Spin symmetry transitions make DNA strands separate. New insight into the mechanism of transcription.

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

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

更新日期：2009-07-01 00:00:00

abstract：:Tumor metastasis involves a progressive loss of tissue architecture and dissolution of structural boundaries between the epithelium and connective tissue. The basement membrane (BM), a specialized network of extracellular matrix proteins forms a barrier that physically restricts pre-invasive lesions such that they rem...

journal_title：Physical biology

authors： Tanner K

更新日期：2012-12-01 00:00:00

abstract：:A central question in eukaryotic cell biology asks, during cell division, how is the growth and distribution of organelles regulated to ensure each daughter cell receives an appropriate amount. For vacuoles in budding yeast, there are well described organelle-to-cell size scaling trends as well as inheritance mechanis...

journal_title：Physical biology

authors： Chadwick WL,Biswas SK,Bianco S,Chan YM

更新日期：2020-10-09 00:00:00

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

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

更新日期：2013-04-01 00:00:00

abstract：:A vast literature has explored the genetic interactions among the cellular components regulating gene expression in many organisms. Early on, in the absence of any biochemical definition, regulatory modules were conceived using the strict formalism of genetics to designate the modifiers of phenotype as either cis- or ...

journal_title：Physical biology

authors： Levens D,Benham CJ

更新日期：2011-06-01 00:00:00

abstract：:Epithelial-to-mesenchymal transition (EMT) is a fundamental developmental process wherein polarized epithelial cells lose their junctional architecture and apical-basal polarity to become motile mesenchymal cells, and there is emerging evidence for its role in propagating tumor dissemination. While many multifaceted n...

journal_title：Physical biology

authors： Antony J,Thiery JP,Huang RY

更新日期：2019-05-07 00:00:00

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

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

更新日期：2013-06-01 00:00:00

abstract：:The intrinsic stochasticity of gene expression can lead to large variability in protein levels for genetically identical cells. Such variability in protein levels can arise from infrequent synthesis of mRNAs which in turn give rise to bursts of protein expression. Protein expression occurring in bursts has indeed been...

journal_title：Physical biology

authors： Elgart V,Jia T,Fenley AT,Kulkarni R

更新日期：2011-08-01 00:00:00

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

authors： Félix MA

更新日期：2012-08-01 00:00:00

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

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

更新日期：2015-05-28 00:00:00

abstract：:Particle tracking offers significant insight into the molecular mechanics that govern the behavior of living cells. The analysis of molecular trajectories that transition between different motive states, such as diffusive, driven and tethered modes, is of considerable importance, with even single trajectories containi...

journal_title：Physical biology

authors： Young DC,Scrimgeour J

更新日期：2018-07-06 00:00:00

abstract：:Bacteria such as Escherichia coli propel themselves by rotating a bundle of helical filaments, each driven by a rotary motor embedded in the cell membrane. Each filament is an assembly of thousands of copies of the protein flagellin which assumes two different states. We model the filament by an elastic network of rig...

journal_title：Physical biology

authors： Speier C,Vogel R,Stark H

更新日期：2011-08-01 00:00:00

abstract：:Increasing numbers of physicists engage in research activities that address biological questions from physics perspectives or strive to develop physics insights from active biological processes. The on-going development and success of such activities morph our ways of thinking about what it is to 'do biophysics' and a...

journal_title：Physical biology

authors： Hoogenboom BW,Leake MC

更新日期：2018-07-06 00:00:00

abstract：:Neurofilaments are transported along axons stochastically in a stop-and-go manner, cycling between brief bouts of rapid movement and pauses that can vary from seconds to hours in length. Presently the only way to analyze neurofilament pausing experimentally on both long and short time scales is the pulse-escape method...

journal_title：Physical biology

authors： Li Y,Brown A,Jung P

更新日期：2014-04-01 00:00:00

abstract：:In this article the notion of metabolic turnover is revisited in the light of recent results of out-of-equilibrium thermodynamics. By means of Monte Carlo methods we perform an exact sampling of the enzymatic fluxes in a genome scale metabolic network of E. coli in stationary growth conditions from which we infer the ...

journal_title：Physical biology

authors： De Martino D

更新日期：2016-01-29 00:00:00

abstract：:Successful biological development via spatial regulation of cell differentiation relies on the action of multiple signaling molecules that are known as morphogens. It is now well-established that signaling molecules create non-uniform concentration profiles, morphogen gradients, that activate different genes, leading ...

journal_title：Physical biology

authors： Teimouri H,Kolomeisky AB

更新日期：2015-04-17 00:00:00

abstract：:The controlling factors that underlie the growth of tumors have often been hard to identify because of the presence in this system of a large number of intracellular biochemical parameters. Here, we propose a simplifying framework to identify the key physical parameters that govern the early growth of tumors. We model...

journal_title：Physical biology

authors： Remy G,Cluzel P

更新日期：2016-04-04 00:00:00

abstract：:The glycolytic enzyme pyruvate kinase M2 (PKM2) exists in both catalytically inactive dimeric and active tetrameric forms. In cancer cells, PKM2 dimer predominance contributes to tumor growth by triggering glycolytic reprogramming. However, the mechanism that promotes PKM2 dimer predominance over tetramer in cancer ce...

journal_title：Physical biology

authors： Shi X,You L,Luo RY

更新日期：2019-09-18 00:00:00

abstract：:Thrombosis accounts for 80% of deaths in patients with diabetes mellitus. Diabetic patients demonstrate tortuous microvessels and larger than normal platelets. Large platelets are associated with increased platelet activation and thrombosis, but the physical effects of large platelets in the microscale processes of th...

journal_title：Physical biology

authors： Chesnutt JK,Han HC

更新日期：2013-10-01 00:00:00

abstract：:Surface plasmon resonance (SPR) chips are widely used to measure association and dissociation rates for the binding kinetics between two species of chemicals, e.g., cell receptors and ligands. It is commonly assumed that ligands are spatially well mixed in the SPR region, and hence a mean-field rate equation descripti...

journal_title：Physical biology

authors： Carroll J,Raum M,Forsten-Williams K,Täuber UC

更新日期：2016-12-06 00:00:00

abstract：:How do the cells in our body reconfigure their shape to achieve complex tasks like migration and mitosis, yet maintain their shape in response to forces exerted by, for instance, blood flow and muscle action? Cell shape control is defined by a delicate mechanical balance between active force generation and passive mat...

journal_title：Physical biology

authors： Mulla Y,Aufderhorst-Roberts A,Koenderink GH

更新日期：2018-04-30 00:00:00

abstract：:Motile biological cells in tissue often display the phenomenon of durotaxis, i.e. they tend to move towards stiffer parts of substrate tissue. The mechanism for this behavior is not completely understood. We consider simplified models for durotaxis based on the classic persistent random walker scheme. We show that eve...

journal_title：Physical biology

authors： Doering CR,Mao X,Sander LM

更新日期：2018-09-11 00:00:00

abstract：:Based on recent experimental data, we design a model for neuronal membrane potentials that incorporates the influence of the surrounding glia (dressed neurons). A neurotransmitter released into the synaptic cleft triggers a Ca(2+) response in nearby glial cells that spreads as a Ca(2+) wave and interacts with other sy...

journal_title：Physical biology

authors： Nadkarni S,Jung P

更新日期：2004-06-01 00:00:00

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

authors： Spedden E,Kaplan DL,Staii C

更新日期：2013-10-01 00:00:00

abstract：:Epigenetic mechanisms of silencing via heritable chromatin modifications play a major role in gene regulation and cell fate specification. We consider a model of epigenetic chromatin silencing in budding yeast and study the bifurcation diagram and characterize the bistable and the monostable regimes. The main focus of...

journal_title：Physical biology

authors： Dayarian A,Sengupta AM

更新日期：2013-06-01 00:00:00

abstract：:Self-organization processes in multicellular aggregates of bacteria and amoebae offer fascinating insights into the evolution of cooperation and differentiation of cells. During myxobacterial development a variety of spatio-temporal patterns emerges such as counterpropagating waves of cell density that are known as ri...

journal_title：Physical biology

authors： Börner U,Deutsch A,Bär M

更新日期：2006-06-23 00:00:00

abstract：:Staphylococcus aureus is an important pathogen, giving rise to antimicrobial resistance in cell strains such as Methicillin Resistant S. aureus (MRSA). Here we report an image analysis framework for automated detection and image segmentation of cells in S. aureus cell clusters, and explicit identification of their cel...

journal_title：Physical biology

authors： Wollman AJ,Miller H,Foster S,Leake MC

更新日期：2016-10-17 00:00:00

abstract：:Sequence-dependent DNA flexibility is an important structural property originating from the DNA 3D structure. In this paper, we investigate the DNA flexibility of the budding yeast (S. Cerevisiae) replication origins on a genome-wide scale using flexibility parameters from two different models, the trinucleotide and t...

journal_title：Physical biology

authors： Cao XQ,Zeng J,Yan H

更新日期：2008-09-29 00:00:00

abstract：:When the author arrived in Berkeley, in the mid 1970s, to study Biophysics he soon felt as if he was engaging himself in a somewhat marginal activity. Biology was then entering another of its cyclical periods of annotation that was to culminate with the human genome project. Two decades later, however, at the end of t...

journal_title：Physical biology

authors： Bustamante CJ

更新日期：2014-10-08 00:00:00

abstract：:The translocation of molecules across cellular membranes or through synthetic nanopores is strongly affected by thermal fluctuations. In this work we study how the dynamics of a polymer in a noisy environment changes when the translocation process is driven by an oscillating electric field. An improved version of the ...

journal_title：Physical biology

authors： Pizzolato N,Fiasconaro A,Adorno DP,Spagnolo B

更新日期：2010-08-04 00:00:00