scholarly journals A Ras-like domain in the light intermediate chain bridges the dynein motor to a cargo-binding region

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Courtney M Schroeder ◽  
Jonathan ML Ostrem ◽  
Nicholas T Hertz ◽  
Ronald D Vale
Keyword(s):  
G Proteins ◽  
Heavy Chain ◽  
Structural Information ◽  
Cytoplasmic Dynein ◽  
Protein Fold ◽  
Binding Region ◽  
Aromatic Residues ◽  
Dynein Motor ◽  
Insight Into ◽  
Intermediate Chain

Cytoplasmic dynein, a microtubule-based motor protein, transports many intracellular cargos by means of its light intermediate chain (LIC). In this study, we have determined the crystal structure of the conserved LIC domain, which binds the motor heavy chain, from a thermophilic fungus. We show that the LIC has a Ras-like fold with insertions that distinguish it from Ras and other previously described G proteins. Despite having a G protein fold, the fungal LIC has lost its ability to bind nucleotide, while the human LIC1 binds GDP preferentially over GTP. We show that the LIC G domain binds the dynein heavy chain using a conserved patch of aromatic residues, whereas the less conserved C-terminal domain binds several Rab effectors involved in membrane transport. These studies provide the first structural information and insight into the evolutionary origin of the LIC as well as revealing how this critical subunit connects the dynein motor to cargo.

scholarly journals Cytoplasmic Dynein Light Intermediate Chain Is Required for Discrete Aspects of Mitosis in Caenorhabditis elegans

2001 ◽  
Vol 12 (10) ◽  
pp. 2921-2933 ◽  
Author(s):  
John H. Yoder ◽  
Min Han
Keyword(s):  
Caenorhabditis Elegans ◽  
Nucleotide Binding ◽  
Cytoplasmic Dynein ◽  
Meiotic Spindle ◽  
Phenotypic Characterization ◽  
Loss Of Function ◽  
Dynein Motor ◽  
Centrosome Separation ◽  
Transporter Family ◽  
Intermediate Chain

We describe phenotypic characterization of dli-1, the Caenorhabditis elegans homolog of cytoplasmic dynein light intermediate chain (LIC), a subunit of the cytoplasmic dynein motor complex. Animals homozygous for loss-of-function mutations indli-1 exhibit stochastic failed divisions in late larval cell lineages, resulting in zygotic sterility. dli-1 is required for dynein function during mitosis. Depletion of thedli-1 gene product through RNA-mediated gene interference (RNAi) reveals an early embryonic requirement. One-celldli-1(RNAi) embryos exhibit failed cell division attempts, resulting from a variety of mitotic defects. Specifically, pronuclear migration, centrosome separation, and centrosome association with the male pronuclear envelope are defective indli-1(RNAi) embryos. Meiotic spindle formation, however, is not affected in these embryos. DLI-1, like its vertebrate homologs, contains a putative nucleotide-binding domain similar to those found in the ATP-binding cassette transporter family of ATPases as well as other nucleotide-binding and -hydrolyzing proteins. Amino acid substitutions in a conserved lysine residue, known to be required for nucleotide binding, confers complete rescue in a dli-1mutant background, indicating this is not an essential domain for DLI-1 function.

scholarly journals The Gene for the Intermediate Chain Subunit of Cytoplasmic Dynein Is Essential in Drosophila

Genetics ◽  
2002 ◽  
Vol 162 (3) ◽  
pp. 1211-1220 ◽  
Author(s):  
Kristin L M Boylan ◽  
Thomas S Hays
Keyword(s):  
Intracellular Transport ◽  
De Novo ◽  
Cytoplasmic Dynein ◽  
Chain Gene ◽  
Temperature Sensitive ◽  
Wing Development ◽  
Dynein Motor ◽  
Dynein Intermediate Chain ◽  
Microtubule Motor ◽  
Intermediate Chain

Abstract The microtubule motor cytoplasmic dynein powers a variety of intracellular transport events that are essential for cellular and developmental processes. A current hypothesis is that the accessory subunits of the dynein complex are important for the specialization of cytoplasmic dynein function. In a genetic approach to understanding the range of dynein functions and the contribution of the different subunits to dynein motor function and regulation, we have identified mutations in the gene for the cytoplasmic dynein intermediate chain, Dic19C. We used a functional Dic transgene in a genetic screen to recover X-linked lethal mutations that require this transgene for viability. Three Dic mutations were identified and characterized. All three Dic alleles result in larval lethality, demonstrating that the intermediate chain serves an essential function in Drosophila. Like a deficiency that removes Dic19C, the Dic mutations dominantly enhance the rough eye phenotype of Glued1, a dominant mutation in the gene for the p150 subunit of the dynactin complex, a dynein activator. Additionally, we used complementation analysis to identify an existing mutation, shortwing (sw), as an allele of the dynein intermediate chain gene. Unlike the Dic alleles isolated de novo, shortwing is homozygous viable and exhibits recessive and temperature-sensitive defects in eye and wing development. These phenotypes are rescued by the wild-type Dic transgene, indicating that shortwing is a viable allele of the dynein intermediate chain gene and revealing a novel role for dynein function during wing development.

scholarly journals The Third P-loop Domain in Cytoplasmic Dynein Heavy Chain Is Essential for Dynein Motor Function and ATP-sensitive Microtubule Binding

2003 ◽  
Vol 14 (4) ◽  
pp. 1355-1365 ◽  
Author(s):  
Andre Silvanovich ◽  
Min-gang Li ◽  
Madeline Serr ◽  
Sarah Mische ◽  
Thomas S. Hays
Keyword(s):  
Heavy Chain ◽  
Mutational Analysis ◽  
Cytoplasmic Dynein ◽  
Sequence Comparisons ◽  
Microtubule Binding ◽  
Dynein Heavy Chain ◽  
Dynein Motor ◽  
Microtubule Binding Domain ◽  
Atp Binding And Hydrolysis ◽  
Loop Domains

Sequence comparisons and structural analyses show that the dynein heavy chain motor subunit is related to the AAA family of chaperone-like ATPases. The core structure of the dynein motor unit derives from the assembly of six AAA domains into a hexameric ring. In dynein, the first four AAA domains contain consensus nucleotide triphosphate-binding motifs, or P-loops. The recent structural models of dynein heavy chain have fostered the hypothesis that the energy derived from hydrolysis at P-loop 1 acts through adjacent P-loop domains to effect changes in the attachment state of the microtubule-binding domain. However, to date, the functional significance of the P-loop domains adjacent to the ATP hydrolytic site has not been demonstrated. Our results provide a mutational analysis of P-loop function within the first and third AAA domains of theDrosophila cytoplasmic dynein heavy chain. Here we report the first evidence that P-loop-3 function is essential for dynein function. Significantly, our results further show that P-loop-3 function is required for the ATP-induced release of the dynein complex from microtubules. Mutation of P-loop-3 blocks ATP-mediated release of dynein from microtubules, but does not appear to block ATP binding and hydrolysis at P-loop 1. Combined with the recent recognition that dynein belongs to the family of AAA ATPases, the observations support current models in which the multiple AAA domains of the dynein heavy chain interact to support the translocation of the dynein motor down the microtubule lattice.

scholarly journals The offloading model for dynein function

2005 ◽  
Vol 168 (2) ◽  
pp. 201-207 ◽  
Author(s):  
Wei-Lih Lee ◽  
Michelle A. Kaiser ◽  
John A. Cooper
Keyword(s):  
Heavy Chain ◽  
Mitotic Spindle ◽  
Cell Cortex ◽  
Cytoplasmic Microtubule ◽  
Functional Studies ◽  
Dynein Intermediate Chain ◽  
Bud Neck ◽  
Cytoplasmic Microtubules ◽  
Insight Into ◽  
Intermediate Chain

During mitosis in budding yeast, dynein moves the mitotic spindle into the mother-bud neck. We have proposed an offloading model to explain how dynein works. Dynein is targeted to the dynamic plus end of a cytoplasmic microtubule, offloads to the cortex, becomes anchored and activated, and then pulls on the microtubule. Here, we perform functional studies of dynein intermediate chain (IC) and light intermediate chain (LIC). IC/Pac11 and LIC/Dyn3 are both essential for dynein function, similar to the heavy chain (HC/Dyn1). IC and LIC are targeted to the distal plus ends of dynamic cytoplasmic microtubules, as is HC, and their targeting depends on HC. Targeting of HC to the plus end depends on IC, but not LIC. IC also localizes as stationary dots at the cell cortex, the presumed result of offloading in our model, as does HC, but not LIC. Localization of HC to cortical dots depends on both IC and LIC. Thus, the IC and LIC accessory chains have different but essential roles in dynein function, providing new insight into the offloading model.

scholarly journals Dynein Intermediate Chain Mediated Dynein–Dynactin Interaction Is Required for Interphase Microtubule Organization and Centrosome Replication and Separation inDictyostelium

1999 ◽  
Vol 147 (6) ◽  
pp. 1261-1274 ◽  
Author(s):  
Shuo Ma ◽  
Leda Triviños-Lagos ◽  
Ralph Gräf ◽  
Rex L. Chisholm
Keyword(s):  
Heavy Chain ◽  
Physiological Role ◽  
Cytoplasmic Dynein ◽  
Wild Type ◽  
Microtubule Organization ◽  
Dynein Intermediate Chain ◽  
Organizing Center ◽  
Intermediate Chain

Cytoplasmic dynein intermediate chain (IC) mediates dynein–dynactin interaction in vitro (Karki, S., and E.L. Holzbaur. 1995. J. Biol. Chem. 270:28806–28811; Vaughan, K.T., and R.B. Vallee. 1995. J. Cell Biol. 131:1507–1516). To investigate the physiological role of IC and dynein–dynactin interaction, we expressed IC truncations in wild-type Dictyostelium cells. ICΔC associated with dynactin but not with dynein heavy chain, whereas ICΔN truncations bound to dynein but bound dynactin poorly. Both mutations resulted in abnormal localization to the Golgi complex, confirming dynein function was disrupted. Striking disorganization of interphase microtubule (MT) networks was observed when mutant expression was induced. In a majority of cells, the MT networks collapsed into large bundles. We also observed cells with multiple cytoplasmic asters and MTs lacking an organizing center. These cells accumulated abnormal DNA content, suggesting a defect in mitosis. Striking defects in centrosome morphology were also observed in IC mutants, mostly larger than normal centrosomes. Ultrastructural analysis of centrosomes in IC mutants showed interphase accumulation of large centrosomes typical of prophase as well as unusually paired centrosomes, suggesting defects in centrosome replication and separation. These results suggest that dynactin-mediated cytoplasmic dynein function is required for the proper organization of interphase MT network as well as centrosome replication and separation in Dictyostelium.

scholarly journals Drosophila cytoplasmic dynein, a microtubule motor that is asymmetrically localized in the oocyte.

1994 ◽  
Vol 126 (6) ◽  
pp. 1475-1494 ◽  
Author(s):  
M Li ◽  
M McGrail ◽  
M Serr ◽  
T S Hays
Keyword(s):  
Heavy Chain ◽  
Maternal Effect ◽  
Nurse Cell ◽  
Cytoplasmic Dynein ◽  
Cdna Clones ◽  
Dynein Heavy Chain ◽  
Dynein Motor ◽  
Maternal Effect Gene ◽  
Microtubule Motor ◽  
Egg Chambers

The unidirectional movements of the microtubule-associated motors, dyneins, and kinesins, provide an important mechanism for the positioning of cellular organelles and molecules. An intriguing possibility is that this mechanism may underlie the directed transport and asymmetric positioning of morphogens that influence the development of multicellular embryos. In this report, we characterize the Drosophila gene, Dhc64C, that encodes a cytoplasmic dynein heavy chain polypeptide. The primary structure of the Drosophila cytoplasmic dynein heavy chain polypeptide has been determined by the isolation and sequence analysis of overlapping cDNA clones. Drosophila cytoplasmic dynein is highly similar in sequence and structure to cytoplasmic dynein isoforms reported for other organisms. The Dhc64C dynein transcript is differentially expressed during development with the highest levels being detected in the ovaries of adult females. Within the developing egg chambers of the ovary, the dynein gene is predominantly transcribed in the nurse cell complex. In contrast, the encoded dynein motor protein displays a striking accumulation in the single cell that will develop as the oocyte. The temporal and spatial pattern of dynein accumulation in the oocyte is remarkably similar to that of several maternal effect gene products that are essential for oocyte differentiation and axis specification. This distribution and its disruption by specific maternal effect mutations lends support to recent models suggesting that microtubule motors participate in the transport of these morphogens from the nurse cell cytoplasm to the oocyte.

scholarly journals Cryo-electron tomography reveals that dynactin recruits a team of dyneins for processive motility

2017 ◽  
Author(s):  
Danielle A. Grotjahn ◽  
Saikat Chowdhury ◽  
Yiru Xu ◽  
Richard J. McKenney ◽  
Trina A. Schroer ◽  
...  
Keyword(s):  
Structural Information ◽  
Electron Tomography ◽  
Force Production ◽  
Cytoplasmic Dynein ◽  
Dimensional Structure ◽  
Cellular Transport ◽  
3 Dimensional ◽  
Dynein Motor ◽  
Cryo Electron Tomography ◽  
Dynactin Complex

AbstractA key player in the intracellular trafficking network is cytoplasmic dynein, a protein complex that transports molecular cargo along microtubule tracks. It has been shown that vertebrate dynein’s movement becomes strikingly enhanced upon interacting with a cofactor named dynactin and one of several cargo-adapters, such as BicaudalD2. However, the mechanisms responsible for this increase in transport efficiency are not well understood, largely due to a lack of structural information. We used cryo-electron tomography to visualize the first 3-dimensional structure of the intact dynein-dynactin complex bound to microtubules. Our structure reveals that the dynactin-cargo-adapter complex recruits and binds to two dimeric cytoplasmic dyneins. Interestingly, the dynein motor organization closely resembles that of axonemal dynein, suggesting that cytoplasmic dynein and axonemal dyneins may utilize similar mechanisms to coordinate multiple motors. We propose that grouping dyneins onto a single dynactin scaffold promotes collective force production as well as unidirectional processive motility. These findings provide a structural platform that facilitates a deeper biochemical and biophysical understanding of dynein regulation and cellular transport.

scholarly journals Assembly and activation of dynein–dynactin by the cargo adaptor protein Hook3

2016 ◽  
Vol 214 (3) ◽  
pp. 309-318 ◽  
Author(s):  
Courtney M. Schroeder ◽  
Ronald D. Vale
Keyword(s):  
Crystal Structure ◽  
Crucial Role ◽  
Ternary Complex ◽  
Adaptor Protein ◽  
Cytoplasmic Dynein ◽  
Allosteric Activation ◽  
Structural Details ◽  
Dynactin Complex ◽  
Insight Into ◽  
Intermediate Chain

Metazoan cytoplasmic dynein moves processively along microtubules with the aid of dynactin and an adaptor protein that joins dynein and dynactin into a stable ternary complex. Here, we examined how Hook3, a cargo adaptor involved in Golgi and endosome transport, forms a motile dynein–dynactin complex. We show that the conserved Hook domain interacts directly with the dynein light intermediate chain 1 (LIC1). By solving the crystal structure of the Hook domain and using structure-based mutagenesis, we identify two conserved surface residues that are each critical for LIC1 binding. Hook proteins with mutations in these residues fail to form a stable dynein–dynactin complex, revealing a crucial role for LIC1 in this interaction. We also identify a region of Hook3 specifically required for an allosteric activation of processive motility. Our work reveals the structural details of Hook3’s interaction with dynein and offers insight into how cargo adaptors form processive dynein–dynactin motor complexes.

Sign in / Sign up

Export Citation Format

Share Document