Search

We investigated the electronic and magnetic properties of fully oxidized BaFeO3 thin films, which show ferromagnetic-insulating properties with cubic crystal structure, by hard x-ray photoemission spectroscopy (HAXPES), x-ray absorption spectroscopy (XAS), and soft x-ray magnetic circular dichroism (XMCD). We analyzed the results with configuration-interaction (CI) cluster-model calculations for Fe4+, which showed good agreement with the experimental results. We also studied SrFeO3 thin films, which have an Fe4+ ion helical magnetism in cubic crystal structure, but are metallic at all temperatures. We found that BaFeO3 thin films are insulating with large magnetization (1.7 µB/formula unit) under ~1 T, using valence-band HAXPES and Fe 2p XMCD, which is consistent with the previously reported resistivity and magnetization measurements. Although Fe 2p core-level HAXPES and Fe 2p XAS spectra of BaFeO3 and SrFeO3 thin films are quite similar, we compared the insulating BaFeO3 to metallic SrFeO3 thin films with valence-band HAXPES. The CI cluster-model analysis indicates that the ground state of BaFeO3 is dominated by d5L(L: ligand hole) configuration due to the negative charge transfer energy, and that the band gap has significant O 2p character. We revealed that the differences of the electronic and magnetic properties between BaFeO3 and SrFeO3 arise from the differences in their lattice constants, through affecting the strength of hybridization and bandwidth. [ABSTRACT FROM AUTHOR]

Abstract Background For the establishment of functional neural circuits that support a wide range of animal behaviors, initial circuits formed in early development have to be reorganized. One way to achieve this is local remodeling of the circuitry hardwiring. To genetically investigate the underlying mechanisms of this remodeling, one model system employs a major group of Drosophila multidendritic sensory neurons - the dendritic arborization (da) neurons - which exhibit dramatic dendritic pruning and subsequent growth during metamorphosis. The 15 da neurons are identified in each larval abdominal hemisegment and are classified into four categories - classes I to IV - in order of increasing size of their receptive fields and/or arbor complexity at the mature larval stage. Our knowledge regarding the anatomy and developmental basis of adult da neurons is still fragmentary. Results We identified multidendritic neurons in the adult Drosophila abdomen, visualized the dendritic arbors of the individual neurons, and traced the origins of those cells back to the larval stage. There were six da neurons in abdominal hemisegment 3 or 4 (A3/4) of the pharate adult and the adult just after eclosion, five of which were persistent larval da neurons. We quantitatively analyzed dendritic arbors of three of the six adult neurons and examined expression in the pharate adult of key transcription factors that result in the larval class-selective dendritic morphologies. The 'baseline design' of A3/4 in the adult was further modified in a segment-dependent and age-dependent manner. One of our notable findings is that a larval class I neuron, ddaE, completed dendritic remodeling in A2 to A4 and then underwent caspase-dependent cell death within 1 week after eclosion, while homologous neurons in A5 and in more posterior segments degenerated at pupal stages. Another finding is that the dendritic arbor of a class IV neuron, v'ada, was immediately reshaped during post-eclosion growth. It exhibited prominent radial-to-lattice transformation in 1-day-old adults, and the resultant lattice-shaped arbor persisted throughout adult life. Conclusion Our study provides the basis on which we can investigate the genetic programs controlling dendritic remodeling and programmed cell death of adult neurons, and the life-long maintenance of dendritic arbors.

Using resonant soft-x-ray scattering as a function of both temperature and magnetic field, we reveal a large number of almost degenerate magnetic orders in SrCo6O11. The Ising-like spins in this frustrated material in fact exhibit a so-called magnetic devil's staircase. It is demonstrated how a magnetic field induces transitions between different microscopic spin configurations, which is responsible for the magnetoresistance of SrCo6O11. This material therefore constitutes a unique combination of a magnetic devil's staircase and spin-valve effects, yielding a novel type of magnetoresistance system. [ABSTRACT FROM AUTHOR]

Type 2 diabetes is a chronic disease marked by hyperglycemia; impaired insulin secretion by pancreatic β-cells is a hallmark of this disease. Recent studies have shown that hypoxia occurs in the β-cells of patients with type 2 diabetes and hypoxia, in turn, contributes to the insulin secretion defect and β-cell loss through various mechanisms, including the activation of hypoxia-inducible factors, induction of transcriptional repressors, and activation of AMP-activated protein kinase. This review focuses on advances in our understanding of the contribution of β-cell hypoxia to the development of β-cell dysfunction in type 2 diabetes. A better understanding of β-cell hypoxia might be useful in the development of new strategies for treating type 2 diabetes.

The initiation of DNA replication is tightly controlled by the licensing system that loads replicative DNA helicases onto replication origins to form pre-replicative complexes (pre-RCs) once per cell cycle. Cdc10-dependent transcript 1 (Cdt1) plays an essential role in the licensing reaction by recruiting mini-chromosome maintenance (MCM) complexes, which are eukaryotic replicative DNA helicases, to their origins via direct protein-protein interactions. Cdt1 interacts with other pre-RC components, the origin recognition complex, and the cell division cycle 6 (Cdc6) protein; however, the molecular mechanism by which Cdt1 functions in the MCM complex loading process has not been fully elucidated. Here, we analyzed the protein-protein interactions of recombinant Cdt1 and observed that Cdt1 self-associates via the central region of the molecule, which is inhibited by the endogenous licensing inhibitor, geminin. Mutation of two β-strands of the winged-helix domain in the central region of Cdt1 attenuated its self-association but could still interact with other pre-RC components and DNA similarly to wild-type Cdt1. Moreover, the Cdt1 mutant showed decreased licensing activity in Xenopus egg extracts. Together, these results suggest that the self-association of Cdt1 is crucial for licensing.

Premise: Insect defoliation of trees causes unusual changes to wood anatomy and slows radial growth that decreases tree value; however, the characteristics of these anatomical changes in hardwoods remain unclear. The aim of this study was to characterize the anatomy and histochemistry of the wood in trunks of Betula maximowicziana trees after severe insect defoliation., Methods: Secondary xylem tissues were sampled from trunks that had been defoliated by Caligula japonica at Naie and Furano in central Hokkaido during 2006-2012, then cross-dated and examined microscopically and stained histochemically to characterize anatomical and chemical changes in the cells., Results: White rings with thin-walled wood fibers and greatly reduced annual ring width in the subsequent year were observed in samples from both sites. From these results, the year that the white rings formed was determined, and severe defoliation was confirmed to trigger white ring formation. The characteristics may prove useful to detect the formation year of white rings. Scanning electron microscopy and histochemical analyses of the white rings indicated that the thickness of the S 2 layer in the wall of wood fiber cells decreased, but xylan and lignin were still deposited in the cell walls of wood fibers. However, the walls of the fibers rethickened after the defoliation., Conclusions: Our results suggest that B. maximowicziana responds to a temporary lack of carbon inputs due to insect defoliation by regulating the thickness of the S 2 layer of the cell wall of wood fibers. For B. maximowicziana, insect defoliation late in the growing season has serious deleterious effects on wood formation and radial growth., (© 2023 Botanical Society of America.)

Vascular bundles of bamboo are determinants for mechanical properties of bamboo material and for physiological properties of living bamboo. The morphology of vascular bundles reflecting mechanical and physiological functions differs not only within internode tissue but also among different internodes in the culm. Although the distribution of vascular bundle fibers has received much attention, quantitative evaluation of the morphological transformation of vascular bundles associated with spatial distribution patterns has been limited. In this study deep learning models were used to determine quantitative changes in the distribution and morphology of vascular bundles in the culms of moso bamboo (Phyllostachys pubescens). A precise model for extracting vascular bundles from cross-sectional images was constructed using the U-Net model. Analyses of extracted vascular bundles from different internodes showed significant changes in vascular bundle distribution and morphology among internodes. Vascular bundles in lower internodes showed outer relative position and larger area than those in upper internodes. Aspect ratio and eccentricity indicate that vascular bundles in internodes near the base have more elliptical morphology, with a long axis in the radial direction. The variational autoencoder model using extracted vascular bundles enabled simulation of the morphological transformation of vascular bundles along with radial direction. These deep learning models enabled highly accurate quantification of vascular bundle morphologies, and will contribute to a further understanding of bamboo development as well as evaluation of the mechanical and physiological properties of bamboo., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Tsuyama et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Hypoxia can occur in pancreatic β-cells in type 2 diabetes. Although hypoxia exerts deleterious effects on β-cell function, the associated mechanisms are largely unknown. Here, we show that the transcriptional repressor basic helix-loop-helix family member e40 (BHLHE40) is highly induced in hypoxic mouse and human β-cells and suppresses insulin secretion. Conversely, BHLHE40 deficiency in hypoxic MIN6 cells or β-cells of ob/ob mice reverses defects in insulin secretion. Mechanistically, BHLHE40 represses the expression of Mafa, encoding the transcription factor musculoaponeurotic fibrosarcoma oncogene family A (MAFA), by attenuating the binding of pancreas/duodenum homeobox protein 1 (PDX1) to its enhancer region. Impaired insulin secretion in hypoxic β-cells was recovered by MAFA re-expression. Collectively, our work identifies BHLHE40 as a key hypoxia-induced transcriptional repressor in β-cells that inhibit insulin secretion by suppressing MAFA expression., (© 2023 The Authors.)

Adipose tissue is a central organ for controlling systemic metabolism both in invertebrates and vertebrates. Here, we have investigated the developmental processes of the adult-type fat body (AFB) in Drosophila. We have established genetic tools that allow visualization and genetic manipulations of cells in the AFB lineage from early in metamorphosis. We identified precursor cells that give rise to the AFB and delineated dynamic cellular behaviors underlying AFB formation. These precursor cells displayed polarized cell shapes and oriented motility, with emigration from the thorax and subsequent dispersal to the abdomen and head. After the migration period, these cells adhered to each other, assembling into the AFB with a sheet-like architecture. Continuous cell proliferation occurred during and after the large-scale migration to achieve appropriate fat tissue mass. Homotypic cell fusion after the sheet formation contributed to the establishment of multinucleated cells in the AFB. We also examined candidate gene functions, and our results argue that ecdysone signaling and the transcription factor Serpent support adult fat body organogenesis., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)

Termitomyces sp. that grow in symbiosis with fungus-farming Termites have medicinal properties. However, they are rare in nature, and their artificial culture is challenging. The expression of AXL receptor tyrosine kinase and immune checkpoint molecules favor the growth of cancer cells. The study evaluated the optimal conditions for the artificial culture of Termitomyces and their inhibitory activity on AXL and immune checkpoint molecules in lung adenocarcinoma and melanoma cell lines. The culture of 45 strains of Termitomyces was compared. Five strains with marked growth rates were selected. Four of the selected strains form a single cluster by sequence analysis. The mycelium of 4 selected strains produces more fungal mass in potato dextrose broth than in a mixed media. The bark was the most appropriate solid substrate for Termitomyces mycelia culture. The mycelium of all five selected strains showed a higher growth rate under normal CO 2 conditions. The culture broth, methanol, and ethyl acetate of one selected strain (T-120) inhibited the mRNA relative expression of AXL receptor tyrosine kinase and immune checkpoint molecules in cancer cell lines. Overall, these results suggest the potential usefulness of Termitomyces extracts as a co-adjuvant therapy in malignant diseases., Competing Interests: E.C.G. and I.K. have a pending patent on the discovery reported in this article. Other authors declared no conflict of interest regarding this work., (© 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the Korean Society of Mycology.)

Wood biomass conversion for fossil resource replacement could result in the sustainable production of chemicals, although lignin represents an obstacle to efficient polysaccharide use. White-rot fungus Phlebia sp. MG-60 reportedly selectively and aerobically degrades lignin in hardwood, then it begins cellulose saccharification from the delignified wood to produce ethanol. Environmental conditions might change white-rot fungi-driven biomass conversion. However, how the environmental response sensor affects ethanol fermentation in white-rot fungi remains elusive. In this study, we focused on MGHOG1, the yeast Hog1 homolog in Phlebia sp. MG-60, a presumably important player in osmoresponse. We generated MGHOG1 overexpressing (OE) transformants in Phlebia sp. MG-60, exhibiting slower mycelial growth compared with the wild-type under salinity stress. MGHOG1 overexpressing liquid cultures displayed suppressed mycelial growth and ethanol fermentation. Therefore, MGHOG1 potentially influences ethanol fermentation and mycelial growth in Phlebia sp. MG-60. This study provides novel insights into the regulation of white-rot fungi-mediated biomass conversion., (© Crown copyright 2023.)

Brown adipose tissue plays a central role in the regulation of the energy balance by expending energy to produce heat. NAD + -dependent deacylase sirtuins have widely been recognized as positive regulators of brown adipose tissue thermogenesis. However, here we reveal that SIRT7, one of seven mammalian sirtuins, suppresses energy expenditure and thermogenesis by regulating brown adipose tissue functions. Whole-body and brown adipose tissue-specific Sirt7 knockout mice have higher body temperature and energy expenditure. SIRT7 deficiency increases the protein level of UCP1, a key regulator of brown adipose tissue thermogenesis. Mechanistically, we found that SIRT7 deacetylates insulin-like growth factor 2 mRNA-binding protein 2, an RNA-binding protein that inhibits the translation of Ucp1 mRNA, thereby enhancing its inhibitory action on Ucp1. Furthermore, SIRT7 attenuates the expression of batokine genes, such as fibroblast growth factor 21. In conclusion, we propose that SIRT7 serves as an energy-saving factor by suppressing brown adipose tissue functions., (© 2022. The Author(s).)

Sirtuins (SIRT1-7 in mammals) are evolutionarily conserved nicotinamide adenine dinucleotide-dependent lysine deacetylases/deacylases that regulate fundamental biological processes including aging. In this study, we reveal that male Sirt7 knockout (KO) mice exhibited an extension of mean and maximum lifespan and a delay in the age-associated mortality rate. In addition, aged male Sirt7 KO mice displayed better glucose tolerance with improved insulin sensitivity compared with wild-type (WT) mice. Fibroblast growth factor 21 (FGF21) enhances insulin sensitivity and extends lifespan when it is overexpressed. Serum levels of FGF21 were markedly decreased with aging in WT mice. In contrast, this decrease was suppressed in Sirt7 KO mice, and the serum FGF21 levels of aged male Sirt7 KO mice were higher than those of WT mice. Activating transcription factor 4 (ATF4) stimulates Fgf21 transcription, and the hepatic levels of Atf4 mRNA were increased in aged male Sirt7 KO mice compared with WT mice. Our findings indicate that the loss of SIRT7 extends lifespan and improves glucose metabolism in male mice. High serum FGF21 levels might be involved in the beneficial effect of SIRT7 deficiency.

Main Conclusion: The feruloylarabinoxylan deposition was initiated at the formation of the secondary cell wall, especially S 2 layer in moso bamboo, which may affect crosslinking between cell wall components and plant growth. Hemicelluloses, major components of plant cell walls that are hydrogen bonded to cellulose and covalently bound to lignin, are crucial determinants of cell wall properties. Especially in commelinid monocotyledons, arabinoxylan is often esterified with ferulic acid, which is essential to crosslinking with cell wall components. However, the deposition patterns and localization of ferulic acid during cell wall formation remain unclear. In this study, developing moso bamboo (Phyllostachys pubescens) culms were used to elucidate deposition patterns of hemicelluloses including feruloylarabinoxylan. Ferulic acid content peaked with cessation of elongation growth, and thereafter decreased and remained stable as culm development proceeded. During primary cell wall (PCW) formation, xyloglucan and (1,3;1,4)-β-glucan signals were detected in all tissues. Along with culm development, arabinoxylan and feruloylarabinoxylan signals were sequentially observed in the protoxylem, vascular fibers and metaxylem, and parenchyma. Feruloylarabinoxylan signals were observed slightly later than arabinoxylan signals. Arabinoxylan signals were observed throughout the compound middle lamella and secondary cell wall (SCW), whereas the feruloylarabinoxylan signal was localized to the S 2 layer of the SCW. These results indicate that the biosynthesis of hemicelluloses is regulated in accordance with cell wall layers. Feruloylarabinoxylan deposition may be initiated at the formation of SCW, especially S 2 layer formation. Ferulic acid-mediated linkages of arabinoxylan-arabinoxylan and arabinoxylan-lignin would arise during SCW formation with the cessation of elongation growth., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Pluripotent stem cells (PSCs) exhibit a unique feature that requires S-adenosylmethionine (SAM) for the maintenance of their pluripotency. Methionine deprivation in the medium causes a reduction in intracellular SAM, thus rendering PSCs in a state potentiated for differentiation. In this study, we find that methionine deprivation triggers a reduction in intracellular protein-bound Zn content and upregulation of Zn exporter SLC30A1 in PSCs. Culturing PSCs in Zn-deprived medium results in decreased intracellular protein-bound Zn content, reduced cell growth, and potentiated differentiation, which partially mimics methionine deprivation. PSCs cultured under Zn deprivation exhibit an altered methionine metabolism-related metabolite profile. We conclude that methionine deprivation potentiates differentiation partly by lowering cellular Zn content. We establish a protocol to generate functional pancreatic β cells by applying methionine and Zn deprivation. Our results reveal a link between Zn signaling and methionine metabolism in the regulation of cell fate in PSCs., Competing Interests: Declaration of interests A part of the research was conducted with a research fund from Ajinomoto. A.A., H.O., and M.Y. are salaried employees of Ajinomoto. A part of the research is related to a patent that is pending., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Calreticulin (CRT), a chaperone typically located in the endoplasmic reticulum (ER), is known to translocate to the cell surface in response to anticancer drugs. Cell surface CRT (ecto-CRT) on apoptotic or pre-apoptotic cells serves as an "eat me" signal that can promote phagocytosis. In this study, we observed the biphasic (early transient and late sustained) increase of ecto-CRT on HT-29 cells after treatment with oxaliplatin (L-OHP). To investigate the role of ecto-CRT that accumulates in the early and late phases as "eat me" signals, we examined the phagocytosis of HT-29 cells by macrophage-like cells and dendritic cell (DC) -like cells prepared from THP-1 cells. The results indicated that the early ecto-CRT-expressed cells were phagocytosed by immature DC-like cells, and the late ecto-CRT-expressed cells were phagocytosed primarily by macrophage-like cells, while mature DC-like cells did not respond to the either class of ecto-CRT-expressed cells. Both types of phagocytotic events were inhibited by CRT Blocking Peptide, suggesting that such events depended on the ecto-CRT. Our results suggested that the early increase of ecto-CRT is related to phagocytosis as part of immunogenic cell death (ICD), while the late increase of ecto-CRT is related to the removal of apoptotic cells by macrophages., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Introduction: We previously developed a novel methylation assay, the combined restriction digital PCR (CORD) assay, consisting of treatment of DNA with methylation-sensitive restriction enzymes and droplet digital PCR., Methods: In this study, we assessed the diagnostic performance of serum methylated Homeobox A1 (mHOXA1) and methylated somatostatin (mSST) using the CORD assay in combination with CA19-9 for pancreatic cancer using serum samples from 82 healthy individuals, 13 patients with benign pancreatic disease, 3 patients with branched-duct intraductal papillary mucinous neoplasm, and 91 patients with pancreatic cancer., Results: For the single marker tests, sensitivity for all stages of pancreatic cancer, stage I cancer, and specificity were, respectively, 71.4%, 50.0%, and 94.9% for CA19-9; 51.6%, 68.8%, and 90.8% for mHOXA1; and 50.1%, 68.8%, and 94.9% for mSST. Those for the combined marker tests were, respectively, 86.8%, 81.3%, and 85.7% for combined mHOXA1 and CA19-9; 86.8%, 87.5%, and 89.8% for combined mSST and CA19-9; and 89.0%, 87.5%, and 85.7% for all three markers combined., Conclusion: The combination of mHOXA1 and mSST with CA19-9 appears to be useful to detect pancreatic cancer even at an early stage., (© 2022 S. Karger AG, Basel.)

Cell walls, especially secondary cell walls (SCWs), maintain cell shape and reinforce wood, but their structure and shape can be altered in response to gravity. In hardwood trees, tension wood is formed along the upper side of a bending stem and contains wood fiber cells that have a gelatinous layer (G-layer) inside the SCW. In a previous study, we generated nst/snd quadruple-knockout aspens (Populus tremula × Populus tremuloides), in which SCW formation was impaired in 99% of the wood fiber cells. In the present study, we produced nst/snd triple-knockout aspens, in which a large number of wood fibers had thinner SCWs than the wild type (WT) and some had no SCW. Because SCW layers are always formed prior to G-layer deposition, the nst/snd mutants raise interesting questions of whether the mutants can form G-layers without SCW and whether they can control their postures in response to changes in gravitational direction. The nst/snd mutants and the WT plants showed growth eccentricity and vessel frequency reduction when grown on an incline, but the triple mutants recovered their upright growth only slightly, and the quadruple mutants were unable to maintain their postures. The mutants clearly showed that the G-layers were formed in SCW-containing wood fibers but not in those lacking the SCW. Our results indicate that SCWs are essential for G-layer formation and posture control. Furthermore, each wood fiber cell may be able to recognize its cell wall developmental stage to initiate the formation of the G-layer as a response to gravistimulation., (© 2021 Society for Experimental Biology and John Wiley & Sons Ltd.)

Lignin is the second most abundant natural polymer on Earth and is a major cell wall component in vascular plants. Lignin biosynthesis has three stages: biosynthesis, transport, and polymerization of its precursors. However, there is limited knowledge on lignin precursor transport, especially in monocots. In the present study, we aimed to elucidate the transport mode of lignin monomers in the lignifying tissues of bamboo ( Phyllostachys pubescens ). The growth manners and lignification processes of bamboo shoots were elucidated, which enabled us to obtain the lignifying tissues reproducibly. Microsomal membrane fractions were prepared from tissues undergoing vigorous lignification to analyze the transport activities of lignin precursors in order to show the ATP-dependent transport of coniferin and p -glucocoumaryl alcohol. The transport activities for both precursors depend on vacuolar type H + -ATPase and a H + gradient across the membrane, suggesting that the electrochemical potential is the driving force of the transport of both substrates. These findings are similar to the transport properties of these lignin precursors in the differentiating xylem of poplar and Japanese cypress. Our findings suggest that transport of coniferin and p -glucocoumaryl alcohol is mediated by secondary active transporters energized partly by the vacuolar type H + -ATPase, which is common in lignifying tissues. The loading of these lignin precursors into endomembrane compartments may contribute to lignification in vascular plants.

Aims/introduction: Peroxisome proliferator-activated receptor (PPAR)-γ2 is a transcription factor crucial for regulating adipogenesis and glucose/lipid metabolism, and synthetic PPARγ ligands, such as thiazolidinediones, are effective oral medication for type 2 diabetes. Sirtuin 7 (SIRT7), a nicotinamide adenine dinucleotide-dependent deacetylase, also controls metabolism. However, it is not known whether SIRT7 regulates the function of PPARγ2 by its deacetylation., Materials and Methods: Physical interaction between SIRT7 and PPARγ2, the effect of SIRT7 on PPARγ2 acetylation, and the deacetylation residue targeted by SIRT7 were investigated. The effects of PPARγ2 K382 acetylation on lipid accumulation, gene expression in C3H10T1/2 cell-derived adipocytes, and ligand-dependent transactivation activity were also evaluated., Results: We demonstrated that SIRT7 binds to PPARγ2 and deacetylates PPARγ2 at K382. C3H10T1/2-derived adipocytes expressing PPARγ2 K382Q (a mimic of acetylated K) accumulated much less fat than adipocytes expressing wild-type PPARγ2 or PPARγ2 K382R (a mimic of nonacetylated K). Global gene expression analysis of adipocytes expressing PPARγ2 K382Q revealed that K382Q caused the dysregulation of a set of genes involved in lipogenesis, including Srebp1c, Acaca, Fasn, and Scd1. The rosiglitazone-dependent transcriptional activity of PPARγ2 K382Q was reduced compared with that of PPARγ2 K382R ., Conclusion: Our findings indicate that SIRT7-dependent PPARγ2 deacetylation at K382 controls lipogenesis in adipocytes., (© 2021 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.)

Competing Interests: None

RecQ4, a member of the RecQ helicase family, is required for the maintenance of genome integrity. RecQ4 has been shown to promote the following two DNA double-strand break (DSB) repair pathways: non-homologous end joining (NHEJ) and homologous recombination (HR). However, its molecular function has not been fully elucidated. In the present study, we aimed to investigate the role of RecQ4 in NHEJ using Xenopus egg extracts. The N-terminal 598 amino acid region of Xenopus RecQ4 (N598), which lacks a central helicase domain and a downstream C-terminal region, was added to the extracts and its effect on the joining of DNA ends was analyzed. We found that N598 inhibited the joining of linearized DNA ends in the extracts. In addition, N598 inhibited DSB-induced chromatin binding of Ku70, which is essential for NHEJ, while the DSB-induced chromatin binding of the HR-associated proteins, replication protein A (RPA) and Rad51, increased upon the addition of N598. These results suggest that RecQ4 possibly influences the choice of the DSB repair pathway by influencing the association of the Ku heterodimer with the DNA ends., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Aims: The current study aimed to assess the validity and internal consistency of a 20-item checklist to help provide rehabilitation based on effective and clear goal setting., Methods: A questionnaire survey was conducted regarding rehabilitation practices followed by physical, occupational, and speech-language therapists over the past month. The questionnaire was based on a checklist covering the following four areas, each comprising five items: goal setting based on patient and family intent and therapist perspective including long-term and short-term goals; therapist's specialized analysis and focalization of problems using the International Classification of Functioning, Disability and Health to clarify work processes and behaviors that hinder high-priority activities; proposal of plans considering the evidence and environment, which clarifies options for resolution methods (plans) and evidence; and formulation and implementation of plans including patient and family intent, which determines plan frequency and implementation period. The checklist was prepared based on medical records and previous studies by two occupational therapists who had experience in providing hospital and home-visit rehabilitation. To test the factorial validity of the 20-item checklist, confirmatory factor analysis was performed, and Cronbach's α coefficients were calculated., Results: The participants' mean age was 28 (25-75th percentile, range: 25-32) years. Of the 385 participants, 163 were home-visit rehabilitation therapists. Our model revealed a fair fit to data (χ2 statistic = 602.0) and standardized path coefficients ranged from 0.67 to 0.95. Path coefficients were at least 0.41 for all 20 items. Cronbach's α for goal setting, problem analysis, problem solving method proposals, and formulation and implementation of specific plans were 0.896, 0.890, 0.935, and 0.925, respectively., Conclusion: Based on the assessment of therapists' practice over 1 month using the developed checklist, the factorial validity and internal consistency of these checklist items were considered acceptable. Education based on these checklist items might support goal setting and planning and improve patient outcomes., (Copyright © 2021 JBI. Unauthorized reproduction of this article is prohibited.)

Hepatocyte nuclear factor 1α (HNF1α) is a transcription factor required for normal insulin secretion and maintenance of β-cell number in the pancreas. HNF1α is also expressed in pancreatic α-cells, but its role in these cells is unknown. The aim of this study was to clarify the role of HNF1α in α-cells. Male Hnf1a+/- mice with a mixed background were backcrossed to outbred ICR mice. Glucose tolerance, glucagon and insulin secretion, islet histology, and gene expression were investigated in ICR Hnf1a-/- and Hnf1a+/+ mice. Regulation of Slc5a1 (encoding sodium glucose cotransporter 1 [SGLT1]) expression by HNF1α and the effect of SGLT1 inhibition on glucagon secretion were also explored. ICR Hnf1a-/- mice were glucose intolerant and exhibited impaired glucose-stimulated insulin secretion. The β-cell area of ICR mice was decreased in Hnf1a-/- mice, but the α-cell area in the pancreas was similar between Hnf1a-/- and Hnf1a+/+ mice. Hnf1a-/- mice showed higher fasting glucagon levels and exhibited inadequate suppression of glucagon after glucose load. In addition, glucagon release in response to hypoglycemia was impaired in Hnf1a-/- mice, and glucagon secretion after 1.1 mM glucose administration, was also decreased in Hnf1a-/- islets. Slc5a1 expression was decreased in Hnf1a-/- islets, while HNF1α activated the Slc5a1 promoter in αTC1-6 cells. Inhibition of SGLT1 suppressed 1.1 mM glucose-stimulated glucagon secretion in islets and αTC1-6 cells, but SGLT1 inhibition had no additional inhibitory effect in HNF1α-deficient cells. Our findings indicate that HNF1α modulates glucagon secretion in α-cells through the regulation of Slc5a1., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Recent evidence has revealed a novel signaling mechanism through which brown adipose tissue (BAT)-derived exosomal microRNAs (miRNAs) influence hepatic gene expression. Here, we uncover neuronal control of these miRNAs and identify exosomal miR-132-3p as a regulator of hepatic lipogenesis under cold stress conditions. Norepinephrine, a sympathetic nervous system neurotransmitter mediating cold-induced BAT activation, altered the composition of brown adipocyte (BAC)-derived exosomal miRNAs; among them, miR-132-3p was significantly induced. The isolated BAC-derived exosomes suppressed expression of hepatic Srebf1, a predicted target of miR-132-3p. In an indirect co-culture system, BACs suppressed expression of hepatic Srebf1 and its target lipogenic genes; this effect was not seen with miR-132-3p-inhibited BACs. Srebf1 was experimentally validated as an miR-132-3p target. Cold stimuli consistently induced miR-132-3p expression in BAT and attenuated Srebf1 expression in the liver. Our results suggest that BAT-derived exosomal miR-132-3p acts as an endocrine factor that regulates hepatic lipogenesis for cold adaptation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Lignin is a cell wall component of vascular plants crucial for survival in terrestrial environments. While p-hydroxyphenyl lignin is minor, it is considered to be localised in the outermost part of the cell wall providing strong adhesion between cells, which determines cell shape. Transport of the lignin precursor from the cytosol to the cell wall is critical to regulate temporal and spatial lignin deposition; however, little information on the transport step is available. Here, we report transport activity of p-glucocoumaryl alcohol, a precursor of p-hydroxyphenyl lignin, in a broad-leaved tree (hybrid poplar, Populus sieboldii × P. grandidentata) and a coniferous tree (Japanese cypress, Chamaecyparis obtusa). Membrane vesicles of both trees were prepared from differentiating xylem with vigorous lignification and used for transport assays. Several inhibition assays indicated that not ABC transporters but the proton gradient and V-ATPase are involved in p-glucocoumaryl alcohol transport depending on ATP. These results support the hypothesis that p-glucocoumaryl alcohol is loaded into the secretory vesicles and delivered to the cell wall by exocytosis. Furthermore, this transport mechanism was common in both poplar and Japanese cypress, strongly suggesting that p-glucocoumaryl alcohol transport in the differentiating xylem is conserved within woody plants.

Ethanologenic white-rot fungus Phlebia sp. MG-60-P2 produces ethanol directly from several lignocelluloses. Efficient gene silencing methods are needed for metabolic engineering of this fungus for biorefinery use. In this study, we evaluated the effectiveness of RNAi-mediated silencing of the pyruvate decarboxylase gene of Phlebia sp. MG-60-P2 (MGpdc1). The RNAi lines generated showed a variety of suppression levels of ethanol production and MGpdc1 expression, and two selected strains led to different metabolic fluxes, resulting in rapid accumulation of xylitol from xylose. Knockdown lines KD2 and KD10 showed different strength of silencing. The moderate-inhibition line (KD10) showed faster xylitol accumulation from xylose than the severe-inhibition line (KD2). KD2, KD10 and knockout line KO77 showed higher extracellular peroxidase activity than the wild-type. Gene silencing using RNAi for MGpdc1 in the ethanologenic white-rot fungus Phlebia sp. MG-60-P2 is an effective first step in metabolic engineering to produce other chemicals besides ethanol. This high efficiency of transformation and silencing effect will make it possible to cotransform with multiple expression vectors which enhance the minor metabolic pathway or introduce exogenous metabolic reaction in Phlebia sp. MG-60-P2., (Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

The initiation of DNA replication is strictly regulated by multiple mechanisms to ensure precise duplication of chromosomes. In higher eukaryotes, activity of the Cdt1 protein is temporally regulated during the cell cycle, and deregulation of Cdt1 induces DNA re-replication. In previous studies, we showed that excess Cdt1 inhibits DNA replication by suppressing progression of replication forks in Xenopus egg extracts. Here, we investigated the functional regions of Cdt1 that are required for the inhibition of DNA replication. We constructed a series of N-terminally or C-terminally deleted mutants of Cdt1 and examined their inhibitory effects on DNA replication in Xenopus egg extracts. Our results showed that the region spanning amino acids (a. a.) 255-620 is required for efficient inhibition of DNA replication, and that, within this region, a. a. 255-289 have a critical role in inhibition. Moreover, one of the Cdt1 mutants, Cdt1 R285A, was compromised with respect to the licensing activity but still inhibited DNA replication. This result suggests that Cdt1 has an unforeseen function in the negative regulation of DNA replication, and that this function is located within a molecular region that is distinct from those required for the licensing activity., (Copyright © 2017 Elsevier Inc. All rights reserved.)