Membrane potentials, oxidative stress and the dispersal response of bacterial biofilms to 405 nm light.

abstract：:Cells respond to the environment by regulating the expression of genes according to environmental signals. The relation between the input signal level and the expression of the gene is called the gene regulation function. It is of interest to understand the shape of a gene regulation function in terms of the environme...

journal_title：Physical biology

authors： Kalisky T,Dekel E,Alon U

更新日期：2007-11-07 00:00:00

abstract：:Bistable regulatory elements enhance heterogeneity in cell populations and, in multicellular organisms, allow cells to specialize and specify their fate. Our study demonstrates that in a system of bistable genetic switch, the noise characteristics control in which of the two epigenetic attractors the cell population w...

journal_title：Physical biology

authors： Jaruszewicz J,Lipniacki T

更新日期：2013-06-01 00:00:00

abstract：:In addition to serving as structural elements and as tracks for motor proteins, microtubules use chemical energy derived from the hydrolysis of GTP to generate forces when growing and shrinking. These forces are used to push or pull on organelles such as chromosomes and the mitotic spindle. If an array of microtubules...

journal_title：Physical biology

authors： Howard J

更新日期：2006-02-28 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：:A DNA triplex is formed through binding of a third strand to the major groove of a duplex. Due to the high charge density of a DNA triplex, metal ions are critical for its stability. We recently developed the tightly bound ion (TBI) model for ion-nucleic acids interactions. The model accounts for the potential correla...

journal_title：Physical biology

authors： Chen G,Chen SJ

更新日期：2011-12-01 00:00:00

abstract：:Gravity or ultracentrifuge settling of colloidal particles and macromolecules usually involves several disperse species, either because natural and industrial colloids display a large size polydispersity, or because additives are put in on purpose to allow for density-based fractionation of the suspension. Such 'macro...

journal_title：Physical biology

authors： Piazza R,Buzzaccaro S,Secchi E,Parola A

更新日期：2013-08-01 00:00:00

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

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

更新日期：2009-05-01 00:00:00

abstract：:A cluster of neural crest cells (NCCs) may chemotax up a shallow external gradient to which a single cell is unresponsive. To explain this intriguing 'group advantage', we propose a chemo-mechanical model based on the signaling proteins Rac1 and RhoA. We represent each cell as a polygon with nodes connected by elastic...

journal_title：Physical biology

authors： Merchant B,Feng JJ

更新日期：2020-03-10 00:00:00

abstract：:The study on aerial plant organs (leaves and stems) motions is reviewed. The history of observations and studies is put in the perspective of the ideas surrounding them, leading to a presentation of the current classification of these motions. After showing the shortcomings of such a classification, we present, follow...

journal_title：Physical biology

authors： Rivière M,Derr J,Douady S

更新日期：2017-08-21 00:00:00

abstract：:A two-dimensional model is proposed for intercellular calcium (Ca(2 +)) waves with Ca(2 +)-induced IP(3) regeneration and the diffusion of IP(3) through gap junctions. Many experimental observations in glial cells, i.e. responding to local mechanical stimulation, glutamate application, mechanical stimulation followed ...

journal_title：Physical biology

authors： Wei F,Shuai J

更新日期：2011-04-01 00:00:00

abstract：:Many single-cell observables are highly heterogeneous. A part of this heterogeneity stems from age-related phenomena: the fact that there is a nonuniform distribution of cells with different ages. This has led to a renewed interest in analytic methodologies including use of the 'von Foerster equation' for predicting p...

journal_title：Physical biology

authors： Rochman ND,Popescu DM,Sun SX

更新日期：2018-03-14 00:00:00

abstract：:Monolayer expansion has generated great interest as a model system to study collective cell migration. During such an expansion the culture front often develops 'fingers', which we have recently modeled using a proposed feedback between the curvature of the monolayer's leading edge and the outward motility of the edge...

journal_title：Physical biology

authors： Tarle V,Gauquelin E,Vedula SRK,D'Alessandro J,Lim CT,Ladoux B,Gov NS

更新日期：2017-05-03 00:00:00

abstract：:The asymmetric cell division cycle in Caulobacter crescentus is controlled by an elaborate molecular mechanism governing the production, activation and spatial localization of a host of interacting proteins. In previous work, we proposed a deterministic mathematical model for the spatiotemporal dynamics of six major r...

journal_title：Physical biology

authors： Li F,Subramanian K,Chen M,Tyson JJ,Cao Y

更新日期：2016-06-25 00:00:00

abstract：:By combining optical tweezers-assisted dynamic force spectroscopy experiments with fluorescence activated cell sorting (FACS), we demonstrate a new approach to reducing the data variance in measuring receptor-ligand interactions on a single molecule level by ensuring similar coating densities. Therefore, the carboxyfl...

journal_title：Physical biology

authors： Stangner T,Singer D,Wagner C,Gutsche C,Ueberschär O,Hoffmann R,Kremer F

更新日期：2013-08-01 00:00:00

abstract：:Based on the experimental evidence that translating ribosomes stabilize the mRNAs, we introduce and study a theoretical model for the dynamic shielding of mRNA by ribosomes. We present an improved fitting of published decay assay data in E. coli and show that only one third of the decay patterns are exponential. Our n...

journal_title：Physical biology

authors： Deneke C,Lipowsky R,Valleriani A

更新日期：2013-08-01 00:00:00

abstract：:The single-molecule fluorescence technique is becoming a general and mature tool to probe interactions and dynamics of biomolecules with ultra high precision and accuracy. However, nonspecific adsorption of biomolecules to the flow cells remains a major experimental riddle for the study of many complex biological syst...

journal_title：Physical biology

authors： Pan H,Xia Y,Qin M,Cao Y,Wang W

更新日期：2015-06-29 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：:How cell collectives move and deposit subunits within a developing embryo is a question of outstanding interest. In many cases, a chemotactic mechanism is employed, where cells move up or down a previously generated attractive or repulsive gradient of signalling molecules. Recent studies revealed the existence of syst...

journal_title：Physical biology

authors： Streichan SJ,Valentin G,Gilmour D,Hufnagel L

更新日期：2011-08-01 00:00:00

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

authors： Reynolds AM

更新日期：2019-04-23 00:00:00

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

authors： Rapaport DC

更新日期：2010-12-09 00:00:00

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

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

abstract：:Asexual reproduction in multicellular organisms is a complex biophysical process that is not yet well understood quantitatively. Here, we report a detailed population study for the asexual freshwater planarian Schmidtea mediterranea, which can reproduce via transverse fission due to a large stem cell contingent. Our l...

journal_title：Physical biology

authors： Dunkel J,Talbot J,Schötz EM

更新日期：2011-04-01 00:00:00

abstract：:Type I collagen is a versatile biomaterial that is widely used in medical applications due to its weak antigenicity, robust biocompatibility, and its ability to be modified for a wide array of applications. As such, collagen has become a major component of many tissue engineering scaffolds, drug delivery platforms, an...

journal_title：Physical biology

authors： Hapach LA,VanderBurgh JA,Miller JP,Reinhart-King CA

更新日期：2015-12-21 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：: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：:We propose a three-dimensional mechanical model of embryonic tissue dynamics. Mechanically coupled adherent cells are represented as particles interconnected with elastic beams which can exert non-central forces and torques. Tissue plasticity is modeled by a stochastic process consisting of a connectivity change (addi...

journal_title：Physical biology

authors： Czirok A,Isai DG

更新日期：2014-12-15 00:00:00

abstract：:We present a new particle tracking software algorithm designed to accurately track the motion of low-contrast particles against a background with large variations in light levels. The method is based on a polynomial fit of the intensity around each feature point, weighted by a Gaussian function of the distance from th...

journal_title：Physical biology

authors： Rogers SS,Waigh TA,Zhao X,Lu JR

更新日期：2007-10-09 00:00:00

abstract：:We analyze theoretically the effects of excluded-volume interactions between motors on the dynamics of a cargo driven by multiple motors. The model considered shares much in common with others recently proposed in the literature, with the addition of direct interaction between motors and motor back steps. The cargo is...

journal_title：Physical biology

authors： Bouzat S,Falo F

更新日期：2010-11-22 00:00:00

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

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

更新日期：2012-02-01 00:00:00

abstract：:In the intracellular environment, the intrinsic dynamics of microtubule filaments is often hindered by the presence of barriers of various kind, such as kinetochore complexes and cell cortex, which impact their polymerisation force and dynamical properties such as catastrophe rate. We present a theoretical study of th...

journal_title：Physical biology

authors： Yadav V,Srinivas B,Gopalakrishnan M

更新日期：2020-10-12 00:00:00