ライフサイエンスコーパス: ratchet

1 mRNA may act as "pawls" of a translocational ratchet.

2 well-adapted population in spite of Muller's ratchet.

3 also make the genome susceptible to Muller's ratchet.

4 moglobin polymerization acting as a Brownian ratchet.

5 than under background selection or Muller's ratchet.

6 e substrate are the "molecular teeth" of the ratchet.

7 the serial endosymbiotic theory and Muller's ratchet.

8 ned in terms of the inner flow fields of the ratchet.

9 X chromosome can considerably slow down the ratchet.

10 on of harmful mutations by means of Muller's ratchet.

11 recombinogenic regions by virtue of Muller's ratchet.

12 ous mutations in a process known as Muller's ratchet.

13 bstantial length and to escape from Muller's Ratchet.

14 accumulate by a mechanism known as Muller's ratchet.

15 of barriers on the track, creating an energy ratchet.

16 cation via a charge-state-dependent Brownian ratchet.

17 the ribosome likely functions as a Brownian ratchet.

18 ections to wrap a sphere--constitutes such a ratchet.

19 ational characteristics of circular granular ratchets.

20 f the ribosomal L1 stalk domain, and subunit ratcheting.

21 a model similar to a "burnt bridge" Brownian ratchet accurately describe our experimental results and

22 ponent on the particles that causes them to "ratchet" across the channel.

23 mbination of elastic-propulsion and tethered-ratchet actin-polymerization theories.

24 inked to a protonation-state, DeltapH-driven ratchet acting trans to the phi-clamp site.

25 elected mutations can accumulate by Muller's ratchet after a shutdown of recombination, as in an evol

26 During translation elongation, the ribosome ratchets along its mRNA template, incorporating each new

27 burning mechanisms such as a ParAB Brownian ratchet and a septum-associated FtsK motor.

28 x and switch regions as an anti-backtracking ratchet and an RNA hydrolysis regulator.

29 wo different parameter regimes known for the ratchet and are more accurate only in the parameter regi

30 erence among deleterious mutations (Muller's ratchet and background selection) and the fixation of be

31 of genetic hitchhiking relative to Muller's ratchet and background selection.

32 tcrossing, which allows escape from Muller's ratchet and faster spread of beneficial mutations, shoul

33 stribution of times to the next click of the ratchet and is equivalent to a Wright-Fisher model for a

34 ic comparisons with the Smoluchowski-Feynman ratchet and pawl.

35 rich Y chromosome is expected to be Muller's ratchet and/or background selection due to the large num

36 The translocation is further sped up by the ratcheting and entropic forces associated with proteins

37 bridges serving as anchoring patches for the ratcheting and rolling motions between the two subunits

38 propose that both microscopic polymerization ratchets and macroscopic stresses of the deformable acti

39 d kMTs that is generated by multiple polymer ratchets and mitotic motors coupled to tension-dependent

40 een attributed to selective sweeps, Muller's ratchet, and background selection, processes that are pr

41 deleterious recessive mutations by Muller's ratchet, and fix deleterious mutations by hitchhiking as

42 mpatible with background selection, Muller's ratchet, and local selective sweeps, but not with specie

43 -terminal part, which includes winged-helix, ratchet, and oligonucleotide/oligosaccharide-binding (OB

44 tate formation, L1 stalk closure and subunit ratcheting are loosely coupled, independent processes th

45 performance solution-processed ionic-organic ratchets are fabricated using polymer semiconductors.

46 Ratchets are nonequilibrium devices that produce directi

47 Ratchets are simple mechanical devices which combine spa

48 The Brownian ratchet arrays are not limited to DNA separation, but ca

49 proximately 100-kb DNA molecules in Brownian ratchet arrays.

50 nd motion by cytoskeletal motors and polymer ratchets as they mediate intracellular transport, organe

51 rimental data are consistent with a Brownian ratchet-based model.

52 tical intermediate sizes, such that Muller's ratchet begins to turn.

53 We propose that when S4 moves it ratchets between conformations in which one arginine aft

54 ends on whether cell shape is stabilized, or ratcheted, between pulses.

55 A Brownian ratchet (BR) mechanism has been proposed to couple actin

56 on of the central gamma subunit working as a ratchet but with structural differences that make it a u

57 (including background selection and Muller's ratchet) but are expected under recent positive selectio

58 ll-Robertson effects in the form of Muller's ratchet, but only in regions of extremely low recombinat

59 atitis virus (VSV) can recover from Muller's ratchet by replication with large effective population s

60 anisms suggested by experiments: an internal ratchet by the apical and junctional myosin condensates,

61 nonequilibrium fluctuations are rectified or ratcheted by the molecular motor to transport substrate

62 ious mutations are weakly selected, Muller's ratchet can lead to a rapid degradation of population fi

63 roscopic elastic deformation and microscopic ratchets can explain the observed bistable orientation o

64 Electronic ratchets can rectify AC signals that are extracted from

65 oduction of a supramolecular flashing energy ratchet capable of processing chemical fuel generated by

66 translocation ratchet with ComE acting as a ratcheting chaperone.

67 domain closes and ribosomal subunits adopt a ratcheted configuration.

68 Their interaction can serve as a molecular "ratchet" contributing to the migration of the mother cel

69 inimalist nature of the [2]catenane flashing ratchet design permits certain mechanistic comparisons w

70 f the catalytic center serve as two separate ratchet devices that function in concert to drive forwar

71 Powered by ATPase, the motor ratchets DNA into the capsid through the portal channel.

72 in positioning DNA relative to the helicase ratchet domain IV for efficient unwinding of forked DNA.

73 e to single-stranded DNA and to the helicase ratchet domain IV.

74 efforts by the private sector to gradually "ratchet down" some of the environmental factors that hav

75 th faster polymerization and faster Brownian-ratchet-driven motion.

76 n or power stroke coexists with the Brownian-ratchet-driven motions, and plays a crucial role in nucl

77 nal evidence for the existence of a Brownian ratchet during active T7RNAP elongation by showing that

78 ve organisms, in part because of selectivity ratcheting during these ancient extinctions, so on avera

79 The ratchet effect - the accumulation of beneficial changes

80 sion, while paternal leakage exacerbates the ratchet effect.

81 ode results do not address the origin of the ratchet effect.

82 even producing evidence of components of a "ratchet effect."

83 ls occurs by thermally assisted diffusion on ratchet energy profiles.

84 ten, demonstrating that Rab35 functions as a ratchet ensuring unidirectional movement.

85 s sentiment is ancient yet implicated in the ratcheting evolution of human ultrasocialty.

86 e tip of its beak to its mouth in a stepwise ratcheting fashion.

87 where the mechanical power transduced by the ratcheting filaments to the load is maximal.

88 nted for the mean time between clicks of the ratchet for (i) the Wright-Fisher model, (ii) a diffusio

89 e-addition state, readily transitions to the ratcheted form ("ratchetable"), indicating that the tigh

90 The ratcheted form was revealed to support GreA-dependent tr

91 cleotide addition to nascent RNA, while the "ratcheted" form is adopted for transcription inhibition.

92 their capacity to generate pushing forces by ratcheting growth is well known, conversely these versat

93 eater in D. recens, suggesting that Muller's ratchet has brought about an increased rate of substitut

94 (b) the time interval between clicks of the ratchet has, approximately, an exponential distribution

95 The operation and properties of linear ratchets have already been extensively explored.

96 models, including the widely known Brownian ratchet, have been proposed.

97 Mutation of residues along the ratchet helix alters in vitro activity in Mtr4 and TRAMP

98 ata suggest that the RP mutations within the ratchet helix impair Brr2 translocation through RNA heli

99 However, the contribution of the ratchet helix in Mtr4 activity is poorly understood.

100 e we show that strict conservation along the ratchet helix is particularly extensive for Ski2-like RN

101 These studies demonstrate that the ratchet helix modulates helicase activity and suggest th

102 w show that combining the arch deletion with ratchet helix mutations abolishes helicase activity and

103 Mutations within the ratchet helix of the Brr2 RNA binding channel result in

104 We also identify a residue on the ratchet helix that influences Mtr4 affinity for polyaden

105 The 'ratchet helix' is positioned to interact with RNA substr

106 haviour of a population after a click of the ratchet, i.e., after loss of what was the fittest class.

107 the nucleus and so functions as a molecular ratchet imposing directionality on transport.

108 biasing forces can cause the defect line to ratchet in either direction, making it possible to preci

109 We propose an electrostatic ratchet in the channel, comprised of opposing rings of c

110 ibe a three-compartment rotaxane information ratchet in which the macrocycle can be directionally tra

111 and the free-ended filaments grow as thermal ratchets in a load-sensitive manner.

112 action, work must be performed by a "thermal ratchet" in which a thermal fluctuation in Brownian moti

113 hat the ribosome uses two distinct molecular ratchets, involving both intra- and intersubunit rotatio

114 Muller's ratchet is a principle of evolutionary genetics describi

115 irectional (chiral) rotation of a mechanical ratchet is forbidden in thermal equilibrium, but becomes

116 cts that: (a) the time between clicks of the ratchet is insensitive to the value of the selection coe

117 on coordinate diagrams of motors and polymer ratchets is simplified relative to the rigorous biophysi

118 tatively described using the linear Brownian ratchet kinetic model for transcription elongation and t

119 accumulated during the operation of Muller's ratchet led to the identification of two potential mutat

120 landscape-crossing rates and show that this ratchet-like adaptive mechanism is robust in a wide spec

121 Although this ratchet-like behaviour operates in a variety of contexts

122 Two protomers undergo a ratchet-like conformational change that advances pore lo

123 A device is presented with ratchet-like current-voltage characteristics, which deli

124 We find that ATP binding induces a ratchet-like docking of the neck linker and simultaneous

125 Unless these ratchet-like epistatic substitutions are restored to the

126 ainst the walls of the microvasculature by a ratchet-like mechanism driven by the supersaturated solu

127 The structures help to explain how the ratchet-like motion of the two ribosomal subunits contri

128 ed in the present structures, coupled to the ratchet-like motion of the two subunits observed previou

129 two different functional states related by a ratchet-like motion were analyzed using real-space refin

130 o large conformational changes following the ratchet-like motion, suggesting an important role of rib

131 acts as a pawl that stabilizes the downward ratchet-like movement of beta6-alpha7 loop and alpha7-he

132 tions are driven to extinction by a Muller's ratchet-like process of element accumulation, but that l

133 el provides a near-atomic description of the ratchet-like rearrangement of the 70S ribosome seen in c

134 The ability of these crystals to undergo ratchet-like rotation is attributed to their chiral shap

135 When the surface is prepared with ratchet-like saw-teeth topography, these droplets can se

136 ulsed actomyosin meshwork contractions and a ratchet-like stabilization of cell shape drive apical co

137 w the key role of fluctuating protrusions on ratchet-like structures in driving NIH3T3 cell migration

138 A ratchet-like subunit rearrangement (RSR) occurs in the 8

139 We propose that a ratchet-like surface involving Phe105, Met109 and Leu112

140 The result is a "ratchet-like" gradient climbing behavior with drift spee

141 omal subunits reveals an intrinsic bias for "ratchet-like" intersubunit rotation.

142 RNA polymerase is a ratchet machine that oscillates between productive and b

143 -template strand, possibly in a synchronized ratcheting manner conducive to polymerase translocation.

144 oduced deleterious mutations (i.e., Muller's ratchet) may not be the dominant force imperiling nonrec

145 The ratchet mechanism constitutes a general design principle

146 oteins from a mRNP, one at a time, akin to a ratchet mechanism for mRNA export.

147 ring within the FO region support a Brownian ratchet mechanism for proton-translocation-driven rotati

148 ptional regulatory cascade, thus providing a ratchet mechanism for robust cell-cycle control.

149 aviour satisfies a requirement of a Brownian ratchet mechanism for the F motor where c-ring rotationa

150 This finding reveals a linear, non-branched ratchet mechanism for the nucleotide addition cycle in w

151 scuss a DeltapH-driven charge state Brownian ratchet mechanism for translocation, where glutamic and

152 arB system motility is driven by a diffusion ratchet mechanism in which ParB-coated plasmid both crea

153 the closed TL structure, a modified Brownian ratchet mechanism is proposed whereby thermally driven t

154 nal movement of the helicase via a molecular ratchet mechanism powered by Brownian motion.

155 We propose that a Brownian ratchet mechanism proposed earlier for the phi clamp is

156 is model, we suggest that a similar Brownian ratchet mechanism recapitulates the full range of active

157 We have identified a ratchet mechanism that can explain the observed unidirec

158 olecule studies proposed a branched Brownian ratchet mechanism that necessitates a putative secondary

159 wnian motor, which adopts the flash Brownian ratchet mechanism to pump the DNA against the increasing

160 We investigated the ratchet mechanism using anthrax toxin as a model.

161 cycling, thereby enacting a flashing energy ratchet mechanism with a minimalistic design.

162 oot of macrocyclized walkers (an information ratchet mechanism), the rear foot producing an (R)-stere

163 cular machines can operate by an information ratchet mechanism, in which knowledge of a particle's po

164 that E.coli RNAP moves by a complex Brownian ratchet mechanism, which acts prior to phosphodiester bo

165 e load is thought to operate by the Brownian ratchet mechanism, with overall organization governed by

166 ween sites on a molecular platform through a ratchet mechanism.

167 which further support the proposed diffusion-ratchet mechanism.

168 behaviour by means of a pin-release droplet ratchet mechanism.

169 he minimum-energy distribution by a Brownian ratchet mechanism.

170 t T7RNAP translocates via a passive Brownian ratchet mechanism.

171 ng T7RNAPs provides support for the Brownian ratchet mechanism.

172 nk formation drives maturation by a Brownian ratchet mechanism.

173 rapidly presumably via a hydrophobic steric ratchet mechanism.

174 del that lacks these limitations is a cyclic ratchet mechanism.

175 ution structures of these proteins suggest a ratcheting mechanism by which the KaiABC oscillator tick

176 eptide chain into the cytosol is caused by a ratcheting mechanism in which the attachment of polyubiq

177 show that BcsA translocates cellulose via a ratcheting mechanism involving a 'finger helix' that con

178 o the channel by the translating ribosome, a ratcheting mechanism is used by the endoplasmic reticulu

179 In posttranslational translocation, a ratcheting mechanism is used by the ER-lumenal chaperone

180 h biochemistry, these results demonstrate a "ratchet" mechanism involved in the unidirectional transl

181 unication suggests a new, unifying 'Brownian ratchet' mechanism, whereby ATP binding and hydrolysis b

182 Central to the power-stroke and brownian-ratchet mechanisms of protein translocation is the proce

183 polymerization, as is predicted by Brownian ratchet mechanisms.

184 eleased to direct motion through information ratchet mechanisms.

185 In the slow phase, we test two ratcheting mechanisms suggested by experiments: an inter

186 ransport mode is mechanically similar to the ratcheting mechanisms used in snakes--a group of terrest

187 We suggest that ratchet-mediated engulfment minimizes the utilization of

188 In contrast, the tethered-ratchet model assumes working filaments are untethered a

189 ss agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an

190 elastic moduli supports the Elastic Brownian Ratchet model for driving lamellipodia extension.

191 its trigger loop mutants support a Brownian ratchet model for elongation, where the incoming NTP is

192 The findings favor a diffusion-ratchet model for plasmid motion whereby partition compl

193 slocation channel, and supports the Brownian ratchet model for protein translocation.

194 Our Brownian ratchet model includes a mechanism for unfolding and a n

195 hate release, but consistent with a brownian ratchet model incorporating a secondary NTP binding site

196 n to the role of the Phe clamp in a Brownian ratchet model of translocation.

197 based propulsion: microscopic polymerization ratchet model predicts that growing and writhing actin f

198 in very good agreement with a translocation ratchet model where binding of chaperones in the peripla

199 Using the tethered polymerization ratchet model with our biochemical kinetic model for MSP

200 Here we extend the "elastic ratchet model" of Mogilner and Oster to incorporate thes

201 of preexisting models as well as a Brownian ratchet model, in which a cargo-karyopherin complex rema

202 This Brownian ratchet model, unlike the conventional carrier model, ac

203 Our results support a diffusion-ratchet model, where ParB on the plasmid chases and redi

204 The dynamics are consistent with a diffusion-ratchet model, whereby the cargo dynamically establishes

205 The "ratchet model," based on cryo-EM reconstructions of ribo

206 expected from a simple short-range Brownian ratchet model.

207 his model belongs to the class of isothermal ratchet models of TE involving the thermally driven stoc

208 low-force regime using optical tweezers and ratcheted molecular dynamics simulations.

209 study with the Pol II system suggests that a ratchet motion of the Core Factor-DNA sub-complex at ups

210 om coarse-grained simulations, including the ratchet motion, the movement together of critical bases

211 chanism of translocation where the ribosomal ratchet motion, with the aid of EF-G, drives tRNA transl

212 consistent with the experimentally observed ratchet motion.

213 ivated state facilitates translocation via a ratchet motion.

214 at begins with the eEF2/EF-G binding-induced ratcheting motion of the small ribosomal subunit.

215 our previous results, showing the well-known ratchet motions and the motions in the peptide tunnel an

216 ously been studied by considering a Brownian ratchet motor that is connected to its cargo by an elast

217 vide cytoplasmic stopover sites required for ratcheting mRNA across the nuclear pore.

218 contrast, other theories, such as molecular ratchets, neither require nor consider surface curvature

219 iasing movement in one direction: a Brownian ratchet, now proposed to explain membrane motion during

220 Here, we describe forward and reverse ratcheting of DNA templates through the alpha-hemolysin

221 ction values, the net result was a permanent ratcheting of ecosystem-wide activity to higher levels.

222 This work demonstrates the ratcheting of electrons within a highly scattering organ

223 f having neighbouring contractions, and that ratcheting of pulses prevents competition between neighb

224 alk that has been observed in the absence of ratcheting of the ribosomal subunits.

225 vements of the L1 stalk and tRNAs as well as ratcheting of the ribosome.

226 L5, H68, H69, and H38 that is caused by the ratcheting of the small subunit.

227 f prothrombin by prothrombinase is driven by ratcheting of the substrate from the zymogen to the prot

228 ght the critical dependence of the capillary ratchet on the beak's wetting properties, thus making cl

229 ion of deleterious mutations due to Muller's ratchet: once lost by stochastic drift, the most-fit cla

230 Ratchets operate by breaking time-reversal and spatial s

231 e of adaptive mutation is high, and Muller's ratchet operates only in small or asexual populations.

232 bosome, which adopts conformations involving ratcheting or rolling of the small subunit that are dist

233 The immediate effect of Muller's ratchet, overall loss of fitness, has been confirmed in

234 units rearranges in discrete steps along the ratcheting pathway.

235 ibiting dynamic instability, and acting as a ratchet permitting incorporation of new monomers and rid

236 icing, and that the sequence and function of ratchet points are evolutionarily conserved in Drosophil

237 Here we identify 197 zero nucleotide exon ratchet points in 130 introns of 115 Drosophila genes fr

238 removed in multiple steps by re-splicing at ratchet points--5' splice sites recreated after splicing

239 ntrons generated by splicing to and from the ratchet points.

240 This is the first ratchet without a ratchet potential.

241 We demonstrate that ratcheted pulses have higher probability of having neigh

242 ere weak or unratcheted pulses transition to ratcheted pulses.

243 Ratcheted reciprocating motion of a DNA/PEG copolymer th

244 ond to the Fisher-Muller effect and Muller's ratchet, respectively.

245 e sweeps, background selection, and Muller's ratchet, result in a reduction in Ne, which increase the

246 Our study thus supports the Brownian ratchet scenario of the mechano-chemical coupling in the

247 ia-Delbruck fluctuation analysis followed by ratchet selection cycles.

248 flat surface, but also self-propelled over a ratchet shaped horizontal surface.

249 Asymmetric ratchet-shaped pure copper nanorods were also found to r

250 pendent on pulses of actomyosin that lead to ratcheted shrinkage of junctions; the actomyosin pulses

251 nism for amplification that functions like a ratchet: Sound-evoked forces, acting on the basilar memb

252 trapping ssDNA inside the DNA transistor and ratcheting ssDNA base-by-base in a biasing electric fiel

253 very little is known about circular granular ratchets, startling devices able to convert vertical vib

254 protections similar to EF-G and stabilized a ratcheted state of the 70S ribosome.

255 tion and no L1 stalk-tRNA interaction, and a ratcheted state, with tRNAs in an intermediate hybrid co

256 ng of EF-G shifts the equilibrium toward the ratcheted state.

257 superconducting samples that have no spatial ratchet substrate.

258 ing spatially asymmetric potential profiles (ratchet substrates) have been realized experimentally to

259 implications of MMP-1 acting as a molecular ratchet tethered to the cell surface suggest new mechani

260 hange coupling between the layers, we form a ratchet that allows information in the form of a sharp m

261 and they can work collectively as a Brownian ratchet that directs persistent cargo movement with a Pa

262 ludes that RNA polymerase acts as a Brownian ratchet that is driven forward by the binding of incomin

263 ng DNA from histones, functions instead as a ratchet that rectifies nucleosomal fluctuations.

264 sting that SpoIIQ and SpoIIIAH function as a ratchet that renders forward membrane movement irreversi

265 the SecYEG pore and function as a molecular ratchet that uses ATP hydrolysis for physical movement o

266 it does lead to results for the rate of the ratchet that, over a wide range of parameters, are accur

267 verify the existence of optimal microfluidic ratchets that maximize rectification of initially unifor

268 ct into the ring's central cavity and act as ratchets that pull on target proteins, leading, in some

269 st promotes carbonate-forming reactions that ratchet the displacement of the macrocycle away from the

270 talysts promote a benzoylation reaction that ratchets the displacement of the macrocycle, transportin

271 he degeneration of Y chromosomes is Muller's ratchet, the perpetual stochastic loss of linkage groups

272 ote origin that allowed escape from Muller's ratchet--the origin of eukaryotic recombination, or sex-

273 DNA strands were ratcheted through the pore at median rates of 2.5-40 nuc

274 ctile process, which functions as a membrane ratchet to ensure unidirectional movement of intercalati

275 as a developmentally controlled subcellular ratchet to reduce apical area incrementally.

276 es have revealed how their timing circuit is ratcheted to be unidirectional and how they stay in sync

277 e PoTC.RRF complex reverts the ribosome from ratcheted to unratcheted state.

278 that the translocation of ssDNA changes from ratcheting to steady-sliding.

279 the mechanism by which the KaiABC oscillator ratchets unidirectionally.

280 ed in the first and in this way altruism can ratchet up to high levels.

281 munities, because human action inadvertently ratcheted up rates of soil erosion and, both intentional

282 at least, they do not play a causal role in ratcheting up political complexity.

283 e response to new information can only be to ratchet upward: Newly observed or speculated attack capa

284 F1 motor as a simplified two-state Brownian ratchet using the asymmetry of torsional elastic energy

285 This process leads to a chemically ratcheted walk along a directionally polar DNA track.

286 Using a microfabricated topographical ratchet, we show that the nucleus dictates the direction

287 his work presents a new approach to Muller's ratchet, where Haigh's model is approximately mapped int

288 lecular trap, and a diffusion aided Brownian ratchet which operated as a molecular pump.

289 the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent

290 sibility of implementing a magnetic Brownian ratchet, which may find applications in novel nanoscale

291 walk of the junction and acts as a Brownian ratchet, which walks along duplex DNA while facilitating

292 on the ribosome requires repeated cycles of ratcheting, which couples rotation of the two ribosomal

293 ts rearrange contacts with each other during ratcheting while remaining stably associated is not know

294 can be tuned by combining the topographical ratchet with a biochemical gradient of fibronectin adhes

295 the motor mechanism as an imperfect Brownian ratchet with a built-in opposing load and the chromosome

296 trongly support the model of a translocation ratchet with ComE acting as a ratcheting chaperone.

297 The ribosome is in an unusual state of ratcheting with the 30S subunit rotated clockwise relati

298 Ratchets with acute protrusions enable droplets to climb

299 ble droplets to climb steeper inclines while ratchets with sub-structures enable their direction of m

300 This is the first ratchet without a ratchet potential.