630 results match your criteria cholesterol sensing

Polypyrrole and enzyme free cholesterol flakes based composite: Selective determination of theophylline.

J Pharm Biomed Anal 2021 Apr 6;199:114065. Epub 2021 Apr 6.

Polymer Electronics Lab, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi, 630 003, Tamil Nadu, India. Electronic address:

In the present work, we demonstrated the non-enzymatic theophylline (TP) detection using nanostructured Polypyrrole (Ppy) and Cholesterol (Ch) flakes coordinated nanocomposite coated on Glassy Carbon Electrode. The higher active surface area and good mechanical stability of the Ppy integrated Ch composite exhibited better oxidation towards TP. The electron transfer across hydrogen bonding is of fundamental importance in enhancing the biochemical process in this biosensor system. Read More

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Mechanistic Aspects of the Evolution of 3D Cholesterol Crystallites in a Supported Lipid Membrane via a Quartz Crystal Microbalance with Dissipation Monitoring.

Langmuir 2021 Apr 9. Epub 2021 Apr 9.

School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore.

The irreversible formation of cholesterol monohydrate crystals within biological membranes is the leading cause of various diseases, including atherosclerosis. Understanding the process of cholesterol crystallization is fundamentally important and could also lead to the development of improved therapeutic strategies. This has driven several studies investigating the effect of the environmental parameters on the induction of cholesterol crystallite growth and the structure of the cholesterol crystallites, while the kinetics and mechanistic aspects of the crystallite formation process within lipid membranes remain poorly understood. Read More

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Interaction of Full-Length Glycosylphosphatidylinositol-Anchored Proteins with Serum Proteins and Their Translocation to Cells In Vitro Depend on the (Pre-)Diabetic State in Rats and Humans.

Biomedicines 2021 Mar 10;9(3). Epub 2021 Mar 10.

Institute for Diabetes and Obesity (IDO), Helmholtz Diabetes Center (HDC) at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, 85764 Oberschleissheim, Germany.

Glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs), which are anchored at the surface of mammalian cultured and tissue cells through a carboxy-terminal GPI glycolipid, are susceptible to release into incubation medium and (rat and human) blood, respectively, in response to metabolic stress and ageing. Those GPI-APs with the complete GPI still attached form micelle-like complexes together with (lyso)phospholipids and cholesterol and are prone to degradation by serum GPI-specific phospholipase D (GPLD1), as well as translocation to the surface of acceptor cells in vitro. In this study, the interaction of GPI-APs with GPLD1 or other serum proteins derived from metabolically deranged rat and humans and their translocation were measured by microfluidic chip- and surface acoustic wave-based sensing of micelle-like complexes reconstituted with model GPI-APs. Read More

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Role of Bile Acids in the Regulation of Food Intake, and Their Dysregulation in Metabolic Disease.

Nutrients 2021 Mar 28;13(4). Epub 2021 Mar 28.

Adelaide Medical School, Center of Research Excellence (CRE) in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide 5005, Australia.

Bile acids are cholesterol-derived metabolites with a well-established role in the digestion and absorption of dietary fat. More recently, the discovery of bile acids as natural ligands for the nuclear farnesoid X receptor (FXR) and membrane Takeda G-protein-coupled receptor 5 (TGR5), and the recognition of the effects of FXR and TGR5 signaling have led to a paradigm shift in knowledge regarding bile acid physiology and metabolic health. Bile acids are now recognized as signaling molecules that orchestrate blood glucose, lipid and energy metabolism. Read More

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Fasting and fasting-mimicking treatment activate SIRT1/LXRα and alleviate diabetes-induced systemic and microvascular dysfunction.

Diabetologia 2021 Mar 26. Epub 2021 Mar 26.

Department of Physiology, Michigan State University, East Lansing, MI, USA.

Aims/hypothesis: Homo sapiens evolved under conditions of intermittent food availability and prolonged fasting between meals. Periods of fasting are important for recovery from meal-induced oxidative and metabolic stress, and tissue repair. Constant high energy-density food availability in present-day society contributes to the pathogenesis of chronic diseases, including diabetes and its complications, with intermittent fasting (IF) and energy restriction shown to improve metabolic health. Read More

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Functionalised Graphene Quantum Dots for Cholesterol Detection in Human Blood Serum.

J Fluoresc 2021 May 24;31(3):847-852. Epub 2021 Mar 24.

Laboratory for Polymer Analysis, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, 695012, India.

The varied applications of nanotechnology have paved way for several breakthroughs in the realm of biomedical technology. In this challenging era when illness multiplies, timely and accurate disease diagnosis is very important. Thus, well founded novel approaches matter very much in areas like disease diagnosis and monitoring. Read More

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Cholesterol-lowering activity of natural mono- and sesquiterpenoid compounds in essential oils: A review and investigation of mechanisms using in silico protein-ligand docking.

Phytother Res 2021 Mar 22. Epub 2021 Mar 22.

Science & Education, doTERRA International LLC, 389 1300 W, Pleasant Grove, Utah, 84062, USA.

Mono- and sesquiterpenoids are the main chemical constituents of essential oils. Essential oils and their constituents have received increasing attention for lipid-lowering properties in both cell and animal models. Despite the chemical diversity of essential oil compounds, the effects of many of these compounds on cholesterol metabolism are highly similar. Read More

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Activation of nuclear receptor PXR induces atherogenic lipids and PCSK9 through SREBP2-mediated mechanism.

Br J Pharmacol 2021 Mar 9. Epub 2021 Mar 9.

Research Unit of Biomedicine, University of Oulu, Oulu, Finland.

Background And Purpose: Many drugs and environmental contaminants induce hypercholesterolemia and promote the risk of atherosclerotic cardiovascular disease. The mechanisms involved are poorly defined precluding efficient prediction and prevention. We tested the hypothesis that pregnane X receptor (PXR), a xenobiotic-sensing nuclear receptor, regulates the level of circulating atherogenic lipids in humans and utilized mouse experiments to identify the mechanisms involved. Read More

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Dietary Geranylgeranyl Pyrophosphate Counteracts the Benefits of Statin Therapy in Experimental Pulmonary Hypertension.

Circulation 2021 Mar 4. Epub 2021 Mar 4.

Department of Pathophysiology, School of Basic Medicine; Key Laboratory of Pulmonary Diseases of Ministry of Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

The mevalonate pathway generates endogenous cholesterol and intermediates including geranylgeranyl pyrophosphate (GGPP). By reducing GGPP production, statins exert pleiotropic or cholesterol-independent effects. The potential regulation of GGPP homeostasis through dietary intake and the interaction with concomitant statin therapy is unknown. Read More

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GlnR Regulates the Glyoxylate Cycle and the Methylcitrate Cycle on Fatty Acid Metabolism by Repressing Transcription.

Front Microbiol 2021 3;12:603835. Epub 2021 Feb 3.

Institute of Engineering Biology and Health, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China.

(), along with its pathogenic counterpart (), utilizes fatty acids and cholesterol as important carbon and energy sources during the persistence within host cells. As a dual-functional enzyme in the glyoxylate cycle and the methylcitrate cycle, isocitrate lyase (ICL, encoded by or ) is indispensable for the growth of and on short-chain fatty acids. However, regulation of in mycobacteria in response to nutrient availability remains largely unknown. Read More

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February 2021

Antidepressant drugs act by directly binding to TRKB neurotrophin receptors.

Cell 2021 Mar 18;184(5):1299-1313.e19. Epub 2021 Feb 18.

Neuroscience Center-HILIFE, University of Helsinki, Helsinki, Finland. Electronic address:

It is unclear how binding of antidepressant drugs to their targets gives rise to the clinical antidepressant effect. We discovered that the transmembrane domain of tyrosine kinase receptor 2 (TRKB), the brain-derived neurotrophic factor (BDNF) receptor that promotes neuronal plasticity and antidepressant responses, has a cholesterol-sensing function that mediates synaptic effects of cholesterol. We then found that both typical and fast-acting antidepressants directly bind to TRKB, thereby facilitating synaptic localization of TRKB and its activation by BDNF. Read More

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Molecular basis of accessible plasma membrane cholesterol recognition by the GRAM domain of GRAMD1b.

EMBO J 2021 Mar 19;40(6):e106524. Epub 2021 Feb 19.

Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Cholesterol is essential for cell physiology. Transport of the "accessible" pool of cholesterol from the plasma membrane (PM) to the endoplasmic reticulum (ER) by ER-localized GRAMD1 proteins (GRAMD1a/1b/1c) contributes to cholesterol homeostasis. However, how cells detect accessible cholesterol within the PM remains unclear. Read More

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RegX3-Mediated Regulation of Methylcitrate Cycle in .

Front Microbiol 2021 2;12:619387. Epub 2021 Feb 2.

Institute of Engineering Biology and Health, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, China.

is a global human pathogen that infects macrophages and can establish a latent infection. Emerging evidence has established the nutrients metabolism as a key point to study the pathogenesis of and host immunity. It was reported that fatty acids and cholesterol are the major nutrient sources of in the period of infection. Read More

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February 2021

A highly-specific photoelectrochemical platform based on carbon nanodots and polymers functionalized organic-inorganic perovskite for cholesterol sensing.

Talanta 2021 Apr 27;225:122050. Epub 2020 Dec 27.

School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, China. Electronic address:

Herein, we reported the introduction of carbon nanodots (CNDs) and polyvinylidene fluoride (PVDF) as additives into perovskite CHNHPbI through in situ synthesis to prepare PVDF-CHNHPbI@CNDs composite, which demonstrated improved water tolerance and mechanical stability. The application of PVDF-CHNHPbI@CNDs for photoelectrochemical sensing was then explored. A molecularly imprinted polymer (MIP) that could specifically recognize cholesterol (CHO) was anchored to PVDF-CHNHPbI@CNDs via a simple thermal polymerization process, followed by elution with hexane. Read More

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Nanocomposite of CuInS/ZnS and Nitrogen-Doped Graphene Quantum Dots for Cholesterol Sensing.

ACS Omega 2021 Jan 13;6(3):2167-2176. Epub 2021 Jan 13.

Nanotechnology and Composite Materials Department, Institute of New Materials and Advanced Technology, City of Scientific Research and Technological Applications (SRTA-City), New Borg El Arab City, P.O. Box, 21934 Alexandria, Egypt.

In this paper, nitrogen graphene quantum dots (N-GQDs) and copper indium sulfide/zinc sulfide (CIS/ZnS) QDs were synthesized via facile hydrothermal and aqueous solution routes, respectively. Herein, a fluorescent nanocomposite has been synthesized between N-GQDs and CIS/ZnS QDs in an aqueous phase. This nanocomposite was characterized by photoluminescence, Raman, and ultraviolet-visible (UV-vis) spectroscopies, high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD). Read More

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January 2021

Paper Microfluidics and Tailored Gold Nanoparticles for Nonenzymatic, Colorimetric Multiplex Biomarker Detection.

ACS Appl Mater Interfaces 2021 Jan 15;13(3):3576-3590. Epub 2021 Jan 15.

CENIMAT|i3N, Departamento de Ciência de Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa and CEMOP/UNINOVA, Campus da Caparica, 2829-516 Caparica, Portugal.

The plasmonic properties of gold nanoparticles (AuNPs) are a promising tool to develop sensing alternatives to traditional, enzyme-catalyzed reactions. The need for sensing alternatives, especially in underdeveloped areas of the world, has given rise to the application of nonenzymatic sensing approaches paired with cellulosic substrates to biochemical analysis. Herein, we present three individual, low-step, wet-chemistry, colorimetric assays for three target biomarkers, namely, glucose, uric acid, and free cholesterol, relevant in diabetes control and their translation into paper-based assays and microfluidic platforms for multiplexed analysis. Read More

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January 2021

A structure of human Scap bound to Insig-2 suggests how their interaction is regulated by sterols.

Science 2021 03 14;371(6533). Epub 2021 Jan 14.

Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.

The sterol regulatory element-binding protein (SREBP) pathway controls cellular homeostasis of sterols. The key players in this pathway, Scap and Insig-1 and -2, are membrane-embedded sterol sensors. The 25-hydroxycholesterol (25HC)-dependent association of Scap and Insig acts as the master switch for the SREBP pathway. Read More

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Deficiency of circadian gene cryptochromes in bone marrow-derived cells protects against atherosclerosis in LDLR mice.

FASEB J 2021 Feb;35(2):e21309

Department of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan City, Taiwan.

Cryptochromes are photoreceptors that mediate the circadian entrainment by light in plants and animals. They are also involved in magnetic field sensing in some animals. Recent studies suggest that cryptochromes play an essential role in metabolism and cardiovascular disease. Read More

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February 2021

Targeted Solvatochromic Fluorescent Probes for Imaging Lipid Order in Organelles under Oxidative and Mechanical Stress.

J Am Chem Soc 2021 Jan 8;143(2):912-924. Epub 2021 Jan 8.

Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 Route du Rhin, 67401 Illkirch, France.

Biomembranes constitute a basis for all compartments of live cells, and therefore, the monitoring of their lipid organization is essential for understanding cell status and activity. However, the sensing and imaging of lipid organization specifically in different organelles of live cells remain challenging. Here, we designed an array of solvatochromic probes based on Nile Red bearing ligands for specific targeting of the endoplasmic reticulum, mitochondria, lysosomes, Golgi apparatus, plasma membranes, and lipid droplets. Read More

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January 2021

Mesoporous TiO-based architectures as promising sensing materials towards next-generation biosensing applications.

J Mater Chem B 2021 02;9(5):1189-1207

Department of Engineering Physics, Faculty of Industrial Technology, Institute of Technology Bandung, Ganesha 10, Bandung 40132, Indonesia. and Research Center for Nanosciences and Nanotechnology (RCNN), Institute of Technology Bandung, Bandung 40132, Indonesia.

In the past two decades, mesoporous TiO2 has emerged as a promising material for biosensing applications. In particular, mesoporous TiO2 materials with uniform, well-organized pores and high surface areas typically exhibit superior biosensing performance, which includes high sensitivity, broad linear response, low detection limit, good reproducibility, and high specificity. Therefore, the development of biosensors based on mesoporous TiO2 has significantly intensified in recent years. Read More

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February 2021

Alcoholic and Non-Alcoholic Beer Modulate Plasma and Macrophage microRNAs Differently in a Pilot Intervention in Humans with Cardiovascular Risk.

Nutrients 2020 Dec 28;13(1). Epub 2020 Dec 28.

Nutritional Genomics and Epigenomics Group, IMDEA Food, CEI UAM + CSIC, 28049 Madrid, Spain.

Beer is a popular beverage and some beneficial effects have been attributed to its moderate consumption. We carried out a pilot study to test if beer and non-alcoholic beer consumption modify the levels of a panel of 53 cardiometabolic microRNAs in plasma and macrophages. Seven non-smoker men aged 30-65 with high cardiovascular risk were recruited for a non-randomised cross-over intervention consisting of the ingestion of 500 mL/day of beer or non-alcoholic beer for 14 days with a 7-day washout period between interventions. Read More

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December 2020

Maturation of Monocyte-Derived DCs Leads to Increased Cellular Stiffness, Higher Membrane Fluidity, and Changed Lipid Composition.

Front Immunol 2020 27;11:590121. Epub 2020 Nov 27.

Laboratory of Dendritic Cell Biology, Department of Dermatology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University Hospital Erlangen, Erlangen, Germany.

Dendritic cells (DCs) are professional antigen-presenting cells of the immune system. Upon sensing pathogenic material in their environment, DCs start to mature, which includes cellular processes, such as antigen uptake, processing and presentation, as well as upregulation of costimulatory molecules and cytokine secretion. During maturation, DCs detach from peripheral tissues, migrate to the nearest lymph node, and find their way into the correct position in the net of the lymph node microenvironment to meet and interact with the respective T cells. Read More

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November 2020

Image-based screen capturing misfolding status of Niemann-Pick type C1 identifies potential candidates for chaperone drugs.

PLoS One 2020 14;15(12):e0243746. Epub 2020 Dec 14.

Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.

Niemann-Pick disease type C is a rare, fatal neurodegenerative disorder characterized by massive intracellular accumulation of cholesterol. In most cases, loss-of-function mutations in the NPC1 gene that encodes lysosomal cholesterol transporter NPC1 are responsible for the disease, and more than half of the mutations are considered to interfere with the biogenesis or folding of the protein. We previously identified a series of oxysterol derivatives and phenanthridine-6-one derivatives as pharmacological chaperones, i. Read More

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January 2021

NPC1-mTORC1 Signaling Couples Cholesterol Sensing to Organelle Homeostasis and Is a Targetable Pathway in Niemann-Pick Type C.

Dev Cell 2021 Feb 11;56(3):260-276.e7. Epub 2020 Dec 11.

Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; The Paul F. Glenn Center for Aging Research at the University of California, Berkeley, Berkeley, CA 94720, USA. Electronic address:

Lysosomes promote cellular homeostasis through macromolecular hydrolysis within their lumen and metabolic signaling by the mTORC1 kinase on their limiting membranes. Both hydrolytic and signaling functions require precise regulation of lysosomal cholesterol content. In Niemann-Pick type C (NPC), loss of the cholesterol exporter, NPC1, causes cholesterol accumulation within lysosomes, leading to mTORC1 hyperactivation, disrupted mitochondrial function, and neurodegeneration. Read More

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February 2021

Design of Nanosystems for the Delivery of Quorum Sensing Inhibitors: A Preliminary Study.

Molecules 2020 Nov 30;25(23). Epub 2020 Nov 30.

Department of Chemical and Pharmaceutical Sciences, University of Ferrara, I-44121 Ferrara, Italy.

Biofilm production is regulated by the Quorum Sensing system. Nowadays, Quorum Sensing represents an appealing target to design new compounds to increase antibiotics effects and avoid development of antibiotics multiresistance. In this research the use of liposomes to target two novel synthetic biofilm inhibitors is presented, focusing on a preformulation study to select a liposome composition for in vitro test. Read More

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November 2020

Age-related changes in PD-1 expression coincide with increased cytotoxic potential in Vδ2 T cells during infancy.

Cell Immunol 2021 Jan 13;359:104244. Epub 2020 Nov 13.

Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States. Electronic address:

Human Vγ9Vδ2 T cells respond to several diverse pathogens by sensing microbial cholesterol intermediates. Unlike CD4 T cells, they are poised for rapid Th1-like responses even before birth, which allows them to play a key role in the first line of defense against pathogens in early life. However, their regulation and functional maturation during infancy (in particular the acquisition of cytotoxic potential) remain understudied. Read More

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January 2021

Functional Peroxisomes Are Essential for Efficient Cholesterol Sensing and Synthesis.

Front Cell Dev Biol 2020 6;8:560266. Epub 2020 Nov 6.

Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland.

Cholesterol biosynthesis is a multi-step process involving several subcellular compartments, including peroxisomes. Cells adjust their sterol content by both transcriptional and post-transcriptional feedback regulation, for which sterol regulatory element-binding proteins (SREBPs) are essential; such homeostasis is dysregulated in peroxisome-deficient knockout mice. Here, we compared the regulation of cholesterol biosynthesis in Chinese hamster ovary (CHO-K1) cells and in three isogenic peroxisome-deficient CHO cell lines harboring gene mutations. Read More

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November 2020

On-Site Colorimetric Detection of Cholesterol Based on Polypyrrole Nanoparticles.

ACS Appl Mater Interfaces 2020 Dec 25;12(49):54426-54432. Epub 2020 Nov 25.

Molecular Science and Biomedicine Laboratory, State Key Laboratory for Chemo/Bio-Sensing and Chemometrics, College of Biology College of Material Science and Engineering, College of Chemistry and Chemical Engineering, and Collaborative Research Center of Molecular Engineering for Theranostics, Hunan University, Changsha 410082, China.

Herein, we report a facile method for cholesterol detection by coupling the peroxidase-like activity of polypyrrole nanoparticles (PPy NPs) and cholesterol oxidase (ChOx). ChOx can catalyze the oxidation of cholesterol to produce HO. Subsequently, PPy NPs, as a nanozyme, induce the reaction between HO and 3,3',5,5'-tetramethylbenzidine (TMB). Read More

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December 2020

Biofunctionalization of Water-Soluble poly(Phenylene Ethynylene)s.

ACS Appl Mater Interfaces 2020 Nov 15;12(47):53310-53317. Epub 2020 Nov 15.

Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States.

We report the use of amide coupling chemistry to covalently link five different biofunctional groups onto an anionic water-soluble poly(phenylene ethynylene) (PPE) polymer. Two of the biofunctionalized PPEs are used in prototype applications, including pH sensing and flow cytometry labeling. The PPE is functionalized with carboxylate (R-CO) and sulfonate (R-SO) ionic groups. Read More

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November 2020

An autonomous, but INSIG-modulated, role for the Sterol Sensing Domain in mallostery-regulated ERAD of yeast HMG-CoA reductase.

J Biol Chem 2020 Nov 12. Epub 2020 Nov 12.

Division of Biological Sciences, University of California, San DIego, United States.

HMG-CoA reductase (HMGR) undergoes feedback-regulated degradation as part of sterol pathway control. Degradation of the yeast HMGR isozyme Hmg2 is controlled by the sterol pathway intermediate GGPP, which causes misfolding of Hmg2, leading to degradation by the HRD pathway; we call this process mallostery. We evaluated the role of the Hmg2 sterol sensing domain (SSD) in mallostery, as well as the involvement of the highly conserved INSIG proteins. Read More

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November 2020