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Excessive exposure to sunlight, especially to ultraviolet B (UVB), results in DNA damage and a cutaneous inflammatory reaction commonly known as sunburn, which increases skin cancer risks. UVB-induced inflammasome activation in epidermal keratinocytes mediates the cutaneous inflammatory response, but the intracellular machinery that maintains skin homeostasis by suppressing UVB-induced inflammasome activation is unclear. Here, we summarize our recent work on the protective role of alternative autophagy against UVB-induced NLRP3 (NLR family pyrin domain containing 3) inflammasome activation in human keratinocytes. We found that UVB radiation induces ATG5/ATG7-independent alternative (noncanonical) autophagy, which leads to suppression of NLRP3 inflammasome activation through the clearance of damaged mitochondria in UVB-irradiated keratinocytes. Our findings indicate that ATG5/ATG7-independent alternative autophagy, rather than conventional autophagy, may play a key role in mitigating inflammatory responses, and restoring skin homeostasis after UV radiation.

Improving protein stability is important for industrial applications, and one promising method for achieving this is backbone circularization. As connector length affects stability, predicting and elucidating a more stable connector length is necessary for development of the backbone circularization method. However, the relationship between connector length and protein stability has not been completely elucidated. Here, we determined the most stable connector length for granulocyte colony‐stimulating factor by changing one residue at a time to produce connector length variants and then measuring their thermal stability. Analysis of the local structures obtained from the predicted structures of the circularized variants revealed that an approach using helix length, dihedral backbone angle, and number of unbonded hydrogen bond donors and acceptors is suitable for identifying connector lengths with higher stability.

Abstract Parkinson's disease (PD) is a common neurodegenerative disorder that results from the loss of dopaminergic neurons. Mutations in coiled‐coil‐helix‐coiled‐coil‐helix domain containing 2 (CHCHD2) gene cause a familial form of PD with α‐Synuclein aggregation, and we here identified the pathogenesis of the T61I mutation, the most common disease‐causing mutation of CHCHD2. In Neuro2a cells, CHCHD2 is in mitochondria, whereas the T61I mutant (CHCHD2T61I) is mislocalized in the cytosol. CHCHD2T61l then recruits casein kinase 1 epsilon/delta (Csnk1e/d), which phosphorylates neurofilament and α‐Synuclein, forming cytosolic aggresomes. In vivo, both Chchd2T61I knock‐in and transgenic mice display neurodegenerative phenotypes and aggresomes containing Chchd2T61I, Csnk1e/d, phospho‐α‐Synuclein, and phospho‐neurofilament in their dopaminergic neurons. Similar aggresomes were observed in a postmortem PD patient brain and dopaminergic neurons generated from patient‐derived iPS cells. Importantly, a Csnk1e/d inhibitor substantially suppressed the phosphorylation of neurofilament and α‐Synuclein. The Csnk1e/d inhibitor also suppressed the cellular damage in CHCHD2T61I‐expressing Neuro2a cells and dopaminergic neurons generated from patient‐derived iPS cells and improved the neurodegenerative phenotypes of Chchd2T61I mutant mice. These results indicate that Csnk1e/d is involved in the pathogenesis of PD caused by the CHCHD2T61I mutation.

Autophagy is a cellular mechanism that utilizes lysosomes to degrade its own components and is performed using Atg5 and other molecules originating from the endoplasmic reticulum membrane. On the other hand, we identified an alternative type of autophagy, namely, Golgi membrane-associated degradation (GOMED), which also utilizes lysosomes to degrade its own components, but does not use Atg5 originating from the Golgi membranes. The GOMED pathway involves Ulk1, Wipi3, Rab9, and other molecules, and plays crucial roles in a wide range of biological phenomena, such as the regulation of insulin secretion and neuronal maintenance. We here describe the overview of GOMED, methods to detect autophagy and GOMED, and to distinguish GOMED from autophagy.

Monoclonal antibodies have been established as the largest product class of biopharmaceuticals. Since extensive characterization is required for development and quality control of monoclonal antibody, a widely available reference material (RM) is needed. Herein, a humanized IgG1κ monoclonal antibody reference material, RM 6208-a, AIST-MAB, was established by the National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). The monoclonal antibody solution was produced as a pharmaceutical grade using a Chinese hamster ovary-derived cell line. The assigned indicative value represents the concentration of the antibody with a heterotetrameric structure including oligomeric forms, determined by an amino acid analysis using isotope dilution mass spectrometry, and their homogeneity and stability were assessed. In addition to antibody concentration, various physicochemical properties, including peptide mapping data, charge variants, and aggregates, were examined. This RM is intended for use in validation of analytical procedures and instruments such as a system suitability test for quantification of antibody. It is also intended for comparing and evaluating the results of antibody analyses across analytical methods and analytical laboratories such as inter-laboratory comparison. Both the material and the set of data from our study provide a tool for an accurate and reliable characterization of product quality attributes of monoclonal antibodies in biopharmaceutical and metrology communities.

Summary The yeast Saccharomyces cerevisiae, widely used for ethanol production, is one of the best‐understood biological systems. Diploid strains of S. cerevisiae are preferred for industrial use due to the better fermentation efficiency, in terms of vitality and endurance as compared to those of haploid strains. Whole‐genome duplications is known to promote adaptive mutations in microorganisms, and allelic variations considerably contribute to the product composition in ethanol fermentation. Although fermentation can be regulated using various strains of yeast, it is quite difficult to make fine adjustment of each component in final products. In this study, we demonstrate the use of polyploids with varying gene dosage (the number of copies of a particular gene present in a genome) in the regulation of ethanol fermentation. Ethyl caproate is one of the major flavouring agents in a Japanese alcoholic beverage called sake. A point mutation in FAS2 encoding the α subunit of fatty acid synthetase induces an increase in the amount of caproic acid, a precursor of ethyl caproate. Using the FAS2 as a model, we generated and evaluated yeast strains with varying mutant gene dosage. We demonstrated the possibility to increase mutant gene dosage via loss of heterozygosity in diploid and tetraploid strains. Productivity of ethyl caproate gradually increased with mutant gene dosage among tetraploid strains. This approach can potentially be applied to a variety of yeast strain development via growth‐based screening.

Unlike canonical macroautophagy, alternative autophagy does not require the factors Atg5 and Atg7. Here, the authors show that Wipi3 is essential for alternative autophagy, but not for canonical autophagy, and that Wipi3 functions to maintain neuronal cells via mechanisms different from those of canonical autophagy.

Unlike canonical macroautophagy, alternative autophagy does not require the factors Atg5 and Atg7, but does require Ulk1. Here the authors show that phosphorylation of Ulk1 at Ser746 by RIPK3 is required for alternative autophagy initiation at the Golgi in response to genotoxic stress.

Autophagy is an evolutionarily conserved process that degrades subcellular constituents. Mammalian cells undergo two types of autophagy; Atg5-dependent conventional autophagy and Atg5-independent alternative autophagy, and the molecules required for the latter type of autophagy are largely unknown. In this study, we analyzed the molecular mechanisms of genotoxic stress-induced alternative autophagy, and identified the essential role of p53 and damage-regulated autophagy modulator (Dram1). Dram1 was sufficient to induce alternative autophagy. In the mechanism of alternative autophagy, Dram1 functions in the closure of isolation membranes downstream of p53. These findings indicate that Dram1 plays a pivotal role in genotoxic stress-induced alternative autophagy.

This article presented the data related to the research article entitled “Calibration-free concentration analysis for an analyte prone to self-association” (H. Imamura, S. Honda, 2017) [1]. The data included surface plasmon resonance (SPR) responses of the variants of protein G with different masses under mass transport limitation. The friction factors of the proteins analyzed by an ultracentrifugation were recorded. Calculation of the SPR response of the proteins was also described.

In press processing, quality inspection of a product is often carried out for each lot in the post process stage. When a failure occurs, it may result in a large number of defective products due to the fast processing speed. In order to prevent this, it is ideal to immediately stop the processing just after the defect occurs. Therefore, confirming the processing state in-process is required. This study proposes a new quality inspection method for deep drawing processes by using the count rate of acoustic emission (AE) signals. To analyze the AE count, deep learning, which is a multilayered neural network, is employed to recognize defects during a deep drawing process. The material used was a ductile material of cold rolled steel plate and is relatively difficult to find cracks during the deep drawing process. Characteristics were clarified by analysis of AE counts at plastic deformation and brake of material, and performing the forming state recognition experiment by a multilayer neural network (deep learning) showed a maximum recognition rate of 97.3%. High recognition rate was obtained despite the small number of data used.

The ubiquitin-proteasome system is thought to be the primary regulator of centrosome number. Here, Watanabe et al. show that selective autophagy also plays a role in regulating centrosome number via p62-dependent recruitment of centrosomal protein 63 to autophagosomes.

The present paper proposes a multi-objective optimization technique for smart laminated composites to maximize two conflicting objectives. The first objective is the performance of active vibration control of smart composite with piezoelectric (PZT) actuators. The second is the fundamental frequency of smart structures related to the performance of passive vibration control. Both performances of active and passive vibration control are maximized simultaneously. The vibration suppression of smart structures strongly depends on both actuator placements and vibration mode shapes. It is possible to design vibration mode shapes for laminated fibrous composites since their anisotropy for whole thickness is tailorable by arranging fiber orientation angle in each layer. This allows the smart structure with laminated composite to archive higher performance of vibration suppression than those with isotropic materials. However, the optimized structure results in lower natural frequencies than composites with typical fiber orientation angles since an effective input of control force from actuators is realized for the structure with lower stiffness. This reveals that there is a trade-off relation for smart composite structures between the performance of active vibration suppression and natural frequencies. To disclose this relation, the present study applies the effective multi-objective optimization technique, the refined non-dominated genetic algorithm (NSGAII), and obtains Pareto optimal solutions. Calculated results are successfully validated by a comparison with those from the real-time control experiment where a laser excitation technique which is effective to small sized structures is used.

During fabrication process of laminated fibrous composites, asymmetric laminates result in skewed surfaces after curing due to strong anisotropy of each layer, and composites with specific lay-ups and dimensions show bi-stable states in terms of surface shapes. The present study performs a multi-objective optimization for the composite shell with bi-stable shapes. Objective functions are amount of averaged deformation between two stable shapes of shell (snap-thorough deformation) and critical temperature of surroundings which is the maximum temperature to keep the bi-stable characteristics. These properties indicate a trade-off relation each other and are maximized simultaneously by using an effective multi-objective genetic algorithm method, SPEA+. Shell shapes after curing are predicted by the thermal deformation analysis based on the Rayleigh-Ritz method with directly assumed strain functions. Calculated results agree well with those from experiments with respect to shell shapes, and the present multi-objective optimization reveals wide-ranging Pareto optimum solutions. The numerical results show that spirally laminated fiber orientation angles are effective to increase amount of snap-thorough deformation.

Dynamic Partial Reconfiguration technology coupled with an Operating System for Reconfigurable Systems (OS4RS) allows for implementation of a hardware task concept, that is, an active computing object which can contend for reconfigurable computing resources and request OS services in a way software task does in a conventional OS. In this work, we show a complete model and implementation of a lightweight OS4RS supporting preemptable and clock-scalable hardware tasks. We also propose a novel, lightweight scheduling mechanism allowing for timely and priority-based reservation of reconfigurable resources, which aims at usage of preemption only at the time it brings benefits to the performance of a system. The architecture of the scheduler and the way it schedules allocations of the hardware tasks result in shorter latency of system calls, thereby reducing the overall OS overhead. Finally, we present a novel model and implementation of a channel-based intertask communication and synchronization suitable for software-hardware multitasking with preemptable and clock-scalable hardware tasks. It allows for optimizations of the communication on per task basis and utilizes point-to-point message passing rather than shared-memory communication, whenever it is possible. Extensive overhead tests of the OS4RS services as well as application speedup tests show efficiency of our approach.

Fatty acids and isoprenoids can be covalently attached to a variety of proteins. These lipid modifications regulate protein structure, localization and function. Here, we describe a yeast one-hybrid approach based on the Gγ recruitment system that is useful for identifying sequence motifs those influence lipid modification to recruit proteins to the plasma membrane. Our approach facilitates the isolation of yeast cells expressing lipid-modified proteins via a simple and easy growth selection assay utilizing G-protein signaling that induces diploid formation. In the current study, we selected the N-terminal sequence of Gα subunits as a model case to investigate dual lipid modification, i.e., myristoylation and palmitoylation, a modification that is widely conserved from yeast to higher eukaryotes. Our results suggest that both lipid modifications are required for restoration of G-protein signaling. Although we could not differentiate between myristoylation and palmitoylation, N-terminal position 7 and 8 play some critical role. Moreover, we tested the preference for specific amino-acid residues at position 7 and 8 using library-based screening. This new approach will be useful to explore protein-lipid associations and to determine the corresponding sequence motifs.