Abstract:
:To investigate the force generation properties of Chlamydomonas axonemal inner-arm dyneins in response to external force, we analyzed microtubule gliding on dynein-coated surfaces under shear flow. When inner-arm dynein c was used, microtubule translocation in the downstream direction accelerated with increasing flow speed in a manner that depended on the dynein density and ATP concentration. In contrast, the microtubule translocation velocity in the upstream direction was unaffected by the flow speed. The number of microtubules on the glass surface was almost constant with and without flow, suggesting that gliding acceleration was not simply caused by weakened dynein-microtubule binding. With other inner-arm dynein species, the microtubule gliding velocity was unaffected by the flow regardless of the flow direction or nucleotide concentration. The flow-generated force acting on a single dynein was estimated to be as small as approximately 0.03 pN/dynein. These results indicate that dynein c possesses a ratchetlike property that allows acceleration only in one direction by a very small external force. This property should be important for slow- and fast-moving dyneins to function simultaneously within the axoneme.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Kikushima K,Kamiya Rdoi
10.1016/j.bpj.2009.07.010subject
Has Abstractpub_date
2009-09-16 00:00:00pages
1657-62issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(09)01230-2journal_volume
97pub_type
杂志文章abstract::We combine ensemble and single-molecule spectroscopy to gain insight into the energy transfer between chlorophylls (Chls) in peridinin-chlorophyll-protein (PCP) complexes reconstituted with Chl a, Chl b, as well as both Chl a and Chl b. The main focus is the heterochlorophyllous system (Chl a/b-N-PCP), and reference i...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.112094
更新日期:2007-11-01 00:00:00
abstract::Voltage-gated ion channels are crucial for regulation of electric activity of excitable tissues such as nerve cells, and play important roles in many diseases. During activation, the charged S4 segment in the voltage sensor domain translates across a hydrophobic core forming a barrier for the gating charges. This barr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.11.3827
更新日期:2013-01-08 00:00:00
abstract::Immature human immunodeficiency virus (HIV) virions have a lattice of Gag and Gag-Pol proteins anchored to the lumen of their envelope. Using electron microscopy, we demonstrate that HIV virus-like particles (VLPs) assembled by the viral protein Gag and tagged at its C-terminus with the fluorescent protein Dendra2 hav...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.06.023
更新日期:2020-08-04 00:00:00
abstract::Helix-coil transitions in polyalanine molecules of length 10 are studied by multi-canonical Monte Carlo simulations. The solvation effects are included by either a distance-dependent dielectric permittivity or by a term that is proportional to the solvent-accessible surface area of the peptide. We found a strong depen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75668-3
更新日期:2002-06-01 00:00:00
abstract::Steady-state and time-resolved fluorescence spectroscopy was used to follow the local and global changes in structure and dynamics during chemical and thermal denaturation of unlabeled human serum albumin (HSA) and HSA with an acrylodan moiety bound to Cys34. Acrylodan fluorescence was monitored to obtain information ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77598-8
更新日期:1998-08-01 00:00:00
abstract::Yeast cytosine deaminase, a zinc metalloenzyme, catalyzes the deamination of cytosine to uracil. Experimental and computational evidence indicates that the rate-limiting step is product release, instead of the chemical reaction step. In this work, we use molecular dynamics to suggest ligand exit paths. Simulation at 3...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.098921
更新日期:2007-04-01 00:00:00
abstract::This paper describes a new technique that can be used to study chloroplast volume regulation in vivo. Nuclear magnetic resonance spectroscopy was used to measure relative amounts of chloroplast water in Acer platanoides leaves as they dried in air, and also in leaf disks exposed to aqueous polyethylene glycol, sucrose...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81930-6
更新日期:1992-05-01 00:00:00
abstract::The traditional theory of transport across capillary membranes via a laminar Poiseuille flow is shown to be invalid. It is demonstrated that the random, diffusive nature of the molecular flow and interactions with the "pore" walls play an important role in the transport process. Neither the continuum Navier-Stokes the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(73)86026-6
更新日期:1973-08-01 00:00:00
abstract::Metallic nanoparticles have opened the possibility of imaging, tracking, and manipulating biological samples without time limitations. Their low photoluminescence quantum yield, however, makes them hard to detect under high background conditions. In this study we show that it is possible to image gold nanorods by dete...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.10.035
更新日期:2016-12-06 00:00:00
abstract::Intramembrane charge movement (Q), Ca(2+) conductance (G(m)) through the dihydropyridine-sensitive L-type Ca(2+) channel (DHPR) and intracellular Ca(2+) fluorescence (F) have been recorded simultaneously in flexor digitorum brevis muscle fibers of adult mice, using the whole-cell configuration of the patch-clamp techn...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(99)77104-3
更新日期:1999-11-01 00:00:00
abstract::Microtubules are cytoskeletal filaments whose self-assembly occurs by abrupt switching between states of roughly constant growth and shrinkage, a process known as dynamic instability. Understanding the mechanism of dynamic instability offers potential for controlling microtubule-dependent cellular processes such as ne...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79953-2
更新日期:1995-09-01 00:00:00
abstract::We developed a model of the rat ventricular myocyte at room temperature to predict the relative effects of different mechanisms on the cause of the slow increase in force in response to a step change in muscle length. We performed simulations in the presence of stretch-dependent increases in flux through the Na(+)-H(+...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.095463
更新日期:2007-06-01 00:00:00
abstract::The oligomeric structure was determined for four recombinant kinesin derivatives containing N-terminal fragments of the kinesin alpha-subunit. Some of the proteins were dimeric (two-headed) molecules with mechanochemical properties similar to those of intact kinesin. Comparison of the primary and quaternary structures...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract::A dimeric alamethicin analog with lysine at position 18 in the sequence (alm-K18) was previously shown to form stable anion-selective channels in membranes at pH 7.0 [Starostin, A. V., R. Butan, V. Borisenko, D. A. James, H. Wenschuh, M. S. Sansom, and G. A. Woolley. 1999. Biochemistry. 38:6144-6150]. To probe the cha...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(00)76688-4
更新日期:2000-03-01 00:00:00
abstract::Reattachment and healing of tendon to bone poses a persistent clinical challenge and often results in poor outcomes, in part because the mechanisms that imbue the uninjured tendon-to-bone attachment with toughness are not known. One feature of typical tendon-to-bone surgical repairs is direct attachment of tendon to s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2014.09.049
更新日期:2015-01-20 00:00:00
abstract::Based on differences between the x-ray crystal structures of ligand-bound and unbound forms, the activation of the erythropoietin receptor (EPOR) was initially proposed to involve a cross-action scissorlike motion. However, the validity of the motions involved in the scissorlike model has been recently challenged. Her...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.12.042
更新日期:2017-02-28 00:00:00
abstract::The switch 1 region of myosin forms a lid over the nucleotide phosphates as part of a structure known as the phosphate-tube. The homologous region in kinesin-family motors is more open, not interacting with the nucleotide. We used molecular dynamics (MD) simulations to examine a possible displacement of switch 1 of th...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76092-4
更新日期:2001-03-01 00:00:00
abstract::We propose mechanisms by which the transmembrane domain of vesicular stomatitis virus (VSV-TMD) promotes both initiation of fusion and formation of a fusion pore. Time courses of polyethyleneglycol (PEG)-mediated fusion of 25 nm small unilamellar vesicles composed of dioleoylphosphatidylcholine, dioleoylphosphatidylet...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2014.03.053
更新日期:2014-09-16 00:00:00
abstract::Human posttranslationally modified N-ras oncogenes are known to be implicated in numerous human cancers. Here, we applied a combination of experimental and computational techniques to determine structural and dynamical details of the lipid chain modifications of an N-ras heptapeptide in 1,2-dimyristoyl-sn-glycero-3-ph...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104562
更新日期:2007-10-15 00:00:00
abstract::Aqueous proline solutions are deceptively simple as they can take on complex roles such as protein chaperones, cryoprotectants, and hydrotropic agents in biological processes. Here, a molecular level picture of proline/water mixtures is developed. Car-Parrinello ab initio molecular dynamics (CPAIMD) simulations of aqu...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.134916
更新日期:2008-12-01 00:00:00
abstract::The single photon response in vertebrate phototransduction is highly reproducible despite a number of random components of the activation cascade, including the random activation site, the random walk of an activated receptor, and its quenching in a random number of steps. Here we use a previously generated and tested...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.114058
更新日期:2008-05-01 00:00:00
abstract::The photoreceptor rhodopsin is a G-protein coupled receptor that has recently been proposed to exist as a dimer or higher order oligomer, in contrast to the previously described monomer, in retinal rod outer segment disk membranes. Rhodopsin exhibits considerably greater thermal stability than opsin (the bleached form...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.128868
更新日期:2008-09-15 00:00:00
abstract::Fluorescence fluctuation spectroscopy has become an important measurement tool for investigating molecular dynamics, molecular interactions, and chemical kinetics in biological systems. Although the basic theory of fluctuation spectroscopy is well established, it is not widely recognized that saturation of the fluores...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.052779
更新日期:2005-09-01 00:00:00
abstract::The processes of cell growth and budding of the yeast cells Saccharomyces cerevisiae, which were gently immobilized on 3% agar and submerged in culture medium, were successfully imaged with an atomic force microscope for 6-7 h. Similar experiments on chemically fixed cells did not detect any appreciable change in thei...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80147-5
更新日期:1995-12-01 00:00:00
abstract::A systematic new approach to derive multiscale coarse-grained (MS-CG) models has been recently developed. The approach employs information from atomistically detailed simulations to derive CG forces and associated effective potentials. In this work, the MS-CG methodology is extended to study two peptides representing ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.094425
更新日期:2007-06-15 00:00:00
abstract::It has been accepted that the force produced by a skeletal muscle myofibril depends on its cross-sectional area but not on the number of active sarcomeres because they are arranged in series. However, a previous study performed by our group showed that blocking actomyosin interactions within an activated myofibril and...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.03.007
更新日期:2020-04-21 00:00:00
abstract::Fusion is a crucial event in the infection of animal cells by enveloped viruses (e.g., HIV or influenza). Viral fusion is mediated by glycoproteins, spanning the viral envelope, which attach to a membrane surface and induce fusion of the viral envelope to the cellular membrane. Influenza fusion protein (hemagglutinin)...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78175-X
更新日期:1997-09-01 00:00:00
abstract::Using a model for catalysis of a dynamic equilibrium, the role of constraint in catalysis is quantified. The intrinsic rigidity of proteins is shown to be insufficient to constrain the activated complexes of enzymes, irrespective of the mechanism. However, when minimization of the surface excess free energy of water s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75575-6
更新日期:2002-05-01 00:00:00
abstract::We revisit a heteropolymer collapse theory originally introduced to explore how the balance between hydrophobic interactions and configurational entropy determines the thermal stability of globular proteins at ambient pressure. We generalize the theory by introducing a basic statistical mechanical treatment for how pr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.081802
更新日期:2006-10-01 00:00:00
abstract::Chiral objects which scatter and absorb preferentially left versus right circularly polarized light give rise to bright-field circular dichroism (CD) images containing contributions from both these two phenomena. These contributions are separated and characterized mathematically, and the effect of the dimensions of th...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82334-7
更新日期:1991-06-01 00:00:00