Mechanical properties of branched actin filaments.

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：: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

authors： Hayot F,Jayaprakash C

更新日期：2004-12-01 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：: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

authors： Rodrigues AM,Almeida AC,Infantosi AF

更新日期：2008-07-29 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：: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：:This paper gives an overview of the coarse-grained models of phospholipids recently developed by the authors in the frame of a hybrid particle-field molecular dynamics technique. This technique employs a special class of coarse-grained models that are gaining popularity because they allow simulations of large scale sy...

journal_title：Physical biology

authors： Milano G,Kawakatsu T,De Nicola A

更新日期：2013-08-01 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：: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：:This special issue consists of 11 original papers that elaborate on work presented at the Fourth Annual q-bio Conference on Cellular Information Processing, which was held on the campus of St John's College in Santa Fe, New Mexico, USA, 11-14 August 2010. Now in its fourth year, the q-bio conference has changed consid...

journal_title：Physical biology

authors： Nemenman I,Faeder JR,Hlavacek WS,Jiang Y,Wall ME,Zilman A

更新日期：2011-10-01 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：: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

authors： Shahriyari L,Komarova NL

更新日期：2015-07-31 00:00:00

abstract：:Shelter-in-place and other confinement strategies implemented in the current COVID-19 pandemic have created stratified patterns of contacts between people: close contacts within households and more distant contacts between the households. The epidemic transmission dynamics is significantly modified as a consequence. W...

journal_title：Physical biology

authors： Huber G,Kamb M,Kawagoe K,Li LM,Veytsman B,Yllanes D,Zigmond D

更新日期：2020-10-21 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：:Gene expression is an intrinsically noisy process, typically, producing mRNAs and proteins in bursts. An important description of such stochastic processes can be done in terms of the mean first passage time (MFPT), i.e., the time taken by mRNAs/proteins to reach a particular threshold. We study the role of burstiness...

journal_title：Physical biology

authors： Shreshtha M,Surendran A,Ghosh A

更新日期：2016-05-20 00:00:00

abstract：:Electrostatic interaction is the driving force for the encapsulation by virus coat proteins of nanoparticles such as quantum dots, gold particles and magnetic beads for, e.g., imaging and therapeutic purposes. In recent experimental work, Daniel et al (2010 ACS Nano 4 3853-60) found the encapsulation efficiency to sen...

journal_title：Physical biology

authors： Lin HK,van der Schoot P,Zandi R

更新日期：2012-12-01 00:00:00

abstract：:Recently, major progress has been made to develop computational models to predict and explain the mechanisms and behaviors of gene regulation. Here, we review progress on how these mechanisms and behaviors have been interpreted with analog models, where cell properties continuously modulate transcription, and digital ...

journal_title：Physical biology

authors： Munsky B,Neuert G

更新日期：2015-06-18 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：:Voltage-dependent ion channels determine the electric properties of axonal cell membranes. They not only allow the passage of ions through the cell membrane, but also contribute to an additional charging of the cell membrane resulting in the so-called capacitance loading. The switching of the channel gates between an ...

journal_title：Physical biology

authors： Schmid G,Goychuk I,Hänggi P

更新日期：2006-11-22 00:00:00

abstract：:'ENVIRONMENT' is a computational platform that has been developed in the last few years with the aim to simulate stochastically the dynamics and stability of chemically reacting protocellular systems. Here we present and describe some of its main features, showing how the stochastic kinetics approach can be applied to...

journal_title：Physical biology

authors： Mavelli F,Ruiz-Mirazo K

更新日期：2010-08-11 00:00:00

abstract：:Modeling the spatiotemporal dynamics of biochemical reaction systems at single-molecule resolution has become feasible with the increase of computing power and is applied especially to cellular signal transduction. For an association reaction the two molecules have to be in contact. Hence, a physically faithful model ...

journal_title：Physical biology

authors： Klann M,Koeppl H

更新日期：2013-08-01 00:00:00

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：: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

authors： Song G

更新日期：2020-10-07 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：: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 Golgi apparatus has intrigued researchers since its discovery and despite the advances, there are still many open questions in regards to its shape and function. We propose a mechanical model of Golgi apparatus stack and explain its most elementary geometrical properties: the equilibrium number of cisternae, the s...

journal_title：Physical biology

authors： Jelerčič U

更新日期：2019-09-05 00:00:00

abstract：:Tumors consist of multiple cell sub-populations including cancer stem cells (CSCs), transiently amplifying cells and terminally differentiated cells (TDCs), with the CSC fraction dictating the aggressiveness of the tumor and drug sensitivity. In epithelial cancers, tumor growth is influenced greatly by properties of t...

journal_title：Physical biology

authors： Kumar S,Kulkarni R,Sen S

更新日期：2016-04-29 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

abstract：:Identifying the cues followed by cells is key to understand processes as embryonic development, tissue homeostasis, or several pathological conditions. Based on a durotaxis model, it is shown that cells moving on predeformed thin elastic membrane follow the direction of increasing strain of the substrate. This mechani...

journal_title：Physical biology

authors： Márquez S,Reig G,Concha M,Soto R

更新日期：2019-09-06 00:00:00

abstract：:Traditional experimental biology has provided a mechanistic understanding of cancer in which the malignancy develops through the acquisition of mutations that disrupt cellular processes. Several drugs developed to target such mutations have now demonstrated clinical value. These advances are unequivocal testaments to ...

journal_title：Physical biology

authors： Stites EC

更新日期：2013-04-01 00:00:00