligand (RANKL)-binding peptide, for the prophylactic injection to the alveolar bone. In vivo micro-computed tomography revealed bone dehiscence with decreased buccal alveolar bone thickness and height after force application, whereas no bone dehiscence was observed with the prophylactic injection after force application, and alveolar bone thickness and height were kept at similar levels as those in the control group. Bone histomorphometry analyses revealed that both bone formation and resorption parameters were significantly higher in the injection with force application group than in the force application without the prophylactic injection group. These findings suggest that the prophylactic local delivery of bone anabolic reagents can prevent bone dehiscence with increased bone remodelling activity. [ABSTRACT FROM AUTHOR]

Bow-tie architecture is a layered network structure that has a narrow middle layer with multiple inputs and outputs. Such structures are widely seen in the molecular networks in cells, suggesting that a universal evolutionary mechanism underlies the emergence of bow-tie architecture. The previous theoretical studies have implemented evolutionary simulations of the feedforward network to satisfy a given input-output goal and proposed that the bow-tie architecture emerges when the ideal input-output relation is given as a rank-deficient matrix with mutations in network link intensities in a multiplicative manner. Here, we report that the bow-tie network inevitably appears when the link intensities representing molecular interactions are small at the initial condition of the evolutionary simulation, regardless of the rank of the goal matrix. Our dynamical system analysis clarifies the mechanisms underlying the emergence of the bow-tie structure. Further, we demonstrate that the increase in the input-output matrix reduces the width of the middle layer, resulting in the emergence of bow-tie architecture, even when evolution starts from large link intensities. Our data suggest that bow-tie architecture emerges as a side effect of evolution rather than as a result of evolutionary adaptation. [ABSTRACT FROM AUTHOR]

The cAMP‐PKA signaling pathway plays a crucial role in sensing and responding to nutrient availability in the fission yeast Schizosaccharomyces pombe. This pathway monitors external glucose levels to control cell growth and sexual differentiation. However, the temporal dynamics of the cAMP‐PKA pathway in response to external stimuli remains unclear mainly due to the lack of tools to quantitatively visualize the activity of the pathway. Here, we report the development of the kinase translocation reporter (KTR)‐based biosensor spPKA‐KTR1.0, which allows us to measure the dynamics of PKA activity in fission yeast cells. The spPKA‐KTR1.0 is derived from the transcription factor Rst2, which translocates from the nucleus to the cytoplasm upon PKA activation. We found that spPKA‐KTR1.0 translocates between the nucleus and cytoplasm in a cAMP‐PKA pathway‐dependent manner, indicating that the spPKA‐KTR1.0 is a reliable indicator of the PKA activity in fission yeast cells. In addition, we implemented a system that simultaneously visualizes and manipulates the cAMP‐PKA signaling dynamics by introducing bPAC, a photoactivatable adenylate cyclase, in combination with spPKA‐KTR1.0. This system offers an opportunity for investigating the role of the signaling dynamics of the cAMP‐PKA pathway in fission yeast cells with higher temporal resolution. Take‐away: spPKA‐KTR1.0 allows visualization of PKA activity at the single‐cell levelLive‐cell imaging reveals the transient decrease in PKA activity after M‐phaseOptogenetics allows simultaneous visualization and manipulation of PKA activity [ABSTRACT FROM AUTHOR]

O -GlcNAcylation is a dynamic modulator of signaling pathways, equal in magnitude to the widely studied phosphorylation. With the rapid development of tools for its detection at the single protein level, the O -GlcNAc modification rapidly emerged as a novel diagnostic and therapeutic target in human diseases. Yet, mapping the human O -GlcNAcome in various tissues is essential for generating relevant biomarkers. In this study, we used human banked tissue as a sample source to identify O -GlcNAcylated protein targets relevant to human diseases. Using human term placentas, we propose (1) a method to clean frozen banked tissue of blood proteins; (2) an optimized protocol for the enrichment of O -GlcNAcylated proteins using immunoaffinity purification; and (3) a bioinformatic workflow to identify the most promising O -GlcNAc targets. As a proof-of-concept, we used 45 mg of banked placental samples from two pregnancies to generate intracellular protein extracts depleted of blood protein. Then, antibody-based O -GlcNAc enrichment on denatured samples yielded over 2000 unique HexNAc PSMs and 900 unique sites using 300 μg of protein lysate. Due to efficient sample cleanup, we also captured 82 HexNAc proteins with high placental expression. Finally, we provide a bioinformatic tool (CytOVS) to sort the HexNAc proteins based on their cellular localization and extract the most promising O -GlcNAc targets to explore further. To conclude, we provide a simple 3-step workflow to generate a manageable list of O -GlcNAc proteins from human tissue and improve our understanding of O-GlcNAcylation's role in health and diseases. [ABSTRACT FROM AUTHOR]

Purpose/objectives: Tooth carvings are evaluated subjectively. However, subjective evaluations are associated with low intra‐ and inter‐evaluator reliability in providing feedback for the fabrication of better tooth carvings. Therefore, this study aimed to analyze the relationship between subjective evaluation and the morphological characteristics of tooth carvings and their morphological characteristics using the feedback method in the low‐scoring group. Methods: Between April 2013 and September 2021, 120 maxillary left first molar carvings fabricated by undergraduate students were subjectively evaluated by an experienced instructor using a five‐point scale. The tooth carvings were scanned to obtain three‐dimensional shape data and divided into two groups, the high‐ and low‐scoring groups, for principal component analysis. Homologous models with dimensions matching those of the average model were created, and principal component analysis was performed to evaluate the morphological characteristics of the tooth. Results: Principal component analysis indicated that an objective evaluation was possible using homologous model. On increasing the subjective evaluation, the occlusal inclination angle and the cervical region of the tooth became steeper, and the shape of the occlusal surface resembled a parallelogram. In addition, large morphological differences were observed in the position of the cervical region of the tooth, height of contour, and shape of the occlusal surface in the low‐scoring group, whereas no such difference was observed in the high‐scoring group. Conclusion: Objective evaluation of tooth carving was possible using homologous model. The evaluation of tooth morphological characteristics could be effective in providing feedback to undergraduate students. [ABSTRACT FROM AUTHOR]

Biomolecular condensates are broadly implicated in both normal cellular regulation and disease. Consequently, several chemical biology and optogenetic approaches have been developed to induce phase separation of a protein of interest. However, few tools are available to perform the converse function - dissolving a condensate of interest on demand. Such a tool would aid in testing whether the condensate plays specific functional roles. Here we show that light-gated recruitment of a solubilizing domain, maltose-binding protein (MBP), results in rapid and controlled dissolution of condensates formed from proteins of interest. Our optogenetic MBP-based dissolution strategy (OptoMBP) is rapid, reversible, and can be spatially controlled with subcellular precision. We also provide a proof-of-principle application of OptoMBP by disrupting condensation of the oncogenic fusion protein FUS-CHOP and reverting FUS-CHOP driven transcriptional changes. We envision that the OptoMBP system could be broadly useful for disrupting constitutive protein condensates to probe their biological functions., (© 2024. The Author(s).)

The cytoplasm is a complex, crowded environment that influences myriad cellular processes including protein folding and metabolic reactions. Recent studies have suggested that changes in the biophysical properties of the cytoplasm play a key role in cellular homeostasis and adaptation. However, it still remains unclear how cells control their cytoplasmic properties in response to environmental cues. Here, we used fission yeast spores as a model system of dormant cells to elucidate the mechanisms underlying regulation of the cytoplasmic properties. By tracking fluorescent tracer particles, we found that particle mobility decreased in spores compared to vegetative cells and rapidly increased at the onset of dormancy breaking upon glucose addition. This cytoplasmic fluidization depended on glucose-sensing via the cyclic adenosine monophosphate-protein kinase A pathway. PKA activation led to trehalose degradation through trehalase Ntp1, thereby increasing particle mobility as the amount of trehalose decreased. In contrast, the rapid cytoplasmic fluidization did not require de novo protein synthesis, cytoskeletal dynamics, or cell volume increase. Furthermore, the measurement of diffusion coefficients with tracer particles of different sizes suggests that the spore cytoplasm impedes the movement of larger protein complexes (40 to 150 nm) such as ribosomes, while allowing free diffusion of smaller molecules (~3 nm) such as second messengers and signaling proteins. Our experiments have thus uncovered a series of signaling events that enable cells to quickly fluidize the cytoplasm at the onset of dormancy breaking., Competing Interests: Competing interests statement:The authors declare no competing interest.