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Nature Communications Jul 2019Cytoplasmic dynein is the most complex cytoskeletal motor protein and is responsible for numerous biological functions. Essential to dynein's function is its capacity to...
Cytoplasmic dynein is the most complex cytoskeletal motor protein and is responsible for numerous biological functions. Essential to dynein's function is its capacity to respond anisotropically to tension, so that its microtubule-binding domains bind microtubules more strongly when under backward load than forward load. The structural mechanisms by which dynein senses directional tension, however, are unknown. Using a combination of optical tweezers, mutagenesis, and chemical cross-linking, we show that three structural elements protruding from the motor domain-the linker, buttress, and stalk-together regulate directional tension-sensing. We demonstrate that dynein's anisotropic response to directional tension is mediated by sliding of the coiled-coils of the stalk, and that coordinated conformational changes of dynein's linker and buttress control this process. We also demonstrate that the stalk coiled-coils assume a previously undescribed registry during dynein's stepping cycle. We propose a revised model of dynein's mechanochemical cycle which accounts for our findings.
Topics: Amino Acid Sequence; Biomechanical Phenomena; Dyneins; Microtubules; Models, Biological; Mutagenesis; Optical Tweezers; Protein Domains; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins
PubMed: 31350388
DOI: 10.1038/s41467-019-11231-8 -
Andrology Nov 2022The dynein-related genes may have a role in the etiology of male infertility, particularly in cases of impaired sperm motility. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The dynein-related genes may have a role in the etiology of male infertility, particularly in cases of impaired sperm motility.
OBJECTIVES
The goal of this review is to compile a list of the most important dynein-related candidate genes that may contribute to male factor infertility.
MATERIALS AND METHODS
Databases were searched using the keywords "dynein," "male," "infertility," and by applying strict inclusion criteria. A meta-analysis was also performed by using the eligible case-control studies. The odd ratios (ORs), the Z-test score, and the level of significance were determined using a fixed model with a p value of 0.05. Funnel plots were used to check for publication bias.
RESULTS
There were 35 studies that met the inclusion criteria. There were a total of 15 genes responsible for the production of dynein structural proteins, the production of dynein assembling factors, and potentially associated with male infertility. A total of five case-control studies were eligible for inclusion in the meta-analysis. Variants in the dynein-related genes were linked to an increased the risk of male infertility (OR = 21.52, 95% confidence interval 8.34-55.50, Z test = 6.35, p < 0.05). The percentage of heterogeneity, I , was 47.00%. The lack of variants in the dynein genes was an advantage, and this was statistically significant.
DISCUSSION
The results from the present review illustrate that pathogenic variants in genes both for dynein synthesis and for dynein assembly factors could be associated with isolated cases of male infertility without any other symptoms.
CONCLUSIONS
The genes addressed in this study, which are involved in both the production and assembly of dynein, could be used as molecular targets for future research into the etiology of sperm motility problems.
Topics: Dyneins; Humans; Infertility, Male; Male; Mutation; Sperm Motility; Spermatozoa
PubMed: 36057791
DOI: 10.1111/andr.13287 -
Neurobiology of Disease Jul 2020The cytoplasmic dynein motor complex transports essential signals and organelles from the cell periphery to the perinuclear region, hence is critical for the survival...
The cytoplasmic dynein motor complex transports essential signals and organelles from the cell periphery to the perinuclear region, hence is critical for the survival and function of highly polarized cells such as neurons. Dynein Light Chain Roadblock-Type 1 (DYNLRB1) is thought to be an accessory subunit required for specific cargos, but here we show that it is essential for general dynein-mediated transport and sensory neuron survival. Homozygous Dynlrb1 null mice are not viable and die during early embryonic development. Furthermore, heterozygous or adult knockdown animals display reduced neuronal growth, and selective depletion of Dynlrb1 in proprioceptive neurons compromises their survival. Conditional depletion of Dynlrb1 in sensory neurons causes deficits in several signaling pathways, including β-catenin subcellular localization, and a severe impairment in the axonal transport of both lysosomes and retrograde signaling endosomes. Hence, DYNLRB1 is an essential component of the dynein complex, and given dynein's critical functions in neuronal physiology, DYNLRB1 could have a prominent role in the etiology of human neurodegenerative diseases.
Topics: Animals; Axonal Transport; Carrier Proteins; Cell Survival; Cells, Cultured; Dyneins; Lysosomes; Male; Mice; Neurogenesis; Organelles; Sensory Receptor Cells; Transfection
PubMed: 32088381
DOI: 10.1016/j.nbd.2020.104816 -
The FEBS Journal Sep 2011After fusion with the cellular plasma membrane or endosomal membranes, viral particles are generally too large to diffuse freely within the crowded cytoplasm... (Review)
Review
After fusion with the cellular plasma membrane or endosomal membranes, viral particles are generally too large to diffuse freely within the crowded cytoplasm environment. Thus, they will never reach the cell nucleus or the perinuclear areas where replication or reverse transcription usually takes place. It has been proposed that many unrelated viruses are transported along microtubules in a retrograde manner using the cellular dynein machinery or, at least, some dynein components. A putative employment of the dynein motor in a dynein-mediated transport has been suggested from experiments in which viral capsid proteins were used as bait in yeast two-hybrid screens using libraries composed of cellular proteins and dynein-associated chains were retrieved as virus-interacting proteins. In most cases DYNLL1, DYNLT1 or DYNLRB1 were identified as the dynein chains that interact with viral proteins. The importance of these dynein-virus interactions has been supported, in principle, by the observation that in some cases the dynein-interacting motifs of viral proteins altered by site-directed mutagenesis result in non-infective virions. Furthermore, overexpression of p50 dynamitin, which blocks the dynein-dynactin interaction, or incubation of infected cells with peptides that compete with viral polypeptides for dynein binding have been shown to alter the viral retrograde transport. Still, it remains to be proved that dynein light chains can bind simultaneously to incoming virions and to the dynein motor for retrograde transport to take place. In this review, we will analyse the association of viral proteins with dynein polypeptides and its implications for viral infection.
Topics: Animals; Apoptosis; Biological Transport; Cytopathogenic Effect, Viral; Dyneins; Humans; Microtubules; Protein Interaction Domains and Motifs; Protein Subunits; Viral Proteins; Virus Physiological Phenomena
PubMed: 21777384
DOI: 10.1111/j.1742-4658.2011.08252.x -
Biochimica Et Biophysica Acta Mar 2000Dyneins are large multi-component microtubule-based molecular motors involved in many fundamental cellular processes including vesicular transport, mitosis and... (Review)
Review
Dyneins are large multi-component microtubule-based molecular motors involved in many fundamental cellular processes including vesicular transport, mitosis and ciliary/flagellar beating. In order to achieve useful work, these enzymes must contain motor, cargo-binding and regulatory components. The ATPase and microtubule motor domains are located within the very large dynein heavy chains that form the globular heads and stems of the complex. Cargo-binding activity involves the intermediate chains and several classes of light chain that associate in a subcomplex at the base of the soluble dynein particle. Regulatory control of dynein motor function is thought to involve the phosphorylation of various components as well as a series of light chain proteins that are directly associated with the heavy chains. These latter polypeptides have a variety of intriguing attributes, including redox-sensitive vicinal dithiols and Ca(2+)-binding, suggesting that the activity of individual dyneins may be subject to multiple regulatory inputs. Recent molecular, genetic and structural studies have revealed insight into the roles played by these various components and the mechanisms of dynein-based motility.
Topics: Animals; Dyneins; Meiosis; Models, Molecular; Molecular Motor Proteins; Multienzyme Complexes; Oxidation-Reduction; Phosphorylation; Protein Binding; Protein Conformation
PubMed: 10722877
DOI: 10.1016/s0167-4889(00)00009-4 -
Nature Structural & Molecular Biology Sep 2019Dynein-2 assembles with polymeric intraflagellar transport (IFT) trains to form a transport machinery that is crucial for cilia biogenesis and signaling. Here we...
Dynein-2 assembles with polymeric intraflagellar transport (IFT) trains to form a transport machinery that is crucial for cilia biogenesis and signaling. Here we recombinantly expressed the ~1.4-MDa human dynein-2 complex and solved its cryo-EM structure to near-atomic resolution. The two identical copies of the dynein-2 heavy chain are contorted into different conformations by a WDR60-WDR34 heterodimer and a block of two RB and six LC8 light chains. One heavy chain is steered into a zig-zag conformation, which matches the periodicity of the anterograde IFT-B train. Contacts between adjacent dyneins along the train indicate a cooperative mode of assembly. Removal of the WDR60-WDR34-light chain subcomplex renders dynein-2 monomeric and relieves autoinhibition of its motility. Our results converge on a model in which an unusual stoichiometry of non-motor subunits controls dynein-2 assembly, asymmetry, and activity, giving mechanistic insight into the interaction of dynein-2 with IFT trains and the origin of diverse functions in the dynein family.
Topics: Cryoelectron Microscopy; Dyneins; Humans; Protein Conformation; Protein Multimerization; Protein Transport
PubMed: 31451806
DOI: 10.1038/s41594-019-0286-y -
Journal of Biomedical Science Jun 2022In Neisseria meningitidis the HrpA/HrpB two-partner secretion system (TPS) was implicated in diverse functions including meningococcal competition, biofilm formation,...
BACKGROUND
In Neisseria meningitidis the HrpA/HrpB two-partner secretion system (TPS) was implicated in diverse functions including meningococcal competition, biofilm formation, adherence to epithelial cells, intracellular survival and vacuolar escape. These diverse functions could be attributed to distinct domains of secreted HrpA.
METHODS
A yeast two-hybrid screening, in vitro pull-down assay and immunofluorescence microscopy experiments were used to investigate the interaction between HrpA and the dynein light-chain, Tctex-type 1 (DYNLT1). In silico modeling was used to analyze HrpA structure. Western blot analysis was used to investigate apoptotic and pyroptotic markers.
RESULTS
The HrpA carboxy-terminal region acts as a manganese-dependent cell lysin, while the results of a yeast two-hybrid screening demonstrated that the HrpA middle region has the ability to bind the dynein light-chain, Tctex-type 1 (DYNLT1). This interaction was confirmed by in vitro pull-down assay and immunofluorescence microscopy experiments showing co-localization of N. meningitidis with DYNLT1 in infected epithelial cells. In silico modeling revealed that the HrpA-M interface interacting with the DYNLT1 has similarity with capsid proteins of neurotropic viruses that interact with the DYNLT1. Indeed, we found that HrpA plays a key role in infection of and meningococcal trafficking within neuronal cells, and is implicated in the modulation of the balance between apoptosis and pyroptosis.
CONCLUSIONS
Our findings revealed that N. meningitidis is able to effectively infect and survive in neuronal cells, and that this ability is dependent on HrpA, which establishes a direct protein-protein interaction with DYNLTI in these cells, suggesting that the HrpA interaction with dynein could be fundamental for N. meningitidis spreading inside the neurons. Moreover, we found that the balance between apoptotic and pyroptotic pathways is heavily affected by HrpA.
Topics: Dyneins; Epithelial Cells; Neisseria meningitidis; Pyroptosis; Saccharomyces cerevisiae
PubMed: 35765029
DOI: 10.1186/s12929-022-00829-8 -
The EMBO Journal Oct 2023The localization of RNAs in cells is critical for many cellular processes. Whereas motor-driven transport of ribonucleoprotein (RNP) condensates plays a prominent role...
The localization of RNAs in cells is critical for many cellular processes. Whereas motor-driven transport of ribonucleoprotein (RNP) condensates plays a prominent role in RNA localization in cells, their study remains limited by the scarcity of available tools allowing to manipulate condensates in a spatial manner. To fill this gap, we reconstitute in cellula a minimal RNP transport system based on bioengineered condensates, which were functionalized with kinesins and dynein-like motors, allowing for their positioning at either the cell periphery or centrosomes. This targeting mostly occurs through the active transport of the condensate scaffolds, which leads to localized nucleation of phase-separated condensates. Then, programming the condensates to recruit specific mRNAs is able to shift the localization of these mRNAs toward the cell periphery or the centrosomes. Our method opens novel perspectives for examining the role of RNA localization as a driver of cellular functions.
Topics: Microtubules; Ribonucleoproteins; RNA; RNA, Messenger; Dyneins
PubMed: 37724036
DOI: 10.15252/embj.2023114106 -
The FEBS Journal Sep 2011The LC8 family members of dynein light chains (DYNLL1 and DYNLL2 in vertebrates) are highly conserved ubiquitous eukaryotic homodimer proteins that interact, besides... (Review)
Review
The LC8 family members of dynein light chains (DYNLL1 and DYNLL2 in vertebrates) are highly conserved ubiquitous eukaryotic homodimer proteins that interact, besides dynein and myosin 5a motor proteins, with a large (and still incomplete) number of proteins involved in diverse biological functions. Despite an earlier suggestion that LC8 light chains function as cargo adapters of the above molecular motors, they are now recognized as regulatory hub proteins that interact with short linear motifs located in intrinsically disordered protein segments. The most prominent LC8 function is to promote dimerization of their binding partners that are often scaffold proteins of various complexes, including the intermediate chains of the dynein motor complex. Structural and functional aspects of this intriguing hub protein will be highlighted in this minireview.
Topics: Animals; Biological Transport; Cytoplasmic Dyneins; Cytoskeleton; Dyneins; Humans; Protein Interaction Domains and Motifs; Protein Subunits
PubMed: 21777386
DOI: 10.1111/j.1742-4658.2011.08254.x -
Cell Structure and Function Jul 1984