bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating the Role of Trehalose Metabolism in Resistance to Abiotic Stress in the Filamentous Fungus Fusarium verticillioides
Authors: Oberlie Nicole Ruth , McMillan Sarah D. , Brown Daren W. , McQuade Kristi L. 
Published: June 2021

Fusarium verticillioides is a maize pathogen that synthesizes toxic secondary metabolites called fumonisins, which can contaminate grain and cause disease in livestock and humans. We showed previously that an F. verticillioides strain (Δtps1) that lacks the gene coding for trehalose‐6‐phosphate (T6P) synthase produces no trehalose, has reduced pathogenicity, and produces significantly less fumonisins than wild type. Here, we characterize the effects of various abiotic stresses on spore viability and growth rates of the wild‐type and Δtps1 strains as well as strains expressing a catalytically inactive form of T6P synthase, which are also trehalose deficient. We show using a colony count assay that desiccation decreases the viability of spores from trehalose‐deficient strains significantly more than spores from the wild‐type strain. Likewise, oxidative stress‐inducing compounds reduce both the growth rate and maximum culture density of trehalose‐deficient strains more than the wild‐type strain. Live/dead fluorescence staining indicates that oxidative stress decreases the viability of trehalose‐deficient strains more significantly than wild type. Together, these data suggest that trehalose is critical for tolerance to desiccation and oxidative stress in F. verticillioides.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
ESE‐1 Represses Formation of Tumor in vivo and Growth, Invasion and Migration of Human NSCLC Cells in vitro
Authors: Lou Zhiyuan , Lee Bok‐Soon , Ha Taekyu , Xu Yanrui , Kim Haeng‐Jun , Kim Chul‐Ho , Lee Seong‐Ho 
Published: June 2021

Lung cancer is the leading cause of cancer mortality in the United State due to poor prognosis. Identification of effective molecular target is essential for lung cancer prevention and therapy. Epithelial Specific ETS‐1 (ESE‐1) is a transcription factor that belongs to ETS superfamily and associated with development of several types of cancer. However, the significance of ESE‐1 in lung cancer remains unanswered. The objective of current study was to investigate if ESE‐1 expression influences tumorigenic and metastatic activity of human non‐small cell lung cancer (NSCLC). Overexpression of ESE‐1 repressed the anchorage‐independent growth of human NSCLC cells and led to an increase of G1 arrest and apoptosis. ESE‐1 expression repressed invasion and migration of human NSCLC cells. Xenograft study indicated that ESE‐1 expression inhibited formation and development of tumor. ESE‐1 is a downstream target of TGF‐β‐stimulated epithelial mesenchymal transition (EMT). Our findings indicate that ESE‐1 serves as a tumor repressor in human NSCLC.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Dysregulation of the Tumor Suppressor Tip60 and ATM Signaling Paradigm by the HIV Transactivator of Transcription
Authors: Simenauer Ari , Cota‐Gomez Adela 
Published: June 2021

Despite the longevity afforded by modern anti‐retroviral therapy, long‐term HIV infection increases the risk for pulmonary co‐morbidities associated with cell cycle dysregulation including lung cancer and pulmonary arterial hypertension. As such, we postulate that select viral factors, in particular the HIV transactivator of transcription (Tat), interfere with cellular processes involving tumor suppressors and other cell cycle regulators during chronic infection. Tat is well known to inhibit the activity of the tumor suppressor Tat Interacting Protein 60 kDa (Tip60), an acetyltransferase critical in the progression to cell cycle arrest and/or apoptosis. In response to stressors such as DNA damage and oxidative stress, Tip60 activates the cell cycle master regulator kinase Ataxia Telangiectasia Mutated (ATM) via acetylation, initiating a signaling cascade that culminates in the activation of a DNA damage response resulting in both short and long term cellular arrest. Thus, we hypothesize that inhibition of Tip60 by Tat interferes with cellular arrest in responses to these stressors and results in abnormal proliferation. We addressed the hypothesis using HeLa cells stably transfected to express Tat (HeLa‐TatIII). Utilizing an ATP based luminescent cell viability assay, we observed accelerated cell proliferation in HeLa‐TatIII compared to its HeLa wild‐type counterpart. Furthermore, immunoprecipitation experiments in HeLa‐WT cells confirmed a physical interaction between Tat and Tip60. Acetylation by Tip60 results in autophosphorylation of ATM at ser1981, and this phosphorylation event is a canonical marker for ATM activation. As such, we determined the phosphorylation state of ATM ser1981 after treatment with doxorubicin in HeLa‐WT and HeLa‐TatIII cells. We found that, following treatment with doxorubicin, ATM phosphorylation at ser1981 was severely attenuated in HeLa‐TatIII cells compared to HeLa‐WTs, suggesting a role for Tat in the inhibition of ATM activation. Taken together, these data support the role of the HIV Tat protein in dysregulation of cell cycle arrest via ATM signaling pathways. Whether HIV promotes cellular proliferation in co‐morbidities such as lung cancer and pulmonary arterial hypertension via these pathways remains to be addressed.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Polyunsaturated Fatty Acid Desaturase‐Mediated NAD+ Recycling Permits Ongoing Glycolysis and Cell Proliferation
Authors: Kim Wondong , Deik Amy , Florez Jose C. , Jacobs Suzanne B.R. , Clish Clary B. , Rhee Eugene P. 
Published: June 2021

The delta‐5 desaturase (D5D) and delta‐6 desaturase (D6D), encoded by FADS1 and FADS2 respectively, are required for the synthesis of highly unsaturated fatty acids (HUFAs). Genetic variants associated with FADS1 and FADS2 expression are associated with HUFA content in circulating lipids, as well as fasting glucose, height and weight, and risk of colon and laryngeal cancer. Why genetic variation in HUFA synthesis has such a broad impact on human metabolic and proliferative phenotypes is unknown. Here, we show that HUFA synthesis is a mechanism for cytosolic NAD+ recycling that permits ongoing glycolysis. Consistent with this, lowering the cytosolic NAD+/NADH ratio via inhibition of mitochondrial respiration increased D5D and D6D activity in vitro and in vivo. Conversely, increasing the cytosolic NAD+/NADH ratio via expression of an NADH oxidase or activation of lactate dehydrogenase decreased D5D and D6D activity. Increasing D5D and D6D expression increased cytosolic NAD+/NADH, whereas reduced expression or inhibition of D5D and D6D decreased cytosolic NAD+/NADH and increased lactate production. Inhibition of D5D and D6D also reduced cell proliferation, an effect that was reversed by boosting cytosolic NAD+ but not with HUFA end‐product supplementation. Finally, we show that the type 2 diabetes risk haplotype in SLC16A11, which reduces pyruvate transport, also increases D5D and D6D activity, demonstrating the relevance of our findings to human disease. These results outline a novel link between glycolysis and HUFA desaturation mediated by cytosolic NAD+, and provide new insight on how D5D and D6D activity may impact glycemic, growth, and cancer traits in humans.Support or Funding InformationThis work was supported by NIH U01 DK060990 and the Extramural Grant Program of Satellite Health Care, a not‐for‐profit renal care provider.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Thioesterase superfamily member 2 (Them2) Regulates Fatty Acid Partitioning Between Oxidative and Secretory Pathways in the Liver
Authors: Alves‐Bezerra Michele , Li Yingxia , Cohen David E. 
Published: June 2021

Them2 (synonym: Acyl‐CoA thioesterase 13) is a mitochondria‐associated long‐chain acyl‐CoA thioesterase that is abundant in the liver and oxidative tissues. Evidence from whole‐body knockout mice suggests that Them2 prevents diet‐induced hepatosteatosis and improves hepatic glucose homeostasis. In cultured hepatocytes, Them2 promotes fatty acid oxidation and decreases lipogenesis. However, because it also suppresses thermogenesis in brown adipose tissue by limiting fatty acid oxidation, the true contribution to fatty acid metabolism of Them2 in the liver remains unclear. In order to evaluate the role of Them2 in liver to fatty acid metabolism, we created Them2 liver‐specific knockout (L‐Them2−/−) mice, which were fed chow or high fat diet for 12 weeks. L‐Them2−/− mice exhibited similar weight gain, body mass composition and glucose homeostasis in comparison to control animals. Whereas the rates of fatty acid uptake, de novo fatty acid synthesis, and hepatic concentrations of free fatty acids were unchanged, hepatic fatty acid oxidation was increased by 30% in chow‐fed L‐Them2−/− mice. In the absence of changes in steady concentrations of hepatic triglyceride and glycerolipid synthetic rates, a reduction in plasma triglyceride concentrations was observed upon hepatic Them2 ablation (38 and 43% decrease in chow and high fat fed, respectively). This was associated with a reduction in plasma VLDL‐triglyceride concentrations (29 and 9% in chow and high fat fed mice, respectively). Chow fed L‐Them2−/− mice also exhibited a 26% reduction in plasma apoB100 concentrations and a marked (70%) reduction in hepatic VLDL‐triglyceride secretion rates. Taken together, these data suggest that hepatic Them2 functions to direct fatty acids towards triglyceride incorporation into VLDL particles for secretion and away from mitochondrial β‐oxidation, thereby sustaining the export of lipids from the liver to the plasma and peripheral tissues. We speculate that Them2 in the liver plays a key role in determining the metabolic fates of fatty acids in response to nutritional status and metabolic demands.Support or Funding InformationThis work was supported by NIH R37 DK048873 and R01 DK056626 to D.E.C. M.A.‐B. was the recipient of a NASH Fatty Liver Disease Postdoctoral Research Fellowship Award from the American Liver Foundation.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Lysozyme over‐expression during nerve injury excites Aδ & C fibres in a fibre specific manner to incite neuropathic pain
Authors: SUROLIA AVADHESHA , Yadav Saurabh 
Published: June 2021

Human lysozyme is one of the most extensively studied proteins yet its exact physiological functions still remain a mystery. Here, we highlight a hitherto unrecognized role of lysozyme in neuropathic pain and neuronal excitability. Injection of lysozyme alone in healthy rats leads to heightened sensitivity in them towards both mechanical and thermal pain stimuli. Also, in rat models of neuropathic pain, lysozyme is over – expressed and its down – regulation by siRNA or inhibition of its activity by its disaccharide inhibitor ‐ chitobiose relieves pain confirming a causal role of lysozyme in neuropathic pain. Moreover, as the catalytically incompetent lysozyme or its chemically inhibited counterparts fail to provoke pain indicate that it deploys its catalytic site for eliciting pain. Bath application of lysozyme remarkably increased both the spontaneous excitatory potentials and currents (sEPSPs & sEPSCs) and the amplitudes of afferent mediated evoked excitatory synaptic inputs (eFPSPs & eEPSCs) in Aδ fibres in a fibre specific manner in the dorsal horn neurons. It also increased paired pulsed ratio only in the C‐fibres. When complexed with chitobiose it does not lead to any change in neuronal excitability. Thus, lysozyme excites neurons by deploying its catalytic region in a fibre specific manner. Further, we show that it deploys its catalytic site to recruit Annexin A2 to transduce TLR4→NFkβ signaling pathway which may culminate in the fusion of neurotransmitter vesicles at the synapse to manifest neuronal excitability and eventually pain. Thus, glycan inhibitors of lysozyme and antagonists of the pathway recruited by it to inflict pain pave not only the way for novel approaches for dissecting the molecular mechanism of neuropathic pain but also for treating this unmet medical need efficaciously.Support or Funding InformationCouncil of Scientific and Industrial Research, India to ASThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Glycomics Studies on Nematodes Elucidate Conserved Functional Epitopes and Biosynthetic Pathways
Authors: Yan Shi , Vanbeselaere Jorick , Jin Chunsheng , Joachim Anja , Paschinger Katharina , Wilson Iain B. H. 
Published: June 2021

Nematodes constitute a large number of different species on earth and some are disease‐causing parasites of mammals. Glycoproteins synthesised by nematodes are decorated with a different set of glycan structures as compared to the ones produced by mammals. During the course of parasite‐host interactions, nematode glycans could trigger or modulate host immune responses. To better understand the conserved N‐glycosylation machinery in nematodes, we use the free‐living Caenorhabditis elegans as a model; double/triple mutants were generated to investigate the function of genes which are involved in N‐glycan biosynthesis. N‐glycans of C. elegans as well as parasitic nematodes were released, either enzymatically or chemically, fluorescently labelled and analysed in a great detail using off‐line HPLC‐MALDI‐TOF‐MS in combination with exo‐glycosidases and chemical treatments. Furthermore, a number of fucosyltransferases (FUTs), hexosaminidases and N‐acetylglucosyltransferases were cloned and recombinantly expressed so that their enzymatic activities were studied in vitro by glycan remodelling. A range of conserved functional epitopes on N‐glycans were characterised in C. elegans wild‐type and mutant strains and were also identified in parasitic species, such as Oesophagostomum dentatum and Haemonchus contortus; this includes different types of Gal‐Fuc modifications of the chitobiose core and phosphorylcholine substitution on the N‐acetylhexosamine residues of the antennae. The functions of three core‐modifying FUTs were elucidated by in vitro and glycomic analyses. Moreover, the rice PNGase A or hydrazine released more N‐glycans with complex core modifications, which are not observed before using traditional PNGase F and almond PNGase A. These data expand our knowledge on nematode N‐glycosylation, particularly the plasticity in producing rare structures when a biosynthetic pathway is disturbed. Identification of nematode‐specific glyco‐epitopes would facilitate the design of novel strategies for diagnosing parasitic infections and aid engineering of glyco‐vaccines in the future.Support or Funding InformationThe Austrian Fonds zur Förderung der wissenschaftlichen Forschung (FWF; grants P30021 to S.Y., P21946 and P25058 to K.P. and P23922 and P29466 to I.B.H.W.)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Dissecting difference in heterologous protein secretion titer by Type III secretion system between strains of Salmonella enterica
Authors: Wong Han Teng , Tullman‐Ercek Danielle 
Published: June 2021

Type III secretion systems (T3SS) are complex macromolecular machines found in Gram‐negative bacteria. These bacteria utilize T3SS to facilitate microbe‐host interactions by translocating proteins, known as effectors, into the host cells. This provides an interesting system for engineering the selective translocation of proteins out of the bacterial cell. Secretion strategies have been useful in exporting proteins of biotechnological interest in systems such as yeast, insect cells and mammalian cells. Moreover, bacteria fermentations are faster and cheaper.In our lab, we make use of the SPI‐1 T3SS in Salmonella enterica serovar Typhimurium for protein export. Because the Salmonella SPI‐1 is not an essential metabolic pathway, we can harness it for heterologous protein secretion without affecting cell viability. Using secretion assays based on western blotting and a split GFP system, we were able to determine that the DW01 strain secretes ~20% more proteins than the LT2 strain.In order to determine the genetic basis for the differences in secretion titer, we sequenced the genomes of both strains using next generation sequencing to determine single nucleotide variants and indels unique to DW01. Some of the mutations were then further verified by Sanger sequencing. The alleles for each locus are then exhaustively swapped in both strain using the recombineering method established by the Court lab. This allows us to determine the contribution of each alleles at every locus to the increased secretion observed in DW01. Other phenotypic differences are also characterized.Through this work, we also identify genes outside of the SPI‐1 pathogenicity island that can modulate the heterologous protein secretion capability of S. enterica. Taken together, these experiments provide us with more tools to further increase the titer and achieve the industrial standards of >1g/L of protein.Support or Funding InformationH.T.W. is funded by A*STAR. L.B. is funded by NSF GRFP. This work is funded by NSF CBET grant number 1706125.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Oroxylin A prevents cardiac hypertrophy and dysfunction as a modulator of mitochondrial protein acetylation
Authors: Aguilar‐Sáenz Alejandro , Treviño‐Saldaña Niria , Oropeza‐Almazán Yuriana , García‐Rivas Gerardo 
Published: June 2021

Cardiac hypertrophy and remodeling are both well‐known consequences mediated by increased levels of Angiotensin II (Ang II) as a compensatory mechanism in non‐ischemic HF. In this sense, mitochondrial protein hyper‐acetylation and ROS production that induce mitochondrial dysfunction have previously been associated with this condition. Oroxylin A (OA) is a methylated flavone found on the root of Scutellaria baicalensis known for its antioxidant properties, and as a modulator of mitochondrial deacetylase activity. Nevertheless, OA effects have not been explored in cardiac remodeling mediated by exacerbated ROS production and mitochondrial hyper‐acetylation. Therefore, we explore the potential cardioprotective effect of OA in an in vitro model of cardiac hypertrophy induced by Ang II treatment in H9c2 myocytes. We found that OA reverted completely the Ang II mediated hypertrophic and cell death effect. Mitochondrial acetylation profile and sirtuin3 expression analyzed by western blot showed that Ang II promotes ~2‐fold increase in protein acetylation; however, OA pre‐treatment abrogates Ang II‐induced hyper‐acetylation in a dose‐dependent fashion. Remarkably, we found that the OA pre‐treatment prevents mitochondrial dysfunction by decreasing significantly permeability transition susceptibility and membrane potential depolarization. These results were consistent with a decrease in apoptosis, determined by caspase 9 and 3,7 activity. Overall, these findings suggest that OA promotes sirtuin3 activation, targeting pivot mitochondrial proteins. Accordingly, we evaluated the cardioprotective effect of OA in an in vivo model of HF induced by AngII+L‐NAME. In this model, we found an increased mitochondrial acetylation in the myocardium and found that OA was capable of prevent cardiac hypertrophy and dysfunction. Taken together, our results suggest that OA is a novel strategy to treat cardiac dysfunction in HF.Support or Funding InformationThis work was partially supported by Xignus Research Foundation as well endowed Chair in Cardiology/Grupo de Enfoque Medicina Cardiovascular Tec de Monterrey, CONACYT Grant CB‐256577, Fronteras de la Ciencias 0682 (Gerardo García‐Rivas), and Red Temática Farmoquímicos del CONACYT.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Expression of Fusion Proteins in Different Subpopulations of Cardiac Mitochondria
Authors: Guzmán‐Hernández Roberto , Parodi‐Rullán Rebecca M. , Chapa‐Dubocq Xavier , Jang Sehwan , Javadov Sabzali 
Published: June 2021

BackgroundMitochondrial dynamics including fission and fusion, along with mitophagy, play a vital role in the maintenance of the structural and functional integrity and number of mitochondria in the cell. These processes work to sustain the mitochondrial quality in the cell, in order to ensure optimal functioning of the cell. Mitochondrial fission and fusion are mediated by several proteins; including dynamin‐related 1 and fission protein 1 for fission and, optic atrophy type 1 (OPA1) and mitofusins 1 (Mfn1) and 2 (Mfn2) for fusion. Fusion proteins (OPA1, Mfn1 and Mfn2) promote fusion of two mitochondria into one, thereby eliminating dysfunctional mitochondria and thus, maintaining their normal morphology, content, and function, as well as the quality of the mitochondria in different subcellular compartments. The mitochondria in cardiomyocytes can be categorized in subpopulations based on their structural and physiological differences: subsarcolemmal mitochondria (SSM), which are found underneath the sarcolemma; interfibrillar mitochondria (IFM), localized between the myofibrils; and perinuclear mitochondria, which reside near the nuclear poles. Connexin‐43, a transmembrane protein responsible for the formation of gap junctions, can be used to differentiate between the SSM and IFM. In this project, we aim to study the role of mitochondrial fusion proteins between these two populations of mitochondria.HypothesisExpression of fusion proteins are different between the SSM and IFM in intact rat hearts.MethodsMitochondria were isolated from Sprague‐Dawley male rat hearts (n=6). Mitochondrial proteins were visualized by SDS‐PAGE followed by western blot analysis using antibodies against OPA1, Mfn1, and Mfn2.ResultsThe level of connexin‐43 was 95% (P<0.001) lower in IFM compared to SSM. Analysis of fusion proteins revealed that IFM contained 10% (P<0.47), 88% (P<0.001) and 24% (P<0.31) less OPA‐1, Mfn1 and Mfn2, respectively, when compared to SSM. Short and long isoforms of OPA‐1 were 70% (P< 0.002) and 32% (P<0.05) lower in IFM compared to SSM.ConclusionLower expression of fusion proteins in IFM can explain differences in functional parameters between two mitochondrial subpopulations in the heart.Support or Funding InformationSupported by the NHLBI NIH grants SC1HL118669 (S.J.) and 1 R25 HL115473‐01 (R.G‐H.).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.