scholarly journals The Interaction of Neurofilaments with the Microtubule Motor Cytoplasmic Dynein

2004 ◽  
Vol 15 (11) ◽  
pp. 5092-5100 ◽  
Author(s):  
Oliver I. Wagner ◽  
Jennifer Ascaño ◽  
Mariko Tokito ◽  
Jean-Francois Leterrier ◽  
Paul A. Janmey ◽  
...  
Keyword(s):  
Axonal Transport ◽  
Specific Interaction ◽  
Cytoplasmic Dynein ◽  
Live Cells ◽  
Slow Axonal Transport ◽  
Force Microscopy ◽  
Atomic Force ◽  
Microtubule Motors ◽  
Microtubule Motor ◽  
Physical Interactions

Neurofilaments are synthesized in the cell body of neurons and transported outward along the axon via slow axonal transport. Direct observation of neurofilaments trafficking in live cells suggests that the slow outward rate of transport is due to the net effects of anterograde and retrograde microtubule motors pulling in opposition. Previous studies have suggested that cytoplasmic dynein is required for efficient neurofilament transport. In this study, we examine the interaction of neurofilaments with cytoplasmic dynein. We used fluid tapping mode atomic force microscopy to visualize single neurofilaments, microtubules, dynein/dynactin, and physical interactions between these neuronal components. AFM images suggest that neurofilaments act as cargo for dynein, associating with the base of the motor complex. Yeast two-hybrid and affinity chromatography assays confirm this hypothesis, indicating that neurofilament subunit M binds directly to dynein IC. This interaction is blocked by monoclonal antibodies directed either to NF-M or to dynein. Together these data suggest that a specific interaction between neurofilament subunit M and cytoplasmic dynein is involved in the saltatory bidirectional motility of neurofilaments undergoing axonal transport in the neuron.

scholarly journals An Atomic Force Microscopy Study of Live Cells and Biofilms of Rhizobium Leguminosarum

2011 ◽  
Vol 100 (3) ◽  
pp. 162a
Author(s):  
Jun Dong ◽  
Elizabeth M. Vanderlinde ◽  
Christopher K. Yost ◽  
Tanya E.S. Dahms
Keyword(s):  
Atomic Force Microscopy ◽  
Rhizobium Leguminosarum ◽  
Microscopy Study ◽  
Live Cells ◽  
Atomic Force Microscopy Study ◽  
Force Microscopy ◽  
Atomic Force

scholarly journals Dynactin is required for bidirectional organelle transport

2003 ◽  
Vol 160 (3) ◽  
pp. 297-301 ◽  
Author(s):  
Sean W. Deacon ◽  
Anna S. Serpinskaya ◽  
Patricia S. Vaughan ◽  
Monica Lopez Fanarraga ◽  
Isabelle Vernos ◽  
...  
Keyword(s):  
Cell Types ◽  
Cytoplasmic Dynein ◽  
Opposite Polarity ◽  
Model System ◽  
Organelle Transport ◽  
Transport Activity ◽  
Microtubule Motors ◽  
Microtubule Motor ◽  
Dynactin Complex ◽  
Binding Subunit

Kinesin II is a heterotrimeric plus end–directed microtubule motor responsible for the anterograde movement of organelles in various cell types. Despite substantial literature concerning the types of organelles that kinesin II transports, the question of how this motor associates with cargo organelles remains unanswered. To address this question, we have used Xenopus laevis melanophores as a model system. Through analysis of kinesin II–mediated melanosome motility, we have determined that the dynactin complex, known as an anchor for cytoplasmic dynein, also links kinesin II to organelles. Biochemical data demonstrates that the putative cargo-binding subunit of Xenopus kinesin II, Xenopus kinesin II–associated protein (XKAP), binds directly to the p150Glued subunit of dynactin. This interaction occurs through aa 530–793 of XKAP and aa 600–811 of p150Glued. These results reveal that dynactin is required for transport activity of microtubule motors of opposite polarity, cytoplasmic dynein and kinesin II, and may provide a new mechanism to coordinate their activities.

The Specific Binding between Galactose Group and Ricinus Communis Agglutinin (RCA) Investigated with Microcantilever

2012 ◽  
Vol 531-532 ◽  
pp. 600-604
Author(s):  
Hui Yong Zhang ◽  
Ji Hu ◽  
Hui Min Liu
Keyword(s):  
Atomic Force Microscopy ◽  
Self Assembly ◽  
Control Experiment ◽  
Ricinus Communis ◽  
Specific Binding ◽  
Specific Interaction ◽  
Protein Layer ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ricinus Communis Agglutinin

The specific recognization between galactose group and Ricinus Communis Agglutinin (RCA) was investigated by microcantilever. The gold side of the microcantilever was covalently bound with N-galactose, RCA and asialofetuin (ASF) via mixed self assembly monolayer of 11-mercaptoundecanoic acid and 6-mercaptohexanol, respectively. After adding RCA into the flowing cell, the deflection could be observed on the N-galactose or ASF modified microcantilever. Meanwhile, the deflection could also be observed after ASF bound to the RCA modified microcantilever. In order to prove that the deflection is caused by the specific interaction between the galactose group and RCA, bovine serum albumin (BSA) was introduced into the flowing cell as control experiment and no obvious deflection was observed. The specific interaction was also confirmed by the evidence that the bound protein layer can be mechanically removed with atomic force microscopy nanolithography technology.

Resonance compensating chirp mode for mapping the rheology of live cells by high-speed atomic force microscopy

2018 ◽  
Vol 113 (9) ◽  
pp. 093701 ◽  
Author(s):  
Marc Schächtele ◽  
Erik Hänel ◽  
Tilman E. Schäffer
Keyword(s):  
Atomic Force Microscopy ◽  
High Speed ◽  
Live Cells ◽  
Force Microscopy ◽  
Atomic Force

Fuzzy logic algorithm to extract specific interaction forces from atomic force microscopy data

2000 ◽  
Vol 71 (5) ◽  
pp. 2082-2086 ◽  
Author(s):  
Sandor Kasas ◽  
Beat M. Riederer ◽  
Stefan Catsicas ◽  
Brunero Cappella ◽  
Giovanni Dietler
Keyword(s):  
Atomic Force Microscopy ◽  
Fuzzy Logic ◽  
Specific Interaction ◽  
Atomic Force Microscopy Data ◽  
Interaction Forces ◽  
Fuzzy Logic Algorithm ◽  
Force Microscopy ◽  
Atomic Force ◽  
Microscopy Data

scholarly journals CLIP-170 Homologue and NUDE Play Overlapping Roles in NUDF Localization in Aspergillus nidulans

2006 ◽  
Vol 17 (4) ◽  
pp. 2021-2034 ◽  
Author(s):  
Vladimir P. Efimov ◽  
Jun Zhang ◽  
Xin Xiang
Keyword(s):  
Aspergillus Nidulans ◽  
Fluorescent Protein ◽  
Cytoplasmic Dynein ◽  
Live Cells ◽  
Physiological Conditions ◽  
Physical Interactions ◽  
Cytoplasmic Microtubules ◽  
Growth Promoting ◽  
Green Fluorescent ◽  
Hyphal Tip

Proteins in the cytoplasmic dynein pathway accumulate at the microtubule plus end, giving the appearance of comets when observed in live cells. The targeting mechanism for NUDF (LIS1/Pac1) of Aspergillus nidulans, a key component of the dynein pathway, has not been clear. Previous studies have demonstrated physical interactions of NUDF/LIS1/Pac1 with both NUDE/NUDEL/Ndl1 and CLIP-170/Bik1. Here, we have identified the A. nidulans CLIP-170 homologue, CLIPA. The clipA deletion did not cause an obvious nuclear distribution phenotype but affected cytoplasmic microtubules in an unexpected manner. Although more microtubules failed to undergo long-range growth toward the hyphal tip at 32°C, those that reached the hyphal tip were less likely to undergo catastrophe. Thus, in addition to acting as a growth-promoting factor, CLIPA also promotes microtubule dynamics. In the absence of CLIPA, green fluorescent protein-labeled cytoplasmic dynein heavy chain, p150Glued dynactin, and NUDF were all seen as plus-end comets at 32°C. However, under the same conditions, deletion of both clipA and nudE almost completely abolished NUDF comets, although nudE deletion itself did not cause a dramatic change in NUDF localization. Based on these results, we suggest that CLIPA and NUDE both recruit NUDF to the microtubule plus end. The plus-end localization of CLIPA itself seems to be regulated by different mechanisms under different physiological conditions. Although the KipA kinesin (Kip2/Tea2 homologue) did not affect plus-end localization of CLIPA at 32°C, it was required for enhancing plus-end accumulation of CLIPA at an elevated temperature (42°C).

Comparison study of live cells by atomic force microscopy, confocal microscopy, and scanning electrochemical microscopy

2007 ◽  
Vol 85 (3) ◽  
pp. 175-183 ◽  
Author(s):  
Xiaocui Zhao ◽  
Nils O Petersen ◽  
Zhifeng Ding
Keyword(s):  
Atomic Force Microscopy ◽  
Confocal Microscopy ◽  
Scanning Electrochemical Microscopy ◽  
Time Lapse ◽  
Live Cells ◽  
Tapping Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Tapping Mode Afm ◽  
Electrochemical Microscopy

In this report, three kinds of scanning probe microscopy techniques, atomic force microscopy (AFM), confocal microscopy (CM), and scanning electrochemical microscopy (SECM), were used to study live cells in the physiological environment. Two model cell lines, CV-1 and COS-7, were studied. Time-lapse images were obtained with both contact and tapping mode AFM techniques. Cells were more easily scratched or moved by contact mode AFM than by tapping mode AFM. Detailed surface structures such as filamentous structures on the cell membrane can be obtained and easily discerned with tapping mode AFM. The toxicity of ferrocenemethanol (Fc) on live cells was studied by CM in reflection mode by recording the time-lapse images of controlled live cells and live cells with different Fc concentrations. No significant change in the morphology of cells was caused by Fc. Cells were imaged by SECM with Fc as the mediator at a biased potential of 0.35 V (vs. Ag/AgCl with a saturated KCl solution). Cells did not change visibly within 1 h, which indicated that SECM was a noninvasive technique and thus has a unique advantage for the study of soft cells, since the electrode scanned above the cells instead of in contact with them. Reactive oxygen species (ROS) generated by the cells were detected and images based on these chemical species were obtained. It is demonstrated that SECM can provide not only the topographical images but also the images related to the chemical or biochemical species released by the live cells.Key words: live cells, atomic force microscopy, confocal microscopy, scanning electrochemical microscopy.

AFM: The art of touching molecules

1994 ◽  
Vol 52 ◽  
pp. 1048-1049
Author(s):  
V. T. Moy ◽  
U. G. Hofmann ◽  
M. Benoit ◽  
D. Wagner ◽  
M. Ludwig ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Protein Complexes ◽  
Large Degree ◽  
Live Cells ◽  
Force Microscopy ◽  
Langmuir Blodgett ◽  
Atomic Force ◽  
Supramolecular Arrangements ◽  
Langmuir Blodgett Films ◽  
Broad Variety

During recent years the atomic force microscopy (AFM) has evolved into an extremely useful instrument in life sciences. Particularly the option of this novel technique to operate under quasi physiological conditions and in real time has initiated a broad spectrum of new experiments. As a result, structural and micro-mechanical properties of supramolecular arrangements like molecular films and protein complexes were elucidated. Dynamic processes in live cells were recorded at unparalleled resolution and molecular interactions were investigated. Selected examples of such aspects will be the topic of this lecture.The AFM has improved drastically the understanding of the molecular structure of Langmuir-Blodgett films. LB films have in turn evolved into standards for the improvement of the understanding of the fundamental imaging mechanisms because of several reasons: they may be formed from a broad variety of substances and their molecular packing can be varied and controlled to a large degree at the air water interface prior to transfer, allowing the intelligent design of certain surface properties like roughness and charge density or micro-mechanical properties.

Sign in / Sign up

Export Citation Format

Share Document