Publications by authors named "Hiroyuki Mori"

125 Publications

Cohort Profile: The Assessment from Preschool to Puberty-Longitudinal Epidemiological (APPLE) study in Hirosaki, Japan.

Int J Epidemiol 2021 Aug 19. Epub 2021 Aug 19.

Department of Psychiatry and Behavioral Sciences, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USADepartment of Neuropsychiatry, Graduate School of Medicine, Hirosaki University, Hirosaki, Aomori, JapanGraduate School of Health Sciences, Hirosaki University, Hirosaki, Aomori, JapanResearch Center for Child Mental Development, Graduate School of Medicine, Hirosaki University, Hirosaki, Aomori, Japan.

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http://dx.doi.org/10.1093/ije/dyab112DOI Listing
August 2021

Non-canonical proline-tyrosine interactions with multiple host proteins regulate Ebola virus infection.

EMBO J 2021 Sep 2;40(18):e105658. Epub 2021 Aug 2.

Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA.

The Ebola virus VP30 protein interacts with the viral nucleoprotein and with host protein RBBP6 via PPxPxY motifs that adopt non-canonical orientations, as compared to other proline-rich motifs. An affinity tag-purification mass spectrometry approach identified additional PPxPxY-containing host proteins hnRNP L, hnRNPUL1, and PEG10, as VP30 interactors. hnRNP L and PEG10, like RBBP6, inhibit viral RNA synthesis and EBOV infection, whereas hnRNPUL1 enhances. RBBP6 and hnRNP L modulate VP30 phosphorylation, increase viral transcription, and exert additive effects on viral RNA synthesis. PEG10 has more modest inhibitory effects on EBOV replication. hnRNPUL1 positively affects viral RNA synthesis but in a VP30-independent manner. Binding studies demonstrate variable capacity of the PPxPxY motifs from these proteins to bind VP30, define PxPPPPxY as an optimal binding motif, and identify the fifth proline and the tyrosine as most critical for interaction. Competition binding and hydrogen-deuterium exchange mass spectrometry studies demonstrate that each protein binds a similar interface on VP30. VP30 therefore presents a novel proline recognition domain that is targeted by multiple host proteins to modulate viral transcription.
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http://dx.doi.org/10.15252/embj.2020105658DOI Listing
September 2021

Adipocyte-Specific Deletion of Lamin A/C Largely Models Human Familial Partial Lipodystrophy Type 2.

Diabetes 2021 Sep 4;70(9):1970-1984. Epub 2021 Jun 4.

Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI

Mechanisms by which autosomal recessive mutations in cause familial partial lipodystrophy type 2 (FPLD2) are poorly understood. To investigate the function of lamin A/C in adipose tissue, we created mice with an adipocyte-specific loss of ( ). Although mice develop and maintain adipose tissues in early postnatal life, they show a striking and progressive loss of white and brown adipose tissues as they approach sexual maturity. mice exhibit surprisingly mild metabolic dysfunction on a chow diet, but on a high-fat diet they share many characteristics of FPLD2 including hyperglycemia, hepatic steatosis, hyperinsulinemia, and almost undetectable circulating adiponectin and leptin. Whereas mice have reduced regulated and constitutive bone marrow adipose tissue with a concomitant increase in cortical bone, FPLD2 patients have reduced bone mass and bone mineral density compared with controls. In cell culture models of deficiency, mesenchymal precursors undergo adipogenesis without impairment, whereas fully differentiated adipocytes have increased lipolytic responses to adrenergic stimuli. mice faithfully reproduce many characteristics of FPLD2 and thus provide a unique animal model to investigate mechanisms underlying -dependent loss of adipose tissues.
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http://dx.doi.org/10.2337/db20-1001DOI Listing
September 2021

The molecular and metabolic program by which white adipocytes adapt to cool physiologic temperatures.

PLoS Biol 2021 05 12;19(5):e3000988. Epub 2021 May 12.

Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America.

Although visceral adipocytes located within the body's central core are maintained at approximately 37°C, adipocytes within bone marrow, subcutaneous, and dermal depots are found primarily within the peripheral shell and generally exist at cooler temperatures. Responses of brown and beige/brite adipocytes to cold stress are well studied; however, comparatively little is known about mechanisms by which white adipocytes adapt to temperatures below 37°C. Here, we report that adaptation of cultured adipocytes to 31°C, the temperature at which distal marrow adipose tissues and subcutaneous adipose tissues often reside, increases anabolic and catabolic lipid metabolism, and elevates oxygen consumption. Cool adipocytes rely less on glucose and more on pyruvate, glutamine, and, especially, fatty acids as energy sources. Exposure of cultured adipocytes and gluteal white adipose tissue (WAT) to cool temperatures activates a shared program of gene expression. Cool temperatures induce stearoyl-CoA desaturase-1 (SCD1) expression and monounsaturated lipid levels in cultured adipocytes and distal bone marrow adipose tissues (BMATs), and SCD1 activity is required for acquisition of maximal oxygen consumption at 31°C.
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http://dx.doi.org/10.1371/journal.pbio.3000988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8143427PMC
May 2021

Inverse renormalization group based on image super-resolution using deep convolutional networks.

Sci Rep 2021 May 5;11(1):9617. Epub 2021 May 5.

Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan.

The inverse renormalization group is studied based on the image super-resolution using the deep convolutional neural networks. We consider the improved correlation configuration instead of spin configuration for the spin models, such as the two-dimensional Ising and three-state Potts models. We propose a block-cluster transformation as an alternative to the block-spin transformation in dealing with the improved estimators. In the framework of the dual Monte Carlo algorithm, the block-cluster transformation is regarded as a transformation in the graph degrees of freedom, whereas the block-spin transformation is that in the spin degrees of freedom. We demonstrate that the renormalized improved correlation configuration successfully reproduces the original configuration at all the temperatures by the super-resolution scheme. Using the rule of enlargement, we repeatedly make inverse renormalization procedure to generate larger correlation configurations. To connect thermodynamics, an approximate temperature rescaling is discussed. The enlarged systems generated using the super-resolution satisfy the finite-size scaling.
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http://dx.doi.org/10.1038/s41598-021-88605-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099887PMC
May 2021

Non-Contact Heart-Rate Measurement Method Using Both Transmitted Wave Extraction and Wavelet Transform.

Sensors (Basel) 2021 Apr 13;21(8). Epub 2021 Apr 13.

Denso Corporation, Kariya, Aichi 448-8661, Japan.

Continuous monitoring of heart-rate is expected to lead to early detection of physical discomfort. In this study, we propose a non-contact heart-rate measurement method which can be used in an environment such as driver heart-rate monitoring with body movement. The method is based on the electric field strength transmitted through the human body that changes with the diastole and systole of the heart. Unlike conventional displacement detection of the skin surface, we attempted to capture changes in the internal structure of the human body by irradiating the human body with microwaves and acquiring microwaves that pass through the heart. We first estimated the electric field strength transmitted through the heart using three receiving sensors to reduce the body movement effect. Then we decomposed the estimated transmitted electric field using stationary wavelet transform to eliminate significant distortion due to body movement. As a result, we achieved an estimation accuracy of heart-rate as high as 98% in a verification experiment with normal body movement.
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http://dx.doi.org/10.3390/s21082735DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069581PMC
April 2021

Suppression of optineurin impairs the progression of hepatocellular carcinoma through regulating mitophagy.

Cancer Med 2021 03 18;10(5):1501-1514. Epub 2021 Feb 18.

Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.

Autophagy removes damaged organelles to inhibit malignant transformation during tumor initiation. Once a cancer matures, it uses the autophagic pathway as an energy source. Optineurin (OPTN) is an autophagy adaptor protein that recruits microtubule-associated protein 1 light chain 3, an autophagosome marker, to the autophagosome. Despite studies of the relation between cancer progression and autophagy adaptor proteins, there are no reports to our knowledge of a correlation between hepatocellular carcinoma (HCC) and OPTN. We aimed here to investigate the effects of OPTN expression on HCC progression through autophagy. Immunohistochemistry was used to measure the OPTN expression in the tissues of 141 Japanese patients with HCC. The effects of OPTN expression on HCC progression and mitophagy were assessed using an OPTN knockout (KO) cell line in vitro. We used this KO cell line to establish and exploit a mouse model of HCC to determine the effects of OPTN expression on tumor progression. Immunohistochemical analysis showed that patients with elevated expression of OPTN experienced shorter overall survival (OS) and recurrence-free survival (RFS). OPTN KO cells proliferated relatively slower versus wild-type (WT) cells in vitro. Western blot analysis showed that mitophagy was suppressed in OPTN KO cells, and ATP synthesis and beta-oxidation were reduced. The mouse model of HCC showed that OPTN KO cells formed smaller tumors versus WT cells less 10 weeks after implantation. Overall, the present findings suggest that OPTN is a key mediator of mitophagy that contributes to HCC progression through mitochondrial energy production.
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http://dx.doi.org/10.1002/cam4.3519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7940236PMC
March 2021

Endoplasmic reticulum-associated degradation is required for nephrin maturation and kidney glomerular filtration function.

J Clin Invest 2021 04;131(7)

Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.

Podocytes are key to the glomerular filtration barrier by forming a slit diaphragm between interdigitating foot processes; however, the molecular details and functional importance of protein folding and degradation in the ER remain unknown. Here, we show that the SEL1L-HRD1 protein complex of ER-associated degradation (ERAD) is required for slit diaphragm formation and glomerular filtration function. SEL1L-HRD1 ERAD is highly expressed in podocytes of both mouse and human kidneys. Mice with podocyte-specific Sel1L deficiency develop podocytopathy and severe congenital nephrotic syndrome with an impaired slit diaphragm shortly after weaning and die prematurely, with a median lifespan of approximately 3 months. We show mechanistically that nephrin, a type 1 membrane protein causally linked to congenital nephrotic syndrome, is an endogenous ERAD substrate. ERAD deficiency attenuated the maturation of nascent nephrin, leading to its retention in the ER. We also show that various autosomal-recessive nephrin disease mutants were highly unstable and broken down by SEL1L-HRD1 ERAD, which attenuated the pathogenicity of the mutants toward the WT allele. This study uncovers a critical role of SEL1L-HRD1 ERAD in glomerular filtration barrier function and provides insights into the pathogenesis associated with autosomal-recessive disease mutants.
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http://dx.doi.org/10.1172/JCI143988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8011890PMC
April 2021

Fine interaction profiling of VemP and mechanisms responsible for its translocation-coupled arrest-cancelation.

Elife 2020 12 15;9. Epub 2020 Dec 15.

Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.

Bacterial cells utilize monitoring substrates, which undergo force-sensitive translation elongation arrest, to feedback-regulate a Sec-related gene. VemP controls the expression of SecD/F that stimulates a late step of translocation by undergoing export-regulated elongation arrest. Here, we attempted at delineating the pathway of the VemP nascent-chain interaction with Sec-related factors, and identified the signal recognition particle (SRP) and PpiD (a membrane-anchored periplasmic chaperone) in addition to other translocon components and a ribosomal protein as interacting partners. Our results showed that SRP is required for the membrane-targeting of VemP, whereas PpiD acts cooperatively with SecD/F in the translocation and arrest-cancelation of VemP. We also identified the conserved Arg-85 residue of VemP as a crucial element that confers PpiD-dependence to VemP and plays an essential role in the regulated arrest-cancelation. We propose a scheme of the arrest-cancelation processes of VemP, which likely monitors late steps in the protein translocation pathway.
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http://dx.doi.org/10.7554/eLife.62623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7793623PMC
December 2020

Utilization of the Maternal and Child Health Handbook in Early Identification of Autism Spectrum Disorder and Other Neurodevelopmental Disorders.

Autism Res 2021 03 29;14(3):551-559. Epub 2020 Nov 29.

Department of Neuropsychiatry, Graduate School of Medicine, Hirosaki University, Aomori, Japan.

There is relatively little information about prospectively reported developmental milestones from caregivers of children who go on to be diagnosed with neurodevelopmental disorders (NDDs), including autism spectrum disorder (ASD). The current study examined rates of early skill attainment in 5-year-old children who participated in a comprehensive in-person assessment for NDDs in Hirosaki in Japan. Developmental milestone data were extracted from their Maternal and Child Health Handbook (MCHH), a booklet distributed to all pregnant women as part of universal health care. Seven hundred and twenty children underwent the assessment, among whom 455 received one or more NDD diagnoses (ASD: n = 124, non-ASD NDD: n = 331). Developmental skills were organized into four domains (motor, social interaction, communication, self-help), and the cumulative number of potential delays in each domain was calculated for each participant within three different age ranges (by 12 months, by 24 months, and by 36 months). Even by age 12 months, children with ASD/NDDs showed more potential delays across domains compared to those who received no NDD diagnosis. However, differences between those with ASD and those with non-ASD NDDs were not apparent until 24 months for social interaction and communication, and 36 months for self-help. These findings provide insights into specific behaviors that could be used to screen for ASD and other NDDs. In addition, the present study indicates the potential utility of the MCHH as a broadband screening tool to educate parents about what to look for in charting their child's early development. LAY SUMMARY: The present study examined prospectively charted developmental milestones from home-based records used as part of universal health care in 720 5-year-old children from Hirosaki, Japan. All children participated in a comprehensive evaluation to determine if they met criteria for a neurodevelopmental disorder (NDD), including autism spectrum disorder (ASD). Compared to those who received no NDD diagnosis, children with NDDs exhibited higher rates of potential delays across developmental domains, including social interaction, communication, and self-help. For some children, these delays were apparent before the age of 12 months. Differences between diagnostic groups became even more pronounced by 24 and 36 months, well before the average age of diagnosis. This suggests that home-based records can be useful tools to educate caregivers about what to look for in charting their child's early development and could assist with early screening efforts.
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http://dx.doi.org/10.1002/aur.2442DOI Listing
March 2021

Amino Acids Enhance Polyubiquitination of Rheb and Its Binding to mTORC1 by Blocking Lysosomal ATXN3 Deubiquitinase Activity.

Mol Cell 2020 11;80(3):437-451.e6

Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA; Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1137 E. Catherine St., Ann Arbor, MI 48109-5622, USA; Department of Internal Medicine, University of Michigan Medical School, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5368, USA. Electronic address:

Amino-acid-induced lysosomal mechanistic target of rapamycin complex 1 (mTORC1) localization through the Rag GTPases is a critical step for its activation by Rheb GTPase. However, how the mTORC1 interacts with Rheb on the lysosome remains elusive. We report that amino acids enhance the polyubiquitination of Rheb (Ub-Rheb), which shows a strong binding preference for mTORC1 and supports its activation, while the Ub-Rheb is subjected to subsequent degradation. Mechanistically, we identified ATXN3 as a Ub-Rheb deubiquitinase whose lysosomal localization is blocked by active Rag heterodimer in response to amino acid stimulation. Consistently, cells lacking functional Rag heterodimer on the lysosome accumulate Ub-Rheb, and blockade of its degradation instigates robust lysosomal mTORC1 localization and its activation without the Ragulator-Rag system. Thus, polyubiquitination of Rheb is an important post-translational modification, which facilitates the binding of mTORC1 to Rheb on the lysosome and is another crosstalk between the amino acid and growth factor signaling for mTORC1 activation.
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http://dx.doi.org/10.1016/j.molcel.2020.10.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7665239PMC
November 2020

Reversible autoinhibitory regulation of metallopeptidase BepA for selective β-barrel protein degradation.

Proc Natl Acad Sci U S A 2020 11 22;117(45):27989-27996. Epub 2020 Oct 22.

Institute for Frontier Life and Medical Sciences, Kyoto University, 606-8507 Kyoto, Japan;

periplasmic zinc-metallopeptidase BepA normally functions by promoting maturation of LptD, a β-barrel outer-membrane protein involved in biogenesis of lipopolysaccharides, but degrades it when its membrane assembly is hampered. These processes should be properly regulated to ensure normal biogenesis of LptD. The underlying mechanism of regulation, however, remains to be elucidated. A recently solved BepA structure has revealed unique features: In particular, the active site is buried in the protease domain and conceivably inaccessible for substrate degradation. Additionally, the His-246 residue in the loop region containing helix α9 (α9/H246 loop), which has potential flexibility and covers the active site, coordinates the zinc ion as the fourth ligand to exclude a catalytic water molecule, thereby suggesting that the crystal structure of BepA represents a latent form. To examine the roles of the α9/H246 loop in the regulation of BepA activity, we constructed BepA mutants with a His-246 mutation or a deletion of the α9/H246 loop and analyzed their activities in vivo and in vitro. These mutants exhibited an elevated protease activity and, unlike the wild-type BepA, degraded LptD that is in the normal assembly pathway. In contrast, tethering of the α9/H246 loop repressed the LptD degradation, which suggests that the flexibility of this loop is important to the exhibition of protease activity. Based on these results, we propose that the α9/H246 loop undergoes a reversible structural change that enables His-246-mediated switching (histidine switch) of its protease activity, which is important for regulated degradation of stalled/misassembled LptD.
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http://dx.doi.org/10.1073/pnas.2010301117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668163PMC
November 2020

Distributional patterns of item responses and total scores of the Patient Health Questionnaire for Adolescents in a general population sample of adolescents in Japan.

Psychiatry Clin Neurosci 2020 Nov 29;74(11):628-629. Epub 2020 Sep 29.

Research Center for Child Mental Development, Graduate School of Medicine, Hirosaki University, Hirosaki, Japan.

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http://dx.doi.org/10.1111/pcn.13148DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7702070PMC
November 2020

Wnt/β-catenin signaling regulates adipose tissue lipogenesis and adipocyte-specific loss is rigorously defended by neighboring stromal-vascular cells.

Mol Metab 2020 12 9;42:101078. Epub 2020 Sep 9.

Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA; Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA. Electronic address:

Objective: Canonical Wnt/β-catenin signaling is a well-studied endogenous regulator of mesenchymal cell fate determination, promoting osteoblastogenesis and inhibiting adipogenesis. However, emerging genetic evidence in humans links a number of Wnt pathway members to body fat distribution, obesity, and metabolic dysfunction, suggesting that this pathway also functions in adipocytes. Recent studies in mice have uncovered compelling evidence that the Wnt signaling pathway plays important roles in adipocyte metabolism, particularly under obesogenic conditions. However, complexities in Wnt signaling and differences in experimental models and approaches have thus far limited our understanding of its specific roles in this context.

Methods: To investigate roles of the canonical Wnt pathway in the regulation of adipocyte metabolism, we generated adipocyte-specific β-catenin (β-cat) knockout mouse and cultured cell models. We used RNA sequencing, ChIP sequencing, and molecular approaches to assess expression of Wnt targets and lipogenic genes. We then used functional assays to evaluate effects of β-catenin deficiency on adipocyte metabolism, including lipid and carbohydrate handling. In mice maintained on normal chow and high-fat diets, we assessed the cellular and functional consequences of adipocyte-specific β-catenin deletion on adipose tissues and systemic metabolism.

Results: We report that in adipocytes, the canonical Wnt/β-catenin pathway regulates de novo lipogenesis (DNL) and fatty acid monounsaturation. Further, β-catenin mediates effects of Wnt signaling on lipid metabolism in part by transcriptional regulation of Mlxipl and Srebf1. Intriguingly, adipocyte-specific loss of β-catenin is sensed and defended by CD45/CD31 stromal cells to maintain tissue-wide Wnt signaling homeostasis in chow-fed mice. With long-term high-fat diet, this compensatory mechanism is overridden, revealing that β-catenin deletion promotes resistance to diet-induced obesity and adipocyte hypertrophy and subsequent protection from metabolic dysfunction.

Conclusions: Taken together, our studies demonstrate that Wnt signaling in adipocytes is required for lipogenic gene expression, de novo lipogenesis, and lipid desaturation. In addition, adipose tissues rigorously defend Wnt signaling homeostasis under standard nutritional conditions, such that stromal-vascular cells sense and compensate for adipocyte-specific loss. These findings underscore the critical importance of this pathway in adipocyte lipid metabolism and adipose tissue function.
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http://dx.doi.org/10.1016/j.molmet.2020.101078DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7554252PMC
December 2020

Wntless regulates lipogenic gene expression in adipocytes and protects against diet-induced metabolic dysfunction.

Mol Metab 2020 09 20;39:100992. Epub 2020 Apr 20.

Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA; Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA. Electronic address:

Objective: Obesity is a key risk factor for many secondary chronic illnesses, including type 2 diabetes and cardiovascular disease. Canonical Wnt/β-catenin signaling is established as an important endogenous inhibitor of adipogenesis. This pathway is operative in mature adipocytes; however, its roles in this context remain unclear due to complexities of Wnt signaling and differences in experimental models. In this study, we used novel cultured cell and mouse models to investigate functional roles of Wnts secreted from adipocytes.

Methods: We generated adipocyte-specific Wntless (Wls) knockout mice and cultured cell models to investigate molecular and metabolic consequences of disrupting Wnt secretion from mature adipocytes. To characterize Wls-deficient cultured adipocytes, we evaluated the expression of Wnt target and lipogenic genes and the downstream functional effects on carbohydrate and lipid metabolism. We also investigated the impact of adipocyte-specific Wls deletion on adipose tissues and global glucose metabolism in mice fed normal chow or high-fat diets.

Results: Many aspects of the Wnt signaling apparatus are expressed and operative in mature adipocytes, including the Wnt chaperone Wntless. Deletion of Wntless in cultured adipocytes results in the inhibition of de novo lipogenesis and lipid monounsaturation, likely through repression of Srebf1 (SREBP1c) and Mlxipl (ChREBP) and impaired cleavage of immature SREBP1c into its active form. Adipocyte-specific Wls knockout mice (Wls) have lipogenic gene expression in adipose tissues and isolated adipocytes similar to that of controls when fed a normal chow diet. However, closer investigation reveals that a subset of Wnts and downstream signaling targets are upregulated within stromal-vascular cells of Wls mice, suggesting that adipose tissues defend loss of Wnt secretion from adipocytes. Interestingly, this compensation is lost with long-term high-fat diet challenges. Thus, after six months of a high-fat diet, Wls mice are characterized by decreased adipocyte lipogenic gene expression, reduced visceral adiposity, and improved glucose homeostasis.

Conclusions: Taken together, these studies demonstrate that adipocyte-derived Wnts regulate de novo lipogenesis and lipid desaturation and coordinate the expression of lipogenic genes in adipose tissues. In addition, we report that Wnt signaling within adipose tissues is defended, such that a loss of Wnt secretion from adipocytes is sensed and compensated for by neighboring stromal-vascular cells. With chronic overnutrition, this compensatory mechanism is lost, revealing that Wls mice are resistant to diet-induced obesity, adipocyte hypertrophy, and metabolic dysfunction.
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http://dx.doi.org/10.1016/j.molmet.2020.100992DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7264081PMC
September 2020

Machine-Learning Studies on Spin Models.

Sci Rep 2020 02 7;10(1):2177. Epub 2020 Feb 7.

Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, 138671, Singapore, Singapore.

With the recent developments in machine learning, Carrasquilla and Melko have proposed a paradigm that is complementary to the conventional approach for the study of spin models. As an alternative to investigating the thermal average of macroscopic physical quantities, they have used the spin configurations for the classification of the disordered and ordered phases of a phase transition through machine learning. We extend and generalize this method. We focus on the configuration of the long-range correlation function instead of the spin configuration itself, which enables us to provide the same treatment to multi-component systems and the systems with a vector order parameter. We analyze the Berezinskii-Kosterlitz-Thouless (BKT) transition with the same technique to classify three phases: the disordered, the BKT, and the ordered phases. We also present the classification of a model using the training data of a different model.
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http://dx.doi.org/10.1038/s41598-020-58263-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7005704PMC
February 2020

Rimonabant suppresses RNA transcription of hepatitis B virus by inhibiting hepatocyte nuclear factor 4α.

Microbiol Immunol 2020 May 25;64(5):345-355. Epub 2020 Feb 25.

Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.

Chronic infection with hepatitis B virus (HBV) sometime induces lethal cirrhosis and hepatocellular carcinoma. Although nucleot(s)ide analogs are used as main treatment for HBV infection, the emergence of the drug-resistant viruses has become a problem. To discover novel antivirals with low side effects and low risk of emergence of resistant viruses, screening for anti-HBV compounds was performed with compound libraries of inhibitors targeting G-protein-coupled receptors (GPCRs). HepG2-hNTCP C4 cells infected with HBV were treated with various GPCR inhibitors and harvested at 14 day postinfection for quantification of core protein in the first screening or relaxed circular DNA in the second screening. Finally, we identified a cannabinoid receptor 1 inhibitor, rimonabant, as a candidate showing anti-HBV effect. In HepG2-hNTCP C4 cells, treatment with rimonabant suppressed HBV propagation at the viral RNA transcription step but had no effect on entry or covalently closed circular DNA level. The values of half maximal inhibitory concentration, half maximal effective concentration, and selectivity index of rimonabant in primary human hepatocyte (PHH) are 2.77 μm, 40.4 μm, and 14.6, respectively. Transcriptome analysis of rimonabant-treated primary hepatocytes by RNA sequencing revealed that the transcriptional activity of hepatocyte nuclear factor 4α (HNF4α), which is known to stimulate viral RNA synthesis, was depressed. By treatment of PHH with rimonabant, the expression level of HNF4α protein and the production of the messenger RNAs (mRNAs) of downstream factors promoted by HNF4α were reduced while the amount of HNF4α mRNA was not altered. These results suggest that treatment with rimonabant suppresses HBV propagation through the inhibition of HNF4α activity.
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http://dx.doi.org/10.1111/1348-0421.12777DOI Listing
May 2020

Tree of motility - A proposed history of motility systems in the tree of life.

Genes Cells 2020 Jan;25(1):6-21

Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Kanagawa, Japan.

Motility often plays a decisive role in the survival of species. Five systems of motility have been studied in depth: those propelled by bacterial flagella, eukaryotic actin polymerization and the eukaryotic motor proteins myosin, kinesin and dynein. However, many organisms exhibit surprisingly diverse motilities, and advances in genomics, molecular biology and imaging have showed that those motilities have inherently independent mechanisms. This makes defining the breadth of motility nontrivial, because novel motilities may be driven by unknown mechanisms. Here, we classify the known motilities based on the unique classes of movement-producing protein architectures. Based on this criterion, the current total of independent motility systems stands at 18 types. In this perspective, we discuss these modes of motility relative to the latest phylogenetic Tree of Life and propose a history of motility. During the ~4 billion years since the emergence of life, motility arose in Bacteria with flagella and pili, and in Archaea with archaella. Newer modes of motility became possible in Eukarya with changes to the cell envelope. Presence or absence of a peptidoglycan layer, the acquisition of robust membrane dynamics, the enlargement of cells and environmental opportunities likely provided the context for the (co)evolution of novel types of motility.
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http://dx.doi.org/10.1111/gtc.12737DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7004002PMC
January 2020

An earbud-type wearable (A hearable) with vital parameter sensors for early detection and prevention of heat-stroke.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:7049-7055

Heat-stroke has become a serious problem in Japan, especially for elderly citizens. For the early detection and prevention of heat-stroke, a wearable health monitor for in-ear use is developed which is subsequently called "Hearable". It aims to measure three vital parameters: Core body temperature, sweat rate and sweat or interstitial sodium ion (Na) concentration. The eardrum is a good place to measure the core body temperature, because it is close to the carotid artery and the brain. We develop a hearable prototype and it consists of an audio earbud, a sensor earbud and a micro controller. Concerning the sensor earbud, a present prototype includes an eardrum (tympanic) temperature sensor and a sweat rate sensor and we implement two variants. Variant-1 focuses on the sweat rate sensing using a humidity & temperature sensor located close to the eardrum and Variant-2 focuses on the eardrum temperature sensing using an IR temperature sensor. Concerning the sweat rate sensing, unlike conventional sweat sensors, our prototypes do not include an air flow pump, which is typically used to determine the air flow rate. We demonstrate the accuracy of sweat rate sensing based on the air flow rate measured from the evaporation of defined amount of water. We use Variant-2 to demonstrate the monitoring of the eardrum temperature and the sweat rate to differentiate a calm state and jogging.
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http://dx.doi.org/10.1109/EMBC.2019.8856821DOI Listing
July 2019

Effect of line tension on axisymmetric nanoscale capillary bridges at the liquid-vapor equilibrium.

Phys Rev E 2019 Oct;100(4-1):042802

Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.

The effect of line tension on the axisymmetric nanoscale capillary bridge between two identical substrates with convex, concave, and flat geometry at the liquid-vapor equilibrium is theoretically studied. The modified Young's equation for the contact angle, which takes into account the effect of line tension, is derived on a general axisymmetric curved surface using the variational method. Even without the effect of line tension, the parameter space where the bridge can exist is limited simply by the geometry of substrates. The modified Young's equation further restricts the space where the bridge can exist when the line tension is positive because the equilibrium contact angle always remains finite and the wetting state near the zero contact angle cannot be realized. It is shown that the interplay of the geometry and the positive line tension restricts the formation of capillary bridge.
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http://dx.doi.org/10.1103/PhysRevE.100.042802DOI Listing
October 2019

Regulation of adipocyte differentiation and metabolism by lansoprazole.

Life Sci 2019 Dec 20;239:116897. Epub 2019 Oct 20.

Research Center of Transport Protein for Medical Innovation, Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand; Excellent Center for Drug Discovery (ECDD), Faculty of Science, Mahidol University, Bangkok, Thailand. Electronic address:

Aims: Lansoprazole (LPZ) is one of the most commonly prescribed drugs for treatment of acid-related diseases, and it is increasingly recognized for its potential application as an anti-diabetic therapy. Although LPZ target tissues remain poorly understood, possible sites of action include adipose tissue. In this study, we assessed effects of LPZ on adipocyte differentiation and function by using 3T3-L1 preadipocytes and HFD-induced obesity mice as an in vitro and in vivo model, respectively.

Main Methods: Oil red O staining and intracellular triacylglycerol content were used to determine lipid accumulation. Glucose uptake was performed to measure mature adipocyte function. Expression of adipocyte genes was determined by qRT-PCR and immunoblotting.

Key Findings: LPZ has dual effects on differentiation of 3T3-L1 cells. At low concentrations, LPZ enhanced adipocyte differentiation via induction of PPARγ and C/EBPα, two master adipogenic transcription factors, as well as lipogenic proteins, ACC1 and FASN. Increasing of adipocyte number subsequently increased basal and insulin-stimulated glucose uptake, and expression of Glut4 mRNA. Conversely, high concentrations of LPZ strongly inhibited differentiation and expression of PPARγ and C/EBPα, and maintained expression of preadipocytes markers, β-catenin and Pref-1. Inhibition of adipogenesis by LPZ reduced mature adipocyte number, Glut4 mRNA expression and insulin-stimulated glucose uptake. In addition, treatment with LPZ at 200 mg/kg significantly reduced body weight gain and total fat mass in HFD-induced obese mice.

Significance: These results indicate that effects of LPZ on adipocyte differentiation are dependent on concentration and are correlated with PPARγ and C/EBPα.
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http://dx.doi.org/10.1016/j.lfs.2019.116897DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7058925PMC
December 2019

Dynamics of Reporter Viruses.

J Virol 2019 11 29;93(22). Epub 2019 Oct 29.

Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan

Recombinant viruses possessing reporter proteins have been generated for virus research. In the case of the family , we recently generated recombinant viruses, including the hepatitis C virus of the genus , Japanese encephalitis virus (JEV) of the genus , and bovine viral diarrhea virus of the genus ; all three viruses possess an 11-amino-acid subunit derived from NanoLuc luciferase (HiBiT). Here, we further developed the recombinant viruses and investigated their utility Recombinant viruses harboring HiBiT in the E, NS1, or NS3 protein constructed based on the predicted secondary structure, solvent-accessible surface area, and root mean square fluctuation of the proteins exhibited comparable replication to that of the wild-type virus The recombinant JEV carrying HiBiT in the NS1 protein exhibited propagation in mice comparable to that of the parental virus, and propagation of the recombinant was monitored by the luciferase activity. In addition, the recombinants of classical swine fever virus (CSFV) possessing HiBiT in the E or E2 protein also showed propagation comparable to that of the wild-type virus. The recombinant CSFV carrying HiBiT in E exhibited similar replication to the parental CSFV in pigs, and detection of viral propagation of this recombinant by luciferase activity was higher than that by quantitative PCR (qPCR). Taken together, these results demonstrated that the reporter viruses generated herein are powerful tools for elucidating the viral life cycle and pathogeneses and provide a robust platform for the development of novel antivirals. applications of reporter viruses are necessary to understand viral pathogenesis and provide a robust platform for antiviral development. In developing such applications, determination of an ideal locus to accommodate foreign genes is important, because insertion of foreign genes into irrelevant loci can disrupt the protein functions required for viral replication. Here, we investigated the criteria to determine ideal insertion sites of foreign genes from the protein structure of viral proteins. The recombinant viruses generated by our criteria exhibited propagation comparable to that of parental viruses Our proteomic approach based on the flexibility profile of viral proteins may provide a useful tool for constructing reporter viruses, including viruses.
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http://dx.doi.org/10.1128/JVI.01191-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6819943PMC
November 2019

G-CSF partially mediates effects of sleeve gastrectomy on the bone marrow niche.

J Clin Invest 2019 05 6;129(6):2404-2416. Epub 2019 May 6.

Department of Molecular & Integrative Physiology.

Bariatric surgeries are integral to the management of obesity and its metabolic complications. However, these surgeries cause bone loss and increase fracture risk through poorly understood mechanisms. In a mouse model, vertical sleeve gastrectomy (VSG) caused trabecular and cortical bone loss that was independent of sex, body weight, and diet, and this loss was characterized by impaired osteoid mineralization and bone formation. VSG had a profound effect on the bone marrow niche, with rapid loss of marrow adipose tissue, and expansion of myeloid cellularity, leading to increased circulating neutrophils. Following VSG, circulating granulocyte-colony stimulating factor (G-CSF) was increased in mice, and was transiently elevated in a longitudinal study of humans. Elevation of G-CSF was found to recapitulate many effects of VSG on bone and the marrow niche. In addition to stimulatory effects of G-CSF on myelopoiesis, endogenous G-CSF suppressed development of marrow adipocytes and hindered accrual of peak cortical and trabecular bone. Effects of VSG on induction of neutrophils and depletion of marrow adiposity were reduced in mice deficient for G-CSF; however, bone mass was not influenced. Although not a primary mechanism for bone loss with VSG, G-CSF plays an intermediary role for effects of VSG on the bone marrow niche.
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http://dx.doi.org/10.1172/JCI126173DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6546463PMC
May 2019

A photo-cross-linking approach to monitor protein dynamics in living cells.

Biochim Biophys Acta Gen Subj 2020 02 6;1864(2):129317. Epub 2019 Mar 6.

Institute for Frontier Life and Medical Sciences, Kyoto University, Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address:

Background: Proteins, which comprise one of the major classes of biomolecules that constitute a cell, interact with other cellular factors during both their biogenesis and functional states. Studying not only static but also transient interactions of proteins is important to understand their physiological roles and regulation mechanisms. However, only a limited number of methods are available to analyze the dynamic behaviors of proteins at the molecular level in a living cell. The site-directed in vivo photo-cross-linking approach is an elegant technique to capture protein interactions with high spatial resolution in a living cell.

Scope Of Review: Here, we review the in vivo photo-cross-linking approach including its recent applications and the potential problems to be considered. We also introduce a new in vivo photo-cross-linking-based technique (PiXie) to study protein dynamics with high spatiotemporal resolution.

Major Conclusions: In vivo photo-cross-linking enables us to capture weak/transient protein interactions with high spatial resolution, and allows for identification of interacting factors. Moreover, the PiXie approach can be used to monitor rapid folding/assembly processes of proteins in living cells.

General Significance: In vivo photo-cross-linking is a simple method that has been used to analyze the dynamic interactions of many cellular proteins. Originally developed in Escherichia coli, this system has been extended to studies in various organisms, making it a fundamental technique for investigating dynamic protein interactions in many cellular processes. This article is part of a Special issue entitled "Novel major techniques for visualizing 'live' protein molecules" edited by Dr. Daisuke Kohda.
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http://dx.doi.org/10.1016/j.bbagen.2019.03.003DOI Listing
February 2020

Heat shock transcription factor σ defective in membrane transport can be suppressed by transposon insertion into genes encoding a restriction enzyme subunit or a putative autotransporter in Escherichia coli.

Genes Genet Syst 2019 Jan 8;93(6):229-235. Epub 2018 Dec 8.

Institute for Frontier Life and Medical Sciences, Kyoto University.

Heat shock transcription factor σ of Escherichia coli plays a major role in protein homeostasis and requires membrane localization for regulation. We here report that a strongly deregulated I54N-σ mutant defective in association with the membrane can be phenotypically suppressed by Tn5 insertion into the mcrC or ydbA2 gene, encoding a restriction enzyme subunit or part of a putative autotransporter, respectively. The suppression is specific for mutant I54N-σ and reduces its activity but not its abundance or stability. Moreover, the deregulated phenotype of I54N-σ is effectively suppressed by a plasmid carrying the same mcrC::Tn5 mutation. In contrast, deletion of the mcrC or ydbA2 gene hardly affects I54N-σ activity. These results, taken together, suggest that the truncated form of McrC (and presumably also of YdbA2) protein produced by the Tn5 insertion interacts specifically with I54N-σ to reduce its activity without substantially affecting its amount or stability.
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http://dx.doi.org/10.1266/ggs.18-00040DOI Listing
January 2019

Induction of selective autophagy in cells replicating hepatitis C virus genome.

J Gen Virol 2018 12 12;99(12):1643-1657. Epub 2018 Oct 12.

1​Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita-shi, Osaka 565-0871, Japan.

Hepatitis C virus (HCV) infection is known to induce autophagy, but the mechanism of autophagy induced by HCV remains controversial. Here, we investigated the characteristics of autophagy induced by HCV infection. First, to examine the involvement of autophagy-related gene (ATG) proteins in HCV-induced LC3 lipidation, we established ATG5, ATG13 or ATG14 knockout (KO) Huh7.5.1 cell lines and confirmed that the accumulation of lipidated LC3 was induced in an ATG13- and ATG14-independent manner. On the other hand, HCV infectivity was not influenced by deficiencies in these genes. We also confirmed that LC3-positive dots were co-localized with ubiquitinated aggregates, and deficiency of ATG5 or ATG14 enhanced the accumulation of ubiquitinated aggregates compared to that in the restored cells, suggesting that HCV infection induces ATG5- and ATG14-dependent selective autophagy. Moreover, LC3-positive ubiquitinated aggregates accumulated near the site of the replication complex. We further examined autophagy flux in cells replicating HCV RNA using bafilomycin or E64d, and found that the increase of LC3 lipidation by treatment with bafilomycin or E64d was impaired in HCV-replicating cells, suggesting that autophagy flux is inhibited by the progress of HCV infection. Our present study suggests that (1) HCV RNA replication induces selective autophagy and (2) the progress of HCV infection impairs autophagy flux.
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http://dx.doi.org/10.1099/jgv.0.001161DOI Listing
December 2018

Monitoring substrate enables real-time regulation of a protein localization pathway.

FEMS Microbiol Lett 2018 06;365(11)

Faculty of Life Sciences and Institute for Protein Dynamics, Kyoto Sangyo University, Kita-Ku, Kyoto 603-8555, Japan.

Protein localization machinery supports cell survival and physiology, suggesting the potential importance of its expression regulation. Here, we summarize a remarkable scheme of regulation, which allows real-time feedback regulation of the machinery expression. A class of regulatory nascent polypeptides, called monitoring substrates, undergoes force-sensitive translation arrest. The resulting ribosome stalling on the mRNA then affects mRNA folding to expose the ribosome-binding site of the downstream target gene and upregulate its translation. The target gene encodes a component of the localization machinery, whose physical action against the monitoring substrate leads to arrest cancellation. Thus, this scheme of feedback loop allows the cell to adjust the amount of the machinery to correlate inversely with the effectiveness of the process at a given moment. The system appears to have emerged late in evolution, in which a narrow range of organisms selected a distinct monitoring substrate-machinery combination. Currently, regulatory systems of SecM-SecA, VemP-SecDF2 and MifM-YidC2 are known to occur in different bacterial species.
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http://dx.doi.org/10.1093/femsle/fny109DOI Listing
June 2018

Late diagnosis: a case of rapidly progressive extranodal NK/T cell lymphoma, nasal type.

BMJ Case Rep 2018 Feb 17;2018. Epub 2018 Feb 17.

General Internal Medicine, Kakogawa Chuo Shimin Hospital, Kakogawa, Hyogo, Japan.

Extranodal natural killer (NK)/T cell lymphoma, nasal type is a condition that has poor prognosis. Accurate diagnosis of lymphoma is made by pathological findings. We report a case of extranodal NK/T cell lymphoma, nasal type affecting the lung and liver and which was difficult to diagnose because of negative biopsy results from multiple sites. A 39-year-old man who had dry cough and fever for 1 month was referred to our hospital. He had pancytopenia and elevated serum levels of lactate dehydrogenase and soluble interleukin-2 receptor. Hepatosplenomegaly and multiple lung nodules were found on imaging study. Specimens of bronchoscopic lung, percutaneous liver, bone marrow and random skin biopsies were all negative. Open lung biopsy was not definitive. Unfortunately, disease progression was rapid and fatal before results of pleural fluid cytology and a second liver biopsy showed extranodal NK/T cell lymphoma, nasal type. This report focused on diagnostic planning for rapidly progressive extranodal NK/T-cell lymphoma, nasal type.
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http://dx.doi.org/10.1136/bcr-2017-221019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5836627PMC
February 2018

Bone marrow adipocytes resist lipolysis and remodeling in response to β-adrenergic stimulation.

Bone 2019 01 31;118:32-41. Epub 2018 Jan 31.

Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48105, USA; Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA. Electronic address:

Bone marrow adipose tissue (BMAT) is preserved or increased in states of caloric restriction. Similarly, we found that BMAT in the tail vertebrae, but not the red marrow in the tibia, resists loss of neutral lipid with acute, 48-hour fasting in rats. The mechanisms underlying this phenomenon and its seemingly distinct regulation from peripheral white adipose tissue (WAT) remain unknown. To test the role of β-adrenergic stimulation, a major regulator of adipose tissue lipolysis, we examined the responses of BMAT to β-adrenergic agonists. Relative to inguinal WAT, BMAT had reduced phosphorylation of hormone sensitive lipase (HSL) after treatment with pan-β-adrenergic agonist isoproterenol. Phosphorylation of HSL in response to β3-adrenergic agonist CL316,243 was decreased by an additional ~90% (distal tibia BMAT) or could not be detected (tail vertebrae). Ex vivo, adrenergic stimulation of lipolysis in purified BMAT adipocytes was also substantially less than iWAT adipocytes and had site-specific properties. Specifically, regulated bone marrow adipocytes (rBMAs) from proximal tibia and femur underwent lipolysis in response to both CL316,243 and forskolin, while constitutive BMAs from the tail responded only to forskolin. This occurred independently of changes in gene expression of β-adrenergic receptors, which were similar between adipocytes from iWAT and BMAT, and could not be explained by defective coupling of β-adrenergic receptors to lipolytic machinery through caveolin 1. Specifically, we found that whereas caveolin 1 was necessary to mediate maximal stimulation of lipolysis in iWAT, overexpression of caveolin 1 was insufficient to rescue impaired BMAT signaling. Lastly, we tested the ability of BMAT to respond to 72-hour treatment with CL316,243 in vivo. This was sufficient to cause beiging of iWAT adipocytes and a decrease in iWAT adipocyte cell size. By contrast, adipocyte size in the tail BMAT and distal tibia remained unchanged. However, within the distal femur, we identified a subpopulation of BMAT adipocytes that underwent lipid droplet remodeling. This response was more pronounced in females than in males and resembled lipolysis-induced lipid partitioning rather than traditional beiging. In summary, BMAT has the capacity to respond to β-adrenergic stimuli, however, its responses are muted and BMAT generally resists lipid hydrolysis and remodeling relative to iWAT. This resistance is more pronounced in distal regions of the skeleton where the BMAT adipocytes are larger with little intervening hematopoiesis, suggesting that there may be a role for both cell-autonomous and microenvironmental determinants. Resistance to β-adrenergic stimuli further separates BMAT from known regulators of energy partitioning and contributes to our understanding of why BMAT is preserved in states of fasting and caloric restriction.
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http://dx.doi.org/10.1016/j.bone.2018.01.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6062480PMC
January 2019

Identification and characterization of a translation arrest motif in VemP by systematic mutational analysis.

J Biol Chem 2018 02 9;293(8):2915-2926. Epub 2018 Jan 9.

Institute for Frontier Life and Medical Sciences, Kyoto University, Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.

VemP ( protein xport onitoring olypeptide) is a secretory protein comprising 159 amino acid residues, which functions as a secretion monitor in and regulates expression of the downstream genes. When VemP export is compromised, its translation specifically undergoes elongation arrest at the position where the Gln codon of encounters the P-site in the translating ribosome, resulting in up-regulation of V.SecDF2 production. Although our previous study suggests that many residues in a highly conserved C-terminal 20-residue region of VemP contribute to its elongation arrest, the exact role of each residue remains unclear. Here, we constructed a reporter system to easily and exactly monitor the arrest efficiency of VemP. Using this reporter system, we systematically performed a mutational analysis of the 20 residues (His-Phe) to identify and characterize the arrest motif. Our results show that 15 residues in the conserved region participate in elongation arrest and that multiple interactions between important residues in VemP and in the interior of the exit tunnel contribute to the elongation arrest of VemP. The arrangement of these important residues induced by specific secondary structures in the ribosomal tunnel is critical for the arrest. Pro scanning analysis of the preceding segment (Met-Phe) revealed a minor role of this region in the arrest. Considering these results, we conclude that the arrest motif in VemP is mainly composed of the highly conserved multiple residues in the C-terminal region.
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http://dx.doi.org/10.1074/jbc.M117.816561DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5827439PMC
February 2018
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