The size of knots in polymers.

Abstract:

:Circular DNA in viruses and bacteria is often knotted. While mathematically problematic, the determination of the knot size is crucial for the study of the physical and biological behaviour of long macromolecules. Here, we review work on the size distribution of these knots under equilibrium conditions. We discuss knot localization in good and poor solvents, or in polymers that are adsorbed on a surface. We also discuss recent evidence that knot size is a crucial quantity in relaxation processes of knotted polymers.

journal_name

Phys Biol

journal_title

Physical biology

authors

Orlandini E,Stella AL,Vanderzande C

doi

10.1088/1478-3975/6/2/025012

subject

Has Abstract

pub_date

2009-07-01 00:00:00

pages

025012

issue

2

eissn

1478-3967

issn

1478-3975

pii

S1478-3975(09)96067-8

journal_volume

6

pub_type

杂志文章
  • Multi-scale modelling of cancer cell intravasation: the role of cadherins in metastasis.

    abstract::Transendothelial migration is a crucial process of the metastatic cascade in which a malignant cell attaches itself to the endothelial layer forming the inner wall of a blood or lymph vessel and creates a gap through which it enters into the bloodstream (or lymphatic system) and then is transported to distant parts of...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/6/1/016008

    authors: Ramis-Conde I,Chaplain MA,Anderson AR,Drasdo D

    更新日期:2009-03-25 00:00:00

  • Stretching and unfolding of multidomain biopolymers: a statistical mechanics theory of titin.

    abstract::Single-molecule manipulation has allowed the forced unfolding of multidomain proteins. Here we develop a theory that not only explains these experiments, but also points out a number of difficulties in their interpretation and makes suggestions for further experiments. Our theory is valid for essentially any molecule ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/6/2/025005

    authors: Staple DB,Payne SH,Reddin AL,Kreuzer HJ

    更新日期:2009-07-01 00:00:00

  • The linear noise approximation for molecular fluctuations within cells.

    abstract::We study the applicability of Van Kampen's linear noise approximation to the calculation of fluctuations in cells due to small number of molecules for simple genetic systems not previously considered. These systems include dimer formation and feedback. We explain why the linear noise approximation can be surprisingly ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3967/1/4/002

    authors: Hayot F,Jayaprakash C

    更新日期:2004-12-01 00:00:00

  • Caenorhabditis elegans vulval cell fate patterning.

    abstract::The spatial patterning of three cell fates in a row of competent cells is exemplified by vulva development in the nematode Caenorhabditis elegans. The intercellular signaling network that underlies fate specification is well understood, yet quantitative aspects remain to be elucidated. Quantitative models of the netwo...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/9/4/045001

    authors: Félix MA

    更新日期:2012-08-01 00:00:00

  • A large number of receptors may reduce cellular response time variation.

    abstract::Cells often have tens of thousands of receptors, even though only a few activated receptors can trigger full cellular responses. Reasons for the overabundance of receptors remain unclear. We suggest that, under certain conditions, the large number of receptors can result in a competition among receptors to be the firs...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/3/035008

    authors: Cheng X,Merchan L,Tchernookov M,Nemenman I

    更新日期:2013-06-01 00:00:00

  • Multiscale model for the effects of adaptive immunity suppression on the viral therapy of cancer.

    abstract::Oncolytic virotherapy-the use of viruses that specifically kill tumor cells-is an innovative and highly promising route for treating cancer. However, its therapeutic outcomes are mainly impaired by the host immune response to the viral infection. In this paper, we propose a multiscale mathematical model to study how t...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/2/025005

    authors: Paiva LR,Silva HS,Ferreira SC,Martins ML

    更新日期:2013-04-01 00:00:00

  • Temperature response of the neuronal cytoskeleton mapped via atomic force and fluorescence microscopy.

    abstract::Neuronal cells change their growth properties in response to external physical stimuli such as variations in external temperature, stiffness of the growth substrate, or topographical guidance cues. Detailed knowledge of the mechanisms that control these biomechanical responses is necessary for understanding the basic ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/5/056002

    authors: Spedden E,Kaplan DL,Staii C

    更新日期:2013-10-01 00:00:00

  • The role of IDH1 mutated tumour cells in secondary glioblastomas: an evolutionary game theoretical view.

    abstract::Recent advances in clinical medicine have elucidated two significantly different subtypes of glioblastoma which carry very different prognoses, both defined by mutations in isocitrate dehydrogenase-1 (IDH-1). The mechanistic consequences of this mutation have not yet been fully clarified, with conflicting opinions exi...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/8/1/015016

    authors: Basanta D,Scott JG,Rockne R,Swanson KR,Anderson AR

    更新日期:2011-02-01 00:00:00

  • Phosphatase localization in bacterial chemotaxis: divergent mechanisms, convergent principles.

    abstract::Chemotaxis is the process by which cells sense changes in their chemical environment and move towards more favorable conditions. In divergent species of bacteria, the chemotaxis proteins localize to the poles of the cell and information is transferred to the flagellar motors through the phosphorylation of a soluble pr...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/2/3/002

    authors: Rao CV,Kirby JR,Arkin AP

    更新日期:2005-07-14 00:00:00

  • Modeling capsid self-assembly: design and analysis.

    abstract::A series of simulations aimed at elucidating the self-assembly dynamics of spherical virus capsids is described. This little-understood phenomenon is a fascinating example of the complex processes that occur in the simplest of organisms. The fact that different viruses adopt similar structural forms is an indication o...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/7/4/045001

    authors: Rapaport DC

    更新日期:2010-12-09 00:00:00

  • Uncovering the release mechanism of nucleotide import by HIV-1 capsid.

    abstract::Efficient nucleotide import is critical to fuel the reverse DNA synthesis that takes place within the HIV-1 capsid. However, the mechanism by which the HIV-1 capsid imports nucleotides is presently unclear. In this work, we carry out a series of Brownian diffusion simulations to elucidate the nucleotide import process...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/abbf32

    authors: Song G

    更新日期:2020-10-07 00:00:00

  • The effect of composition on diffusion of macromolecules in a crowded environment.

    abstract::We study diffusion of macromolecules in a crowded cytoplasm-like environment, focusing on its dependence on composition and its crossover to the anomalous subdiffusion. The crossover and the diffusion itself depend on both the volume fraction and the relative concentration of macromolecules. In accordance with previou...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/12/4/046003

    authors: Kondrat S,Zimmermann O,Wiechert W,von Lieres E

    更新日期:2015-05-28 00:00:00

  • Thermostability in rubredoxin and its relationship to mechanical rigidity.

    abstract::The source of increased stability in proteins from organisms that thrive in extreme thermal environments is not well understood. Previous experimental and theoretical studies have suggested many different features possibly responsible for such thermostability. Many of these thermostabilizing mechanisms can be accounte...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/7/1/016002

    authors: Rader AJ

    更新日期:2009-12-11 00:00:00

  • The role of carrier number on the procoagulant activity of tissue factor in blood and plasma.

    abstract::Tissue factor (TF) is a transmembrane glycoprotein cofactor of activated blood coagulation factor VII (FVIIa) that is required for hemostatic thrombin generation at sites of blood vessel injury. Membrane-associated TF detected in circulating blood of healthy subjects, referred to as intravascular or circulating TF has...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/8/6/066005

    authors: Tormoen GW,Rugonyi S,Gruber A,McCarty OJ

    更新日期:2011-12-01 00:00:00

  • Environmental selection of the feed-forward loop circuit in gene-regulation networks.

    abstract::Gene-regulation networks contain recurring elementary circuits termed network motifs. It is of interest to understand under which environmental conditions each motif might be selected. To address this, we study one of the most significant network motifs, a three-gene circuit called the coherent feed-forward loop (FFL)...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/2/2/001

    authors: Dekel E,Mangan S,Alon U

    更新日期:2005-06-01 00:00:00

  • Effect of palytoxin on the sodium-potassium pump: model and simulation.

    abstract::We propose a reaction model for the palytoxin-sodium-potassium (PTX-Na(+)/K(+)) pump complex. The model, which is similar to the Albers-Post model for Na(+)/K(+)-ATPase, is used to elucidate the effect of PTX on Na(+)/K(+)-ATPase during the enzyme interactions with Na(+) and/or K(+) ions. Conformational substates and ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/5/3/036005

    authors: Rodrigues AM,Almeida AC,Infantosi AF

    更新日期:2008-07-29 00:00:00

  • The role of the bi-compartmental stem cell niche in delaying cancer.

    abstract::In recent years, by using modern imaging techniques, scientists have found evidence of collaboration between different types of stem cells (SCs), and proposed a bi-compartmental organization of the SC niche. Here we create a class of stochastic models to simulate the dynamics of such a heterogeneous SC niche. We consi...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/12/5/055001

    authors: Shahriyari L,Komarova NL

    更新日期:2015-07-31 00:00:00

  • FtsZ rings and helices: physical mechanisms for the dynamic alignment of biopolymers in rod-shaped bacteria.

    abstract::In many bacterial species, the protein FtsZ forms a cytoskeletal ring that marks the future division site and scaffolds the division machinery. In rod-shaped bacteria, most frequently membrane-attached FtsZ rings or ring fragments are reported and occasionally helices. By contrast, axial FtsZ clusters have never been ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/9/1/016009

    authors: Fischer-Friedrich E,Friedrich BM,Gov NS

    更新日期:2012-02-01 00:00:00

  • Follow-the-leader cell migration requires biased cell-cell contact and local microenvironmental signals.

    abstract::Directed cell migration often involves at least two types of cell motility that include multicellular streaming and chain migration. However, what is unclear is how cell contact dynamics and the distinct microenvironments through which cells travel influence the selection of one migratory mode or the other. The embryo...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/3/035003

    authors: Wynn ML,Rupp P,Trainor PA,Schnell S,Kulesa PM

    更新日期:2013-06-01 00:00:00

  • Topographical and mechanical characterization of living eukaryotic cells on opaque substrates: development of a general procedure and its application to the study of non-adherent lymphocytes.

    abstract::The mechanical behavior of living murine T-lymphocytes was assessed by atomic force microscopy (AFM). A robust experimental procedure was developed to overcome some features of lymphocytes, in particular their spherical shape and non-adherent character. The procedure included the immobilization of the lymphocytes on a...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/12/2/026005

    authors: Daza R,Cruces J,Arroyo-Hernández M,Marí-Buyé N,De la Fuente M,Plaza GR,Elices M,Pérez-Rigueiro J,Guinea GV

    更新日期:2015-03-19 00:00:00

  • On the origin of the tensile strength of insect swarms.

    abstract::Traditionally animal groups have been characterized by the macroscopic patterns that they form. It is now recognised that such patterns convey limited information about the nature of the aggregation as a whole. Aggregate properties cannot be determined by passive observations alone; instead one must interact with them...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/ab12b9

    authors: Reynolds AM

    更新日期:2019-04-23 00:00:00

  • Modeling proteasome dynamics in Parkinson's disease.

    abstract::In Parkinson's disease (PD), there is evidence that alpha-synuclein (alphaSN) aggregation is coupled to dysfunctional or overburdened protein quality control systems, in particular the ubiquitin-proteasome system. Here, we develop a simple dynamical model for the on-going conflict between alphaSN aggregation and the m...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/6/3/036005

    authors: Sneppen K,Lizana L,Jensen MH,Pigolotti S,Otzen D

    更新日期:2009-05-01 00:00:00

  • Effect of co-transporter blockers on non-synaptic epileptiform activity-computational simulation.

    abstract::The important role of cation-chloride co-transporters in epilepsy is being supported by an increasing number of investigations. However, enormous complexity is involved since the action of these co-transporters has effects on the ionic homeostasis influencing directly the neuronal excitability and the tissue propensit...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/5/056008

    authors: Lopes MR,Santos LE,Rodrigues AM,Duarte MA,Infantosi AF,Scorza FA,Arida RM,Madureira AP,da Silveira GA,dos Santos IC,Cavalheiro EA,de Almeida AC

    更新日期:2013-10-01 00:00:00

  • Current trends and future requirements for the mass spectrometric investigation of microbial, mammalian and plant metabolomes.

    abstract::The functional levels of biological cells or organisms can be separated into the genome, transcriptome, proteome and metabolome. Of these the metabolome offers specific advantages to the investigation of the phenotype of biological systems. The investigation of the metabolome (metabolomics) has only recently appeared ...

    journal_title:Physical biology

    pub_type: 杂志文章,评审

    doi:10.1088/1478-3975/5/1/011001

    authors: Dunn WB

    更新日期:2008-02-20 00:00:00

  • Control of ribosome traffic by position-dependent choice of synonymous codons.

    abstract::Messenger RNA (mRNA) encodes a sequence of amino acids by using codons. For most amino acids, there are multiple synonymous codons that can encode the amino acid. The translation speed can vary from one codon to another, thus there is room for changing the ribosome speed while keeping the amino acid sequence and hence...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/10/5/056011

    authors: Mitarai N,Pedersen S

    更新日期:2013-10-01 00:00:00

  • Modeling synaptic transmission of the tripartite synapse.

    abstract::The tripartite synapse denotes the junction of a pre- and postsynaptic neuron modulated by a synaptic astrocyte. Enhanced transmission probability and frequency of the postsynaptic current-events are among the significant effects of the astrocyte on the synapse as experimentally characterized by several groups. In thi...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/4/1/001

    authors: Nadkarni S,Jung P

    更新日期:2007-01-09 00:00:00

  • Replicating landmine blast loading in cellular in vitro models.

    abstract::Trauma arising from landmines and improvised explosive devices promotes heterotopic ossification, the formation of extra-skeletal bone in non-osseous tissue. To date, experimental platforms that can replicate the loading parameter space relevant to improvised explosive device and landmine blast wave exposure have not ...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/ab7d1c

    authors: Sory DR,Amin HD,Chapman DJ,Proud WG,Rankin SM

    更新日期:2020-08-12 00:00:00

  • Roadmap on multiscale coupling of biochemical and mechanical signals during development.

    abstract::How interactions between mechanics and biochemistry lead to the emergence of complex cell and tissue organization is an old question that has recently attracted renewed interest from biologists, physicists, mathematicians and computer scientists. Rapid advances in optical physics, microscopy and computational image an...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/abd0db

    authors: Lenne PF,Munro E,Heemskerk I,Warmflash A,Bocanegra-Moreno L,Kishi K,Kicheva A,Long Y,Fruleux A,Boudaoud A,Saunders TE,Caldarelli P,Michaut A,Gros J,Maroudas-Sacks Y,Keren K,Hannezo E,Gartner ZJ,Stormo BS,Gladfelter

    更新日期:2020-12-04 00:00:00

  • Mechanical properties of branched actin filaments.

    abstract::Cells moving on a two dimensional substrate generate motion by polymerizing actin filament networks inside a flat membrane protrusion. New filaments are generated by branching off existing ones, giving rise to branched network structures. We investigate the force-extension relation of branched filaments, grafted on an...

    journal_title:Physical biology

    pub_type: 杂志文章

    doi:10.1088/1478-3975/12/4/046007

    authors: Razbin M,Falcke M,Benetatos P,Zippelius A

    更新日期:2015-06-04 00:00:00

  • The diversity of physical forces and mechanisms in intermolecular interactions.

    abstract::Intermolecular interactions became an inherent part of the structure-function paradigm. Therefore, the generalized concept of protein stability and interactions should consider the balance of stabilizing forces working in different types of intermolecular interactions. We consider here two 'extremes' of protein intera...

    journal_title:Physical biology

    pub_type: 杂志文章,评审

    doi:10.1088/1478-3975/8/3/035002

    authors: Berezovsky IN

    更新日期:2011-06-01 00:00:00