scholarly journals Structural Peptides of a Nonenveloped Virus Are Involved in Assembly and Membrane Translocation

2005 ◽  
Vol 79 (19) ◽  
pp. 12253-12263 ◽  
Author(s):  
Christophe Chevalier ◽  
Marie Galloux ◽  
Joan Pous ◽  
Céline Henry ◽  
Jérôme Denis ◽  
...  
Keyword(s):  
Virus Assembly ◽  
Three Dimensional ◽  
Cell Entry ◽  
Axis Formation ◽  
C Terminus ◽  
The Family ◽  
Bursal Disease ◽  
Control Virus ◽  
Nonenveloped Virus ◽  
Disordered Peptides

ABSTRACT The capsid of infectious bursal disease virus (IBDV), a nonenveloped virus of the family Birnaviridae, has a T=13l icosahedral shell constituted by a single protein, VP2, and several disordered peptides, all derived from the precursor pVP2. In this study, we show that two of the peptides, pep11 and pep46, control virus assembly and cell entry. Deletion of pep11 or even simple substitution of most of its residues blocks the capsid morphogenesis. Removal of pep46 also prevents capsid assembly but leads to the formation of subviral particles formed by unprocessed VP2 species. Fitting with the VP2 atomic model into three-dimensional reconstructions of these particles demonstrates that the presence of uncleaved pep46 causes a steric hindrance at the vertices, blocking fivefold axis formation. Mutagenesis of the pVP2 maturation sites confirms that C terminus processing is necessary for VP2 to acquire the correct icosahedral architecture. All peptides present on virions are accessible to proteases or biochemical labeling. One of them, pep46, is shown to induce large structural rearrangements in liposomes and to destabilize target membranes, demonstrating its implication in cell entry.

scholarly journals C Terminus of Infectious Bursal Disease Virus Major Capsid Protein VP2 Is Involved in Definition of the T Number for Capsid Assembly

2001 ◽  
Vol 75 (22) ◽  
pp. 10815-10828 ◽  
Author(s):  
José R. Castón ◽  
Jorge L. Martı́nez-Torrecuadrada ◽  
Antonio Maraver ◽  
Eleuterio Lombardo ◽  
José F. Rodrı́guez ◽  
...  
Keyword(s):  
Capsid Protein ◽  
Disease Virus ◽  
Infectious Bursal Disease Virus ◽  
Major Capsid Protein ◽  
Rna Virus ◽  
Three Dimensional ◽  
Infectious Bursal Disease ◽  
Capsid Assembly ◽  
C Terminus ◽  
Bursal Disease

ABSTRACT Infectious bursal disease virus (IBDV), a member of the Birnaviridae family, is a double-stranded RNA virus. The IBDV capsid is formed by two major structural proteins, VP2 and VP3, which assemble to form a T=13 markedly nonspherical capsid. During viral infection, VP2 is initially synthesized as a precursor, called VPX, whose C end is proteolytically processed to the mature form during capsid assembly. We have computed three-dimensional maps of IBDV capsid and virus-like particles built up by VP2 alone by using electron cryomicroscopy and image-processing techniques. The IBDV single-shelled capsid is characterized by the presence of 260 protruding trimers on the outer surface. Five classes of trimers can be distinguished according to their different local environments. When VP2 is expressed alone in insect cells, dodecahedral particles form spontaneously; these may be assembled into larger, fragile icosahedral capsids built up by 12 dodecahedral capsids. Each dodecahedral capsid is an empty T=1 shell composed of 20 trimeric clusters of VP2. Structural comparison between IBDV capsids and capsids consisting of VP2 alone allowed the determination of the major capsid protein locations and the interactions between them. Whereas VP2 forms the outer protruding trimers, VP3 is found as trimers on the inner surface and may be responsible for stabilizing functions. Since elimination of the C-terminal region of VPX is correlated with the assembly of T=1 capsids, this domain might be involved (either alone or in cooperation with VP3) in the induction of different conformations of VP2 during capsid morphogenesis.

scholarly journals The Last C-Terminal Residue of VP3, Glutamic Acid 257, Controls Capsid Assembly of Infectious Bursal Disease Virus

2004 ◽  
Vol 78 (7) ◽  
pp. 3296-3303 ◽  
Author(s):  
Christophe Chevalier ◽  
Jean Lepault ◽  
Bruno Da Costa ◽  
Bernard Delmas
Keyword(s):  
Glutamic Acid ◽  
Disease Virus ◽  
Infectious Bursal Disease Virus ◽  
Virus Assembly ◽  
Infectious Bursal Disease ◽  
Capsid Assembly ◽  
Assembly Process ◽  
Small Proteins ◽  
C Terminus ◽  
Bursal Disease

ABSTRACT Infectious bursal disease virus (IBDV) is a nonenveloped virus with an icosahedral capsid composed of two proteins, VP2 and VP3, that derive from the processing of the polyprotein NH2-pVP2-VP4-VP3-COOH. The virion contains VP1, the viral polymerase, which is both free and covalently linked to the two double-stranded RNA (dsRNA) genomic segments. In this study, the virus assembly process was studied further with the baculovirus expression system. While expression of the wild-type polyprotein was not found to be self-sufficient to give rise to virus-like particles (VLPs), deletion or replacement of the five C-terminal residues of VP3 was observed to promote capsid assembly. Indeed, the single deletion of the C-terminal glutamic acid was sufficient to induce VLP formation. Moreover, fusion of various peptides or small proteins (a green fluorescent protein or a truncated form of ovalbumin) at the C terminus of VP3 also promoted capsid assembly, suggesting that assembly required screening of the negative charges at the C terminus of VP3. The fused polypeptides mimicked the effect of VP1, which interacts with VP3 to promote VLP assembly. The C-terminal segment of VP3 was found to contain two functional domains. While the very last five residues of VP3 mainly controlled both assembly and capsid architecture, the five preceding residues constituted the VP1 (and possibly the pVP2/VP2) binding domain. Finally, we showed that capsid formation is associated with VP2 maturation, demonstrating that the protease VP4 is involved in the virus assembly process.

scholarly journals Disorder in a two-domain neuronal Ca2+-binding protein regulates domain stability and dynamics using ligand mimicry

2020 ◽  
Author(s):  
Lasse Staby ◽  
Katherine R. Kemplen ◽  
Amelie Stein ◽  
Michael Ploug ◽  
Jane Clarke ◽  
...  
Keyword(s):  
Intrinsically Disordered Proteins ◽  
Three Dimensional ◽  
Life Time ◽  
Disordered Proteins ◽  
Intrinsically Disordered ◽  
Order And Disorder ◽  
C Terminus ◽  
Close Relationship ◽  
Stability Dynamics ◽  
And Function

Abstract Understanding the interplay between sequence, structure and function of proteins has been complicated in recent years by the discovery of intrinsically disordered proteins (IDPs), which perform biological functions in the absence of a well-defined three-dimensional fold. Disordered protein sequences account for roughly 30% of the human proteome and in many proteins, disordered and ordered domains coexist. However, few studies have assessed how either feature affects the properties of the other. In this study, we examine the role of a disordered tail in the overall properties of the two-domain, calcium-sensing protein neuronal calcium sensor 1 (NCS-1). We show that loss of just six of the 190 residues at the flexible C-terminus is sufficient to severely affect stability, dynamics, and folding behavior of both ordered domains. We identify specific hydrophobic contacts mediated by the disordered tail that may be responsible for stabilizing the distal N-terminal domain. Moreover, sequence analyses indicate the presence of an LSL-motif in the tail that acts as a mimic of native ligands critical to the observed order–disorder communication. Removing the disordered tail leads to a shorter life-time of the ligand-bound complex likely originating from the observed destabilization. This close relationship between order and disorder may have important implications for how investigations into mixed systems are designed and opens up a novel avenue of drug targeting exploiting this type of behavior.

Prenatal Diagnosis

1992 ◽  
Vol 13 (9) ◽  
pp. 334-342
Author(s):  
John H. DiLiberti ◽  
Mark A. Greenstein ◽  
Sally Shulman Rosengren
Keyword(s):  
Prenatal Diagnosis ◽  
Imaging Techniques ◽  
Three Dimensional ◽  
Prenatal Testing ◽  
The Past ◽  
Computerized Image Processing ◽  
The Family ◽  
Family History Assessment ◽  
Additional Explanation ◽  
Pediatric Disorders

The enormous progress witnessed in the field of prenatal diagnosis during the past two decades is likely to continue into the future. Improved imaging techniques are likely to enhance the resolution of noninvasively obtained fetal images considerably over their current excellent quality. Although this undoubtedly will be true for ultrasonography, the increased speed of magnetic resonance equipment may offer a new realm of imaging possibilities. Computerized image processing, analysis, and three-dimensional reconstructions all should make interpretation of fetal images easier and more understandable to the nonspecialist. Advances in molecular genetics will continue to accelerate, greatly expanding the range and accuracy of prenatal diagnosis. The alert pediatrician who is sensitive to genetic issues may, by early detection of pediatric disorders and careful family history assessment, be in a position to identify families at risk for serious genetic conditions and provide the opportunity to make informed decisions on reproductive options that avert a major tragedy. The pediatrician, working with obstetric colleagues, should be part of a team effort to support families going through prenatal testing. Familiarity with these rapidly changing technologies will make it far easier to support the family needing additional explanation about prenatal diagnosis issues.

scholarly journals Improved scFv Anti-LOX-1 Binding Activity by Fusion with LOX-1-Binding Peptides

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Wei Hu ◽  
Qiuhong Xie ◽  
Hongyu Xiang
Keyword(s):  
Targeted Delivery ◽  
Structural Characteristics ◽  
Low Density Lipoprotein ◽  
Three Dimensional ◽  
Density Lipoprotein ◽  
Binding Activity ◽  
Single Chain ◽  
C Terminus ◽  
Density Lipoprotein Receptor ◽  
Therapeutic Molecules

The oxidized low-density lipoprotein receptor-1 (LOX-1) targeted single-chain variable fragment (scFvs) is a promising molecule for the targeted delivery of imaging and therapeutic molecules of atherosclerotic diseases; however, its applications are limited by the inherent low antigen affinity. In this study, the three-dimensional (3D) model of the anti-LOX-1 scFv was constructed and its docking with the LOX-1 protein was developed. To improve the LOX-1-binding activity, the anti-LOX-1 scFv was designed to fuse with one of three LOX-1-binding heptapeptides, LTPATAI, FQTPPQL, and LSIPPKA, at its N-terminus and C-terminus and in the linker region, which have different LOX-1-binding interfaces with the anti-LOX-1 scFv analyzed by an array of computational approaches. These scFv/peptide fusions were constructed, successfully expressed in Brevibacillus choshinensis hosts, and purified by a two-step column purification process. The antigen binding activity, structural characteristics, thermal stability, and stability in serum of these fusion proteins were examined. Results showed that the scFv with N-terminal fusing peptides proteins demonstrated increased LOX-1-binding activity without decrease in stability. These findings will help increase the application efficacy of LOX-1 targeting scFv in LOX-1-based therapy.

LIMITING DYNAMICS FOR THE COMPLEX STANDARD FAMILY

1995 ◽  
Vol 05 (03) ◽  
pp. 673-699 ◽  
Author(s):  
NÚRIA FAGELLA
Keyword(s):  
Cross Sections ◽  
Julia Set ◽  
Three Dimensional ◽  
Mandelbrot Set ◽  
Dimensional Parameter ◽  
Quadratic Polynomials ◽  
New Family ◽  
Standard Family ◽  
The Family ◽  
Characteristic Features

The complexification of the standard family of circle maps Fαβ(θ)=θ+α+β+β sin(θ) mod (2π) is given by Fαβ(ω)=ωeiαe(β/2)(ω−1/ω) and its lift fαβ(z)=z+a+β sin(z). We investigate the three-dimensional parameter space for Fαβ that results from considering a complex and β real. In particular, we study the two-dimensional cross-sections β=constant as β tends to zero. As the functions tend to the rigid rotation Fα,0, their dynamics tend to the dynamics of the family Gλ(z)=λzez where λ=e−iα. This new family exhibits behavior typical of the exponential family together with characteristic features of quadratic polynomials. For example, we show that the λ-plane contains infinitely many curves for which the Julia set of the corresponding maps is the whole plane. We also prove the existence of infinitely many sets of λ values homeomorphic to the Mandelbrot set.

scholarly journals Palynological analysis of Dennstaedtiaceae taxa from the Paranaense Phytogeographic Province that produce Trilete spores II: Microlepia speluncae and Pteridium arachnoideum

2016 ◽  
Vol 88 (2) ◽  
pp. 877-890 ◽  
Author(s):  
Agustina Yañez ◽  
Gonzalo J. Marquez ◽  
Marta A. Morbelli
Keyword(s):  
Comparative Analysis ◽  
Three Dimensional ◽  
Middle Layer ◽  
The Other ◽  
Spore Morphology ◽  
Central Channel ◽  
Palynological Analysis ◽  
Dimensional Network ◽  
The Family ◽  
Wall Ultrastructure

The spore morphology and wall ultrastructure of Microlepia speluncae and Pteridium arachnoideum from the Paranaense Province were analyzed with LM, SEM and TEM and a comparative analysis was carried out. In both species the spores are covered by a three-dimensional network of threads branched and fused, tangentially arranged to the surface, and some free-end threads are also seen. The species were differentiated by morphology and the frequency of threads fusion and the networks distribution on the surface of the spores. In both species the exospore is two-layered in section, both layers are traversed by single or branched channels. The perispore is three-layered in section: the inner layer is adhered to the exospore, the middle layer is formed of a three-dimensional network of threads and the outer layer is discontinuous. The perispore ultrastructure of Microlepia speluncae was interpreted as formed of helical subunits displayed around a central channel. The spore morphology and perispore ultrastructure allow differentiating Microlepia from Pteridium but also to the other Dennstaedtiaceae genera that grow in the Paranaense Province. The results obtained allow establishing relationships that let us recognize different groups and gave a new reference to get a better knowledge of the family.

The 3D IFB SWOT Analysis as a Strategic Tool to Develop Entrepreneurial Plans for Family Businesses

2020 ◽  
pp. 363-389
Author(s):  
Luz Leyda Vega-Rosado
Keyword(s):  
Family Business ◽  
Swot Analysis ◽  
Three Dimensional ◽  
Family Firm ◽  
Second Phase ◽  
The Third ◽  
Third Phase ◽  
The Family ◽  
Generational Groups ◽  
The Individual

This chapter provides a framework that family business members can use to strategically and entrepreneurially evaluate themselves before they prepare the final strategic plan of the family firm. The tool consists of four phases. The first phase is the Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis of the Individuals that are members of the family business. The second phase is the SWOT analysis of the Family's generational groups. Each generation in the family business will work in groups according to their year of birth. The third phase is the SWOT analysis of the Business. The fourth and most important phase is the integration called 3D IFB SWOT Analysis. It is 3D because it is three-dimensional, integrating the Individual, the Family's generations, and the Business.

scholarly journals Naturally Prefabricated Marine Biomaterials: Isolation and Applications of Flat Chitinous 3D Scaffolds from Ianthella labyrinthus (Demospongiae: Verongiida)

2019 ◽  
Vol 20 (20) ◽  
pp. 5105 ◽  
Author(s):  
Mario Schubert ◽  
Björn Binnewerg ◽  
Alona Voronkina ◽  
Lyubov Muzychka ◽  
Marcin Wysokowski ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Three Dimensional ◽  
Marine Sponges ◽  
Biologically Active ◽  
3D Scaffolds ◽  
Chemical Treatments ◽  
The Family ◽  
Unique Source ◽  
Induced Pluripotent ◽  
First Time

Marine sponges remain representative of a unique source of renewable biological materials. The demosponges of the family Ianthellidae possess chitin-based skeletons with high biomimetic potential. These three-dimensional (3D) constructs can potentially be used in tissue engineering and regenerative medicine. In this study, we focus our attention, for the first time, on the marine sponge Ianthella labyrinthus Bergquist & Kelly-Borges, 1995 (Demospongiae: Verongida: Ianthellidae) as a novel potential source of naturally prestructured bandage-like 3D scaffolds which can be isolated simultaneously with biologically active bromotyrosines. Specifically, translucent and elastic flat chitinous scaffolds have been obtained after bromotyrosine extraction and chemical treatments of the sponge skeleton with alternate alkaline and acidic solutions. For the first time, cardiomyocytes differentiated from human induced pluripotent stem cells (iPSC-CMs) have been used to test the suitability of I. labyrinthus chitinous skeleton as ready-to-use scaffold for their cell culture. Results reveal a comparable attachment and growth on isolated chitin-skeleton, compared to scaffolds coated with extracellular matrix mimetic Geltrex®. Thus, the natural, unmodified I. labyrinthus cleaned sponge skeleton can be used to culture iPSC-CMs and 3D tissue engineering. In addition, I. labyrinthus chitin-based scaffolds demonstrate strong and efficient capability to absorb blood deep into the microtubes due to their excellent capillary effect. These findings are suggestive of the future development of new sponge chitin-based absorbable hemostats as alternatives to already well recognized cellulose-based fabrics.

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