613 results match your criteria c-terminal halves

Compensation for the absence of the catalytically active half of DNA polymerase ε in yeast by positively selected mutations in CDC28.

Genetics 2021 Apr 12. Epub 2021 Apr 12.

Department of Genetics and Biotechnology, Saint-Petersburg State University, Saint-Petersburg, Russia, 199034.

Current eukaryotic replication models postulate that leading and lagging DNA strands are replicated predominantly by dedicated DNA polymerases. The catalytic subunit of the leading strand DNA polymerase ε, Pol2, consists of two halves made of two different ancestral B-family DNA polymerases. Counterintuitively, the catalytically active N-terminal half is dispensable, while the inactive C-terminal part is required for viability. Read More

View Article and Full-Text PDF

Stabilisation of half MCM ring by Cdt1 during DNA insertion.

Nat Commun 2021 03 19;12(1):1746. Epub 2021 Mar 19.

Institut d'Investigació Biomèdica de Girona Dr. Josep Trueta (IDIBGI), Parc Hospitalari Martí i Julià de Salt, Catalunya, Spain.

Origin licensing ensures precise once per cell cycle replication in eukaryotic cells. The Origin Recognition Complex, Cdc6 and Cdt1 load Mcm2-7 helicase (MCM) into a double hexamer, bound around duplex DNA. The complex formed by ORC-Cdc6 bound to duplex DNA (OC) recruits the MCM-Cdt1 complex into the replication origins. Read More

View Article and Full-Text PDF

Genetic analysis of the interaction between the N- and C-terminal halves of UNC-112 (kindlin).

MicroPubl Biol 2020 Dec 17;2020. Epub 2020 Dec 17.

Department of Pathology, Emory University, Atlanta, Georgia.

View Article and Full-Text PDF
December 2020

Differential Contribution of N- and C-Terminal Regions of HIF1α and HIF2α to Their Target Gene Selectivity.

Int J Mol Sci 2020 Dec 10;21(24). Epub 2020 Dec 10.

Research Unit, Hospital Santa Cristina, Research Institute Princesa (IP), Autonomous University of Madrid, 28009 Madrid, Spain.

Cellular response to hypoxia is controlled by the hypoxia-inducible transcription factors HIF1α and HIF2α. Some genes are preferentially induced by HIF1α or HIF2α, as has been explored in some cell models and for particular sets of genes. Here we have extended this analysis to other HIF-dependent genes using in vitro WT8 renal carcinoma cells and in vivo conditional -deficient mice models. Read More

View Article and Full-Text PDF
December 2020

Structure and drug binding of the SARS-CoV-2 envelope protein transmembrane domain in lipid bilayers.

Nat Struct Mol Biol 2020 12 11;27(12):1202-1208. Epub 2020 Nov 11.

Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.

An essential protein of the SARS-CoV-2 virus, the envelope protein E, forms a homopentameric cation channel that is important for virus pathogenicity. Here we report a 2.1-Å structure and the drug-binding site of E's transmembrane domain (ETM), determined using solid-state NMR spectroscopy. Read More

View Article and Full-Text PDF
December 2020

Structure and Drug Binding of the SARS-CoV-2 Envelope Protein in Phospholipid Bilayers.

Res Sq 2020 Sep 24. Epub 2020 Sep 24.

Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing COVID-19 pandemic. Successful development of vaccines and antivirals against SARS-CoV-2 requires a comprehensive understanding of the essential proteins of the virus. The envelope (E) protein of SARS-CoV-2 assembles into a cation-selective channel that mediates virus budding, release, and host inflammation response. Read More

View Article and Full-Text PDF
September 2020

Probing Vulnerability of the gp41 C-Terminal Heptad Repeat as Target for Miniprotein HIV Inhibitors.

J Mol Biol 2020 09 19;432(20):5577-5592. Epub 2020 Aug 19.

Departamento de Química Física, Instituto de Biotecnología e Unidad de Excelencia de Química Aplicada a Biomedicina y Medioambiente (UEQ), Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain. Electronic address:

One of the therapeutic strategies in HIV neutralization is blocking membrane fusion. In this process, tight interaction between the N-terminal and C-terminal heptad-repeat (NHR and CHR) regions of gp41 is essential to promote membranes apposition and merging. We have previously developed single-chain proteins (named covNHR) that accurately mimic the complete gp41 NHR region in its trimeric conformation. Read More

View Article and Full-Text PDF
September 2020

Insights Into the Mechanism of MCT8 Oligomerization.

J Endocr Soc 2020 Aug 18;4(8):bvaa080. Epub 2020 Jun 18.

Academic Center for Thyroid Diseases, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands.

Mutations in the thyroid hormone transporter monocarboxylate transporter 8 (MCT8) result in MCT8 deficiency, characterized by severe intellectual and motor disability. The MCT8 protein is predicted to have 12 transmembrane domains (TMDs) and is expressed as monomers, homodimers, and homo-oligomers. This study aimed to delineate the mechanism of MCT8 oligomerization. Read More

View Article and Full-Text PDF

Rational Design of Hypoallergenic Vaccines: Blocking IgE-binding to Polcalcin Using Allergen-specific IgG Antibodies.

Iran J Allergy Asthma Immunol 2020 Jun 23;19(3):276-288. Epub 2020 Jun 23.

Department of Microbiology and Parasitology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran.

Chenopodium album polcalcin (Che a 3) is characterized as a major cause of cross-reactivity inallergic patients to the Chenopodiaceae family. Therefore, the present study was conducted to develop a hypoallergenic Che a 3 derivatives as the candidate vaccine for type 1 allergy. Four derivatives were generated from Che a 3. Read More

View Article and Full-Text PDF

The N-terminal and C-terminal halves of histone H2A.Z independently function in nucleosome positioning and stability.

Genes Cells 2020 Aug 22;25(8):538-546. Epub 2020 Jul 22.

Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan.

Nucleosome positioning and stability affect gene regulation in eukaryotic chromatin. Histone H2A.Z is an evolutionally conserved histone variant that forms mobile and unstable nucleosomes in vivo and in vitro. Read More

View Article and Full-Text PDF

Structure and function of the calcium-selective TRP channel TRPV6.

J Physiol 2021 May 13;599(10):2673-2697. Epub 2020 Mar 13.

Department of Biochemistry and Molecular Biophysics, Columbia University, 650 West 168th Street, New York, NY, 10032, USA.

Epithelial calcium channel TRPV6 is a member of the vanilloid subfamily of TRP channels that is permeable to cations and highly selective to Ca ; it shows constitutive activity regulated negatively by Ca and positively by phosphoinositol and cholesterol lipids. In this review, we describe the molecular structure of TRPV6 and discuss how its structural elements define its unique functional properties. High Ca selectivity of TRPV6 originates from the narrow selectivity filter, where Ca ions are directly coordinated by a ring of anionic aspartate side chains. Read More

View Article and Full-Text PDF

Conformational and lipid bilayer-perturbing properties of Marburg virus GP2 segments containing the fusion loop and membrane-proximal external region/transmembrane domain.

Heliyon 2019 Dec 12;5(12):e03018. Epub 2019 Dec 12.

Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.

Fusion of host and viral membranes is a crucial step during infection by enveloped viruses. In the structurally-defined "class I″ viral glycoproteins, the formation of a highly stable α-helical bundle by the ectodomain of the fusion subunit (e.g. Read More

View Article and Full-Text PDF
December 2019

Linker Domains: Why ABC Transporters 'Live in Fragments no Longer'.

Trends Biochem Sci 2020 02 12;45(2):137-148. Epub 2019 Dec 12.

Pharmaceutical Sciences, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105-3678, USA.

ATP-binding cassette (ABC) transporters are membrane proteins present in all kingdoms of life. We have considered the disordered region that connects the N- and C-terminal halves in many eukaryotic ABC transporters, allowing all four consensus functional domains to be linked. The recent availability of structures of ABC transporters containing linker regions has allowed us to identify the start and end points of the connectors as well as hinting at their localisation. Read More

View Article and Full-Text PDF
February 2020

Comparative structure-function analysis of bromodomain and extraterminal motif (BET) proteins in a gene-complementation system.

J Biol Chem 2020 02 2;295(7):1898-1914. Epub 2019 Dec 2.

Division of Hematology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104. Electronic address:

The widely expressed bromodomain and extraterminal motif (BET) proteins bromodomain-containing protein 2 (BRD2), BRD3, and BRD4 are multifunctional transcriptional regulators that bind acetylated chromatin via their conserved tandem bromodomains. Small molecules that target BET bromodomains are being tested for various diseases but typically do not discern between BET family members. Genomic distributions and protein partners of BET proteins have been described, but the basis for differences in BET protein function within a given lineage remains unclear. Read More

View Article and Full-Text PDF
February 2020

Elucidating Carotenoid Biosynthetic Enzyme Localization and Interactions Using Fluorescent Microscopy.

Methods Mol Biol 2020 ;2083:223-234

Department of Biological Sciences, Lehman College, The City University of New York, Bronx, NY, USA.

Carotenoids are essential for survival of all plants, where these colorful pigments and derivatives are biosynthesized, as well as for humans and other species that obtain plant-derived carotenoids in their diets and rely upon them for vitamin biosynthesis or antioxidant actions. The plant carotenoid biosynthetic pathway consists of nuclear encoded enzymes that are imported into chloroplasts and other plastids. The pathway structural genes are known and have been targeted for metabolic engineering to improve carotenoid profiles or content. Read More

View Article and Full-Text PDF
January 2021

The Complex Fibrinogen Interactions of the Coagulases.

Front Cell Infect Microbiol 2019 16;9:106. Epub 2019 Apr 16.

Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX, United States.

The two coagulases, von Willebrand factor binding protein (vWbp) and Coagulase (Coa), are critical virulence factors in several animal models of invasive () infections. These proteins are part of an intricate system of proteins that uses to assemble a fibrinogen (Fg)/fibrin protective shield surrounding itself. This shield allows the microorganism to evade clearance by the host phagocytic cells. Read More

View Article and Full-Text PDF
December 2019

p27kip1 at the crossroad between actin and microtubule dynamics.

Cell Div 2019 1;14. Epub 2019 Apr 1.

1Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO), IRCCS, National Cancer Institute, 33081 Aviano, Italy.

The p27 protein, mainly known as a negative regulator of cell proliferation, has also been involved in the control of other cellular processes, including the regulation of cytoskeleton dynamics. Notably, these two functions involve distinct protein domains, residing in the N- and C-terminal halves, respectively. In the last two decades, p27 has been reported to interact with microtubule and acto-myosin cytoskeletons, both in direct and indirect ways, overall drawing a picture in which several factors play their role either in synergy or in contrast one with another. Read More

View Article and Full-Text PDF

Crystal structure of heme A synthase from .

Proc Natl Acad Sci U S A 2018 11 5;115(47):11953-11957. Epub 2018 Nov 5.

Department of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan;

Heme A is an essential cofactor for respiratory terminal oxidases and vital for respiration in aerobic organisms. The final step of heme A biosynthesis is formylation of the C-8 methyl group of heme molecule by heme A synthase (HAS). HAS is a heme-containing integral membrane protein, and its structure and reaction mechanisms have remained unknown. Read More

View Article and Full-Text PDF
November 2018

A Bioluminescent Cell Assay to Quantify Prion Protein Dimerization.

Sci Rep 2018 09 21;8(1):14178. Epub 2018 Sep 21.

German Center for Neurodegenerative Diseases (DZNE), Bonn, 53127, Germany.

The prion protein (PrP) is a cell surface protein that in disease misfolds and becomes infectious causing Creutzfeldt-Jakob disease in humans, scrapie in sheep, and chronic wasting disease in deer and elk. Little is known regarding the dimerization of PrP and its role in disease. We developed a bioluminescent prion assay (BPA) to quantify PrP dimerization by bimolecular complementation of split Gaussia luciferase (GLuc) halves that are each fused to PrP. Read More

View Article and Full-Text PDF
September 2018

The protein-specific activities of the transmembrane modules of Ptch1 and Ptch2 are determined by their adjacent protein domains.

J Biol Chem 2018 10 30;293(43):16583-16595. Epub 2018 Aug 30.

From the Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada

Signaling through the Hedgehog (Hh) pathway is mediated by the Patched (Ptch) family of proteins. Although the vertebrate Ptch proteins Ptch1 and Ptch2 harbor two closely related transmembrane modules related to sterol-sensing domains (SSDs), the role of these closely related receptors in the Hh pathway are not equivalent. Ptch1 is essential for development and appears to be the principal receptor mediating responses to Hh ligands, whereas Ptch2 is nonessential, and its role in Hh-signaling remains ambiguous. Read More

View Article and Full-Text PDF
October 2018

Identification of Novel Cryptic Multifunctional Antimicrobial Peptides from the Human Stomach Enabled by a Computational-Experimental Platform.

ACS Synth Biol 2018 09 20;7(9):2105-2115. Epub 2018 Aug 20.

Department of Biology , University of Naples Federico II , Naples 80126 , Italy.

Novel approaches are needed to combat antibiotic resistance. Here, we describe a computational-experimental framework for the discovery of novel cryptic antimicrobial peptides (AMPs). The computational platform, based on previously validated antimicrobial scoring functions, indicated the activation peptide of pepsin A, the main human stomach protease, and its N- and C-terminal halves as antimicrobial peptides. Read More

View Article and Full-Text PDF
September 2018

Crystal Structure of a ligand-bound LacY-Nanobody Complex.

Proc Natl Acad Sci U S A 2018 08 14;115(35):8769-8774. Epub 2018 Aug 14.

Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158;

The lactose permease of (LacY), a dynamic polytopic membrane transport protein, catalyzes galactoside/H symport and operates by an alternating access mechanism that exhibits multiple conformations, the distribution of which is altered by sugar-binding. Camelid nanobodies were made against a double-mutant Gly46 → Trp/Gly262 → Trp (LacY) that produces an outward-open conformation, as opposed to the cytoplasmic open-state crystal structure of WT LacY. Nanobody 9047 (Nb9047) stabilizes WT LacY in a periplasmic-open conformation. Read More

View Article and Full-Text PDF

Ensemble cryoEM elucidates the mechanism of insulin capture and degradation by human insulin degrading enzyme.

Elife 2018 03 29;7. Epub 2018 Mar 29.

Ben-May Institute for Cancer Research, The University of Chicago, Chicago, United States.

Insulin degrading enzyme (IDE) plays key roles in degrading peptides vital in type two diabetes, Alzheimer's, inflammation, and other human diseases. However, the process through which IDE recognizes peptides that tend to form amyloid fibrils remained unsolved. We used cryoEM to understand both the apo- and insulin-bound dimeric IDE states, revealing that IDE displays a large opening between the homologous ~55 kDa N- and C-terminal halves to allow selective substrate capture based on size and charge complementarity. Read More

View Article and Full-Text PDF

Split cGAL, an intersectional strategy using a split intein for refined spatiotemporal transgene control in .

Proc Natl Acad Sci U S A 2018 04 26;115(15):3900-3905. Epub 2018 Mar 26.

Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125;

Bipartite expression systems, such as the GAL4-UAS system, allow fine manipulation of gene expression and are powerful tools for interrogating gene function. Recently, we established cGAL, a GAL4-based bipartite expression system for transgene control in , where a single promoter dictates the expression pattern of a cGAL driver, which then binds target upstream activation sequences to drive expression of a downstream effector gene. Here, we report a split strategy for cGAL using the split intein gp41-1 for intersectional control of transgene expression. Read More

View Article and Full-Text PDF

Crystal structure of B-cell co-receptor CD19 in complex with antibody B43 reveals an unexpected fold.

Proteins 2018 05 10;86(5):495-500. Epub 2018 Mar 10.

Janssen Research and Development, LLC, 1400 McKean Road, Spring House, Pennsylvania, 19477.

CD19 is a transmembrane protein expressed on malignant B cells, but not in other lineages or other tissues, which makes it an attractive target for monoclonal antibody-mediated immunotherapy. Anti-CD19 antibody B43 was utilized in a bispecific T-cell engager (BiTE) blinatumomab that demonstrated potency for the treatment of relapsed acute lymphoblastic leukemia. To gain insight into the mechanism of action of the antibody, the crystal structure of B43 Fab was determined in complex with CD19 and in the unbound form. Read More

View Article and Full-Text PDF

Pacing across the membrane: the novel PACE family of efflux pumps is widespread in Gram-negative pathogens.

Res Microbiol 2018 Sep - Oct;169(7-8):450-454. Epub 2018 Feb 2.

Department of Chemistry and Biomolecular Science, Macquarie University, North Ryde, NSW, Australia.

The proteobacterial antimicrobial compound efflux (PACE) family of transport proteins was only recently described. PACE family transport proteins can confer resistance to a range of biocides used as disinfectants and antiseptics, and are encoded by many important Gram-negative human pathogens. However, we are only just beginning to appreciate the range of functions and the mechanism(s) of transport operating in these proteins. Read More

View Article and Full-Text PDF
November 2018

Stability and Water Accessibility of the Trimeric Membrane Anchors of the HIV-1 Envelope Spikes.

J Am Chem Soc 2017 12 4;139(51):18432-18435. Epub 2017 Dec 4.

Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School , Boston, Massachusetts 02115, United States.

HIV-1 envelope spike (Env) is a type I membrane protein that mediates viral entry. Recent studies showed that its transmembrane domain (TMD) forms a trimer in lipid bilayer whose structure has several peculiar features that remain difficult to explain. One is the presence of an arginine R696 in the middle of the TM helix. Read More

View Article and Full-Text PDF
December 2017

Propensity for cis-Proline Formation in Unfolded Proteins.

Chembiochem 2018 01 16;19(1):37-42. Epub 2017 Nov 16.

Laboratory of Chemical Physics, National Institutes of Health, 5 Memorial Drive, Bethesda, MD, 20892, USA.

In unfolded proteins, peptide bonds involving Pro residues exist in equilibrium between the minor cis and major trans conformations. Folded proteins predominantly contain trans-Pro bonds, and slow cis-trans Pro isomerization in the unfolded state is often found to be a rate-limiting step in protein folding. Moreover, kinases and phosphatases that act upon Ser/Thr-Pro motifs exhibit preferential recognition of either the cis- or trans-Pro conformer. Read More

View Article and Full-Text PDF
January 2018

Identification of a Novel O-Conotoxin Reveals an Unusual and Potent Inhibitor of the Human α9α10 Nicotinic Acetylcholine Receptor.

Mar Drugs 2017 Jun 9;15(6). Epub 2017 Jun 9.

Department of Central Laboratory, Shanghai 10th People's Hospital, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China.

Conotoxins are a pool of disulfide-rich peptide neurotoxins produced by cone snails for predation and defense. They are a rich reservoir of novel ligands for ion channels, neurotransmitter receptors and transporters in the nervous system. In this study, we identified a novel conotoxin component, O-conotoxin GeXXVIIA, from the venom of . Read More

View Article and Full-Text PDF

Involvement of C-Terminal Histidines in Soybean PM1 Protein Oligomerization and Cu2+ Binding.

Plant Cell Physiol 2017 06;58(6):1018-1029

Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, PR China.

Late embryogenesis abundant (LEA) proteins are widely distributed among plant species, where they contribute to abiotic stress tolerance. LEA proteins can be classified into seven groups according to conserved sequence motifs. The PM1 protein from soybean, which belongs to the Pfam LEA_1 group, has been shown previously to be at least partially natively unfolded, to bind metal ions and potentially to stabilize proteins and membranes. Read More

View Article and Full-Text PDF