Does axonemal dynein push, pull, or oscillate?

Lindemann, Charles B.; Hunt, Alan

doi:10.1002/cm.10148

Cited by 32 publications

(33 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2 and 4, white arrowheads). It was proposed that linkage of heads to A-tubules may be important in force production (30). The tethering structures observed here might be one of the components that associate with dynein heavy chains, as proposed for Chlamydomonas dynein (31).…”

Section: Resultssupporting

confidence: 58%

Dynein pulls microtubules without rotating its stalk

Ueno

Yasunaga²,

Shingyoji³

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Dynein is a microtubule motor that powers motility of cilia and flagella. There is evidence that the relative sliding of the doublet microtubules is due to a conformational change in the motor domain that moves a microtubule bound to the end of an extension known as the stalk. A predominant model for the movement involves a rotation of the head domain, with its stalk, toward the microtubule plus end. However, stalks bound to microtubules have been difficult to observe. Here, we present the clearest views so far of stalks in action, by observing sea urchin, outer arm dynein molecules bound to microtubules, with a new method, ''cryopositive stain'' electron microscopy. The dynein molecules in the complex were shown to be active in in vitro motility assays. Analysis of the electron micrographs shows that the stalk angles relative to microtubules do not change significantly between the ADP⅐vanadate and no-nucleotide states, but the heads, together with their stalks, shift with respect to their A-tubule attachments. Our results disagree with models in which the stalk acts as a lever arm to amplify structural changes. The observed movement of the head and stalk relative to the tail indicates a new plausible mechanism, in which dynein uses its stalk as a grappling hook, catching a tubulin subunit 8 nm ahead and pulling on it by retracting a part of the tail (linker).electron microscopy ͉ molecular motor

show abstract

Section: Resultssupporting

confidence: 58%

Dynein pulls microtubules without rotating its stalk

Ueno

Yasunaga²,

Shingyoji³

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Following an analysis of the flexibility of the dynein stem, we proposed that force transmission between the doublets would be severely limited if there were not some mechanism to stabilize the dynein head during the power stroke (Lindemann & Hunt 2003). In addition, work from Warner's laboratory (Warner & Mitchell 1978, Zanetti et al 1979 showed beyond any doubt that the formation of rigor bridges physically reduces the size of Rigor and relaxed configurations of dynein.…”

Section: Seeing Is Believingmentioning

confidence: 99%

The geometric clutch at 20: stripping gears or gaining traction?

Lindemann

Lesich

2015

Reproduction

View full text Add to dashboard Cite

It has been 20 years since the geometric clutch (GC) hypothesis was first proposed. The core principle of the GC mechanism is fairly simple. When the axoneme of a eukaryotic flagellum is bent, mechanical stress generates forces transverse to the outer doublets (t-forces). These t-forces can push doublets closer together or pry them apart. The GC hypothesis asserts that changes in the inter-doublet spacing caused by t-forces are responsible for the activation and deactivation of the dynein motors, that creates the beat cycle. A series of computer models utilizing the clutch mechanism has shown that it can simulate ciliary and flagellar beating. The objective of the present review is to assess where things stand with the GC hypothesis in the clarifying light of new information. There is considerable new evidence to support the hypothesis. However, it is also clear that it is necessary to modify some of the original conceptions of the hypothesis so that it can be consistent with the results of recent experimental and ultrastructural studies. In particular, dynein deactivation by t-forces must be able to occur with dyneins that remain attached to the B-subtubule of the adjacent doublet.Reproduction (2015) 150 R45-R53

show abstract

“…Progress is being made in this direction. Recently, some information on the elastic behavior of the dynein heavy chain has become available (Burgess et al, 2003;Lindemann and Hunt, 2003). Application of new techniques such as optical trapping and atomic force microscopy to cilia and flagella is expanding our knowledge of the mechanics of the axoneme (Shingyoji et al, 1998;Sakakibara et al, 1999Sakakibara et al, , 2004.…”

Section: Tests: Present and Futurementioning

confidence: 99%

Testing the Geometric Clutch hypothesis

Lindemann¹

2004

Biology of the Cell

Self Cite

View full text Add to dashboard Cite

The Geometric Clutch hypothesis is based on the premise that transverse forces (t-forces) acting on the outer doublets of the eukaryotic axoneme coordinate the action of the dynein motors to produce flagellar and ciliary beating. T-forces result from tension and compression on the outer doublets when a bend is present on the flagellum or cilium. The t-force acts to pry the doublets apart in an active bend, and push the doublets together when the flagellum is passively bent and thus could engage and disengage the dynein motors. Computed simulations of this working mechanism have reproduced the beating pattern of simple cilia and flagella, and of mammalian sperm. Cilia-like beating, with a clearly defined effective and recovery stroke, can be generated using one uniformly applied switching algorithm. When the mechanical properties and dimensions appropriate to a specific flagellum are incorporated into the model the same algorithm can simulate a sea urchin or bull sperm-like beat. The computed model reproduces many of the observed behaviors of real flagella and cilia. The model can duplicate the results of outer arm extraction experiments in cilia and predicted two types of arrest behavior that were verified experimentally in bull sperm. It also successfully predicted the experimentally determined nexin elasticity. Calculations based on live and reactivated sea urchin and bull sperm yielded a value of 0.5 nN/µm for the t-force at the switch-point. This is a force sufficient to overcome the shearing force generated by all the dyneins on one micron of outer doublet. A t-force of this magnitude should produce substantial distortion of the axoneme at the switch-point, especially in spoke or spoke-head deficient motile flagella. This concrete and verifiable prediction is within the grasp of recent advances in imaging technology, specifically cryoelectron microscopy and atomic force microscopy.

show abstract

Does axonemal dynein push, pull, or oscillate?

Cited by 32 publications

References 35 publications

Dynein pulls microtubules without rotating its stalk

Dynein pulls microtubules without rotating its stalk

The geometric clutch at 20: stripping gears or gaining traction?

Testing the Geometric Clutch hypothesis

Contact Info

Product

Resources

About