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1.
Proc Natl Acad Sci U S A ; 113(43): E6610-E6619, 2016 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-27791032

RESUMO

Capping Protein (CP) plays a central role in the creation of the Arp2/3-generated branched actin networks comprising lamellipodia and pseudopodia by virtue of its ability to cap the actin filament barbed end, which promotes Arp2/3-dependent filament nucleation and optimal branching. The highly conserved protein V-1/Myotrophin binds CP tightly in vitro to render it incapable of binding the barbed end. Here we addressed the physiological significance of this CP antagonist in Dictyostelium, which expresses a V-1 homolog that we show is very similar biochemically to mouse V-1. Consistent with previous studies of CP knockdown, overexpression of V-1 in Dictyostelium reduced the size of pseudopodia and the cortical content of Arp2/3 and induced the formation of filopodia. Importantly, these effects scaled positively with the degree of V-1 overexpression and were not seen with a V-1 mutant that cannot bind CP. V-1 is present in molar excess over CP, suggesting that it suppresses CP activity in the cytoplasm at steady state. Consistently, cells devoid of V-1, like cells overexpressing CP described previously, exhibited a significant decrease in cellular F-actin content. Moreover, V-1-null cells exhibited pronounced defects in macropinocytosis and chemotactic aggregation that were rescued by V-1, but not by the V-1 mutant. Together, these observations demonstrate that V-1 exerts significant influence in vivo on major actin-based processes via its ability to sequester CP. Finally, we present evidence that V-1's ability to sequester CP is regulated by phosphorylation, suggesting that cells may manipulate the level of active CP to tune their "actin phenotype."


Assuntos
Proteínas de Capeamento de Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Dictyostelium/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Protozoários/genética , Pseudópodes/metabolismo , Proteínas de Capeamento de Actina/metabolismo , Proteína 2 Relacionada a Actina/genética , Proteína 2 Relacionada a Actina/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Proteína 3 Relacionada a Actina/genética , Proteína 3 Relacionada a Actina/metabolismo , Actinas/genética , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Quimiotaxia/genética , Sequência Conservada , Dictyostelium/genética , Dictyostelium/ultraestrutura , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Cinética , Camundongos , Mutação , Fosforilação , Pinocitose/genética , Ligação Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas de Protozoários/metabolismo , Pseudópodes/genética , Pseudópodes/ultraestrutura , Alinhamento de Sequência , Transdução de Sinais
2.
Science ; 346(6208): 1257998, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25342811

RESUMO

Although fluorescence microscopy provides a crucial window into the physiology of living specimens, many biological processes are too fragile, are too small, or occur too rapidly to see clearly with existing tools. We crafted ultrathin light sheets from two-dimensional optical lattices that allowed us to image three-dimensional (3D) dynamics for hundreds of volumes, often at subsecond intervals, at the diffraction limit and beyond. We applied this to systems spanning four orders of magnitude in space and time, including the diffusion of single transcription factor molecules in stem cell spheroids, the dynamic instability of mitotic microtubules, the immunological synapse, neutrophil motility in a 3D matrix, and embryogenesis in Caenorhabditis elegans and Drosophila melanogaster. The results provide a visceral reminder of the beauty and the complexity of living systems.


Assuntos
Caenorhabditis elegans/embriologia , Drosophila melanogaster/embriologia , Embrião não Mamífero/ultraestrutura , Imageamento Tridimensional/métodos , Microscopia/métodos , Imagem Molecular/métodos , Animais , Comunicação Celular , Células-Tronco Embrionárias/ultraestrutura , Camundongos , Esferoides Celulares/ultraestrutura
3.
Nat Med ; 19(10): 1281-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24056772

RESUMO

Endothelial secretion of von Willebrand factor (VWF) from intracellular organelles known as Weibel-Palade bodies (WPBs) is required for platelet adhesion to the injured vessel wall. Here we demonstrate that WPBs are often found near or within autophagosomes and that endothelial autophagosomes contain abundant VWF protein. Pharmacological inhibitors of autophagy or knockdown of the essential autophagy genes Atg5 or Atg7 inhibits the in vitro secretion of VWF. Furthermore, although mice with endothelial-specific deletion of Atg7 have normal vessel architecture and capillary density, they exhibit impaired epinephrine-stimulated VWF release, reduced levels of high-molecular weight VWF multimers and a corresponding prolongation of bleeding times. Endothelial-specific deletion of Atg5 or pharmacological inhibition of autophagic flux results in a similar in vivo alteration of hemostasis. Thus, autophagy regulates endothelial VWF secretion, and transient pharmacological inhibition of autophagic flux may be a useful strategy to prevent thrombotic events.


Assuntos
Autofagia , Células Endoteliais/metabolismo , Fator de von Willebrand/metabolismo , Proteína 5 Relacionada à Autofagia , Proteína 7 Relacionada à Autofagia , Exocitose , Hemostasia , Humanos , Proteínas Associadas aos Microtúbulos/genética , Enzimas Ativadoras de Ubiquitina/genética , Corpos de Weibel-Palade/metabolismo
4.
Biochem Biophys Res Commun ; 426(2): 209-14, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22940130

RESUMO

In mammals, pigments are made by melanocytes within a specialized organelle, the melanosome. Mature, pigment-laden melanosomes are then transferred to keratinocytes to drive the visible pigmentation of the animal's hair and skin. The dilute suppressor (dsu) locus encodes an extragenic suppressor of the pigmentation defect exhibited by mice lacking myosin Va (i.e. dilute mice). We recently showed that melanoregulin, the product of the dsu locus, functions as a negative regulator of a shedding mechanism that drives the intercellular transfer of melanosomes from the melanocyte to the keratinocyte. Here we address melanoregulin's localization within the melanocyte, as well as the molecular basis for its localization. First, we confirm and extend recently published results using exogenous, GFP-tagged melanoregulin by showing that endogenous melanoregulin also targets extensively to melanosomes. Second, using site-directed mutagenesis, metabolic labeling with H(3)-palmitate, and an inhibitor of palmitoylation in vivo, we show that the targeting of melanoregulin to the limiting membranes of melanosomes in melanocytes and lysosomes in CV1 cells depends critically on the palmitoylation of one or more of six closely-spaced cysteine residues located near melanoregulin's N-terminus. Finally, using Fluorescence Recovery after Photobleaching (FRAP), we show that melanoregulin-GFP exhibits little if any tendency to cycle in and out of the melanosome membrane. We conclude that multiple palmitoylation serves to stably anchor melanoregulin in the melanosome membrane.


Assuntos
Proteínas de Transporte/metabolismo , Lipoilação , Melanócitos/metabolismo , Melanossomas/metabolismo , Animais , Linhagem Celular , Membranas Intracelulares/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Estabilidade Proteica
5.
J Cell Biol ; 198(4): 545-60, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22908308

RESUMO

Rab proteins are important regulators of insulin-stimulated GLUT4 translocation to the plasma membrane (PM), but the precise steps in GLUT4 trafficking modulated by particular Rab proteins remain unclear. Here, we systematically investigate the involvement of Rab proteins in GLUT4 trafficking, focusing on Rab proteins directly mediating GLUT4 storage vesicle (GSV) delivery to the PM. Using dual-color total internal reflection fluorescence (TIRF) microscopy and an insulin-responsive aminopeptidase (IRAP)-pHluorin fusion assay, we demonstrated that Rab10 directly facilitated GSV translocation to and docking at the PM. Rab14 mediated GLUT4 delivery to the PM via endosomal compartments containing transferrin receptor (TfR), whereas Rab4A, Rab4B, and Rab8A recycled GLUT4 through the endosomal system. Myosin-Va associated with GSVs by interacting with Rab10, positioning peripherally recruited GSVs for ultimate fusion. Thus, multiple Rab proteins regulate the trafficking of GLUT4, with Rab10 coordinating with myosin-Va to mediate the final steps of insulin-stimulated GSV translocation to the PM.


Assuntos
Adipócitos/metabolismo , Vesículas Citoplasmáticas/fisiologia , Transportador de Glucose Tipo 4/metabolismo , Insulina/fisiologia , Cadeias Pesadas de Miosina/fisiologia , Miosina Tipo V/fisiologia , Proteínas rab de Ligação ao GTP/fisiologia , Células 3T3-L1 , Animais , Membrana Celular/metabolismo , Camundongos , Transporte Proteico/fisiologia
6.
Proc Natl Acad Sci U S A ; 109(31): E2101-9, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-22753477

RESUMO

Mammalian pigmentation is driven by the intercellular transfer of pigment-containing melanosomes from the tips of melanocyte dendrites to surrounding keratinocytes. Tip accumulation of melanosomes requires myosin Va, because melanosomes concentrate in the center of melanocytes from myosin Va-null (dilute) mice. This distribution defect results in inefficient melanosome transfer and a dilution of coat color. Dilute mice that simultaneously lack melanoregulin, the product of the dilute suppressor locus, exhibit a nearly complete restoration of coat color, but, surprisingly, melanosomes remain concentrated in the center of their melanocytes. Here we show that dilute/dsu melanocytes, but not dilute melanocytes, readily transfer the melanosomes concentrated in their center to surrounding keratinocytes in situ. Using time-lapse imaging of WT melanocyte/keratinocyte cocultures in which the plasma membranes of the two cells are marked with different colors, we define an intercellular melanosome transfer pathway that involves the shedding by the melanocyte of melanosome-rich packages, which subsequently are phagocytosed by the keratinocyte. Shedding, which occurs primarily at dendritic tips but also from more central regions, involves adhesion to the keratinocyte, thinning behind the forming package, and apparent self-abscission. Finally, we show that shedding from the cell center is sixfold more frequent in cultured dilute/dsu melanocytes than in dilute melanocytes, consistent with the in situ data. Together, these results explain how dsu restores the coat color of dilute mice without restoring intracellular melanosome distribution, indicate that melanoregulin is a negative regulator of melanosome transfer, and provide insight into the mechanism of intercellular melanosome transfer.


Assuntos
Proteínas de Transporte/metabolismo , Queratinócitos/metabolismo , Melanócitos/metabolismo , Melanossomas/metabolismo , Pigmentação da Pele/fisiologia , Animais , Transporte Biológico Ativo/fisiologia , Proteínas de Transporte/genética , Células Cultivadas , Técnicas de Cocultura , Peptídeos e Proteínas de Sinalização Intracelular , Queratinócitos/citologia , Melanócitos/citologia , Melanossomas/genética , Camundongos , Camundongos Mutantes , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo V/genética , Miosina Tipo V/metabolismo
7.
Mol Biol Cell ; 23(5): 834-52, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22219382

RESUMO

Actin retrograde flow and actomyosin II contraction have both been implicated in the inward movement of T cell receptor (TCR) microclusters and immunological synapse formation, but no study has integrated and quantified their relative contributions. Using Jurkat T cells expressing fluorescent myosin IIA heavy chain and F-tractin-a novel reporter for F-actin-we now provide direct evidence that the distal supramolecular activation cluster (dSMAC) and peripheral supramolecular activation cluster (pSMAC) correspond to lamellipodial (LP) and lamellar (LM) actin networks, respectively, as hypothesized previously. Our images reveal concentric and contracting actomyosin II arcs/rings at the LM/pSMAC. Moreover, the speeds of centripetally moving TCR microclusters correspond very closely to the rates of actin retrograde flow in the LP/dSMAC and actomyosin II arc contraction in the LM/pSMAC. Using cytochalasin D and jasplakinolide to selectively inhibit actin retrograde flow in the LP/dSMAC and blebbistatin to selectively inhibit actomyosin II arc contraction in the LM/pSMAC, we demonstrate that both forces are required for centripetal TCR microcluster transport. Finally, we show that leukocyte function-associated antigen 1 clusters accumulate over time at the inner aspect of the LM/pSMAC and that this accumulation depends on actomyosin II contraction. Thus actin retrograde flow and actomyosin II arc contraction coordinately drive receptor cluster dynamics at the immunological synapse.


Assuntos
Actinas/metabolismo , Actomiosina/metabolismo , Sinapses Imunológicas/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Citocalasina D/farmacologia , Depsipeptídeos/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Células Jurkat , Antígeno-1 Associado à Função Linfocitária/metabolismo , Miosina não Muscular Tipo IIA/metabolismo
8.
Biomed Opt Express ; 2(10): 2761-9, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22025982

RESUMO

Multi-modal nanoparticles incorporating fluorophores are increasingly being used for medical applications. The number of fluorophores incorporated into the nanoparticles during synthesis is stochastic, leaving some nanoparticles devoid of fluorophores. Determining the number, the brightness and the photostability of the fluorophores incorporated, and the percentage of labeled nanoparticles (labeling efficiency) remains challenging. We have determined the aforementioned quantities for two synthesized multi-modal nanoparticles by exploiting the photobleaching of fluorophores at the single-molecule level using a total internal reflection fluorescence microscope. Labeling efficiency was determined by fitting the distribution of incorporated fluorophores with a statistical model and verified by independent experiments.

9.
Cell Immunol ; 271(2): 267-79, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21843881

RESUMO

Here we imaged the exocytosis of lytic granules from human CD8(+) cytotoxic T lymphocytes using rapid total internal reflection microscopy, Lamp-1 tagged with mGFP to follow the fate of the lytic granule membrane, and granzyme A, granzyme B or serglycin tagged with mRFP to follow the fate of lytic granule cargo. Lytic granules were released by full fusion with the plasma membrane, such that the entire granule content for all three cargos visualized was released on a subsecond time scale. The behavior of GFP-Lamp-1 was, however, more complex. While it entered the plasma membrane in all cases, the extent to which it then diffused away from the site of exocytosis varied from nearly complete to highly restricted. Finally, the diffusion properties upon release of the three cargos examined put an upper limit on the size of the macromolecular complex of granzyme and serglycin that is presented to the target cell.


Assuntos
Exocitose/fisiologia , Fusão de Membrana/fisiologia , Linfócitos T Citotóxicos/fisiologia , Animais , Exocitose/imunologia , Granzimas/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Técnicas In Vitro , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Fusão de Membrana/imunologia , Camundongos , Microscopia de Fluorescência , Proteoglicanas/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Vesículas Secretórias/imunologia , Vesículas Secretórias/fisiologia , Linfócitos T Citotóxicos/imunologia , Proteínas de Transporte Vesicular/metabolismo
10.
Immunol Cell Biol ; 89(6): 728-38, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21483445

RESUMO

Lytic granules in cytotoxic lymphocytes, which include T cells and natural killer (NK) cells, are secretory lysosomes that release their content upon fusion with the plasma membrane (PM), a process known as degranulation. Although vesicle exocytosis has been extensively studied in endocrine and neuronal cells, much less is known about the fusion of lytic granules in cytotoxic lymphocytes. Here, we used total internal reflection fluorescence microscopy to examine lytic granules labeled with fluorescently tagged Fas ligand (FasL) in the NK cell line NKL stimulated with phorbol ester and ionomycin and in primary NK cells activated by physiological receptor-ligand interactions. Two fusion modes were observed: complete fusion, characterized by loss of granule content and rapid diffusion of FasL at the PM; and incomplete fusion, characterized by transient fusion pore opening and retention of FasL at the fusion site. The pH-sensitive green fluorescence protein (pHluorin) fused to the lumenal domain of FasL was used to visualize fusion pore opening with a time resolution of 30 ms. Upon incomplete fusion, pHluorin emission lasted several seconds in the absence of noticeable diffusion. Thus, we conclude that lytic granules in NK cells undergo both complete and incomplete fusion with the PM, and propose that incomplete fusion may promote efficient recycling of lytic granule membrane after the release of cytotoxic effector molecules.


Assuntos
Degranulação Celular/imunologia , Grânulos Citoplasmáticos/metabolismo , Células Matadoras Naturais/imunologia , Fusão de Membrana/fisiologia , Células Cultivadas , Proteína Ligante Fas/metabolismo , Humanos , Ativação Linfocitária/imunologia
11.
Curr Biol ; 17(23): R1017-9, 2007 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-18054764

RESUMO

The study of fish and amphibian melanocytes has yielded a wealth of information on the regulation of microtubule- and actin-based motor proteins involved in organelle transport. A new zebrafish mutant provides further insight into how the actions of these motors are coordinated in vivo.


Assuntos
Actinas/metabolismo , Melanossomas/fisiologia , Microtúbulos/metabolismo , Proteínas Motores Moleculares/metabolismo , Peixe-Zebra/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Melanócitos/fisiologia , Melanóforos/fisiologia , Melanossomas/metabolismo , Camundongos , Organelas/metabolismo , Organelas/fisiologia , Peixe-Zebra/genética
12.
J Cell Biol ; 171(2): 201-7, 2005 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-16247022

RESUMO

In mouse melanocytes, myosin Va is recruited onto the surface of melanosomes by a receptor complex containing Rab27a that is present in the melanosome membrane and melanophilin (Mlp), which links myosin Va to Rab27a. In this study, we show that Mlp is also a microtubule plus end-tracking protein or +TIP. Moreover, myosin Va tracks the plus end in a Mlp-dependent manner. Data showing that overexpression and short inhibitory RNA knockdown of the +TIP EB1 have opposite effects on Mlp-microtubule interaction, that Mlp interacts directly with EB1, and that deletion from Mlp of a region similar to one in the adenomatous polyposis coli protein involved in EB1 binding blocks Mlp's ability to plus end track argue that Mlp tracks the plus end indirectly [corrected] by hitchhiking on EB1. These results identify a novel +TIP and indicate that vertebrate cells possess a +TIP complex that is similar to the Myo2p-Kar9p-Bim1p complex in yeast. We suggest that the +TIP complex identified in this study may serve to focus the transfer of melanosomes from microtubules to actin at the microtubule plus end.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Miosina Tipo V/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Substâncias Macromoleculares/metabolismo , Melanócitos/metabolismo , Melanossomas/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Dados de Sequência Molecular , RNA Interferente Pequeno/metabolismo , Ratos , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab27 de Ligação ao GTP
13.
Proc Natl Acad Sci U S A ; 101(48): 16831-6, 2004 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-15550542

RESUMO

MYO5A is a major actin-based vesicle transport motor that binds to one of its cargos, the melanosome, by means of a RAB27A/MLPH receptor. When one of the members of this receptor-motor complex is mutated, the melanosomes clump in the perinuclear region of the melanocyte and are transferred unevenly to the developing hair, leading to a dilution of coat color. Mutation of a fourth gene, dilute suppressor (dsu), suppresses this coat color dilution. MYO5A is required for the peripheral accumulation of melanosomes in melanocytes, but its role in melanosome transfer to neighboring keratinocytes and the hair is unknown. Here, we show that MYO5A is nonessential for melanosome transfer, although pigment incorporation into the hair in MYO5A-deficient mice is uneven, probably due to the clumping of melanosomes that occurs in the perinuclear region of mutant melanocytes. We also show that dsu is caused by a loss-of-function mutation in a unique vertebrate-specific protein that appears to function in an MYO5A-independent pathway to alter pigment incorporation into the hair. Therefore, dsu identifies a unique protein involved in pigmentation of the mammalian hair.


Assuntos
Cor de Cabelo/genética , Cadeias Pesadas de Miosina/fisiologia , Miosina Tipo V/fisiologia , Animais , Western Blotting , Cromossomos Bacterianos , Teste de Complementação Genética , Camundongos , Dados de Sequência Molecular , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/genética
14.
Nat Cell Biol ; 4(4): 271-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11887186

RESUMO

Little is known about how molecular motors bind to their vesicular cargo. Here we show that myosin-Va, an actin-based vesicle motor, binds to one of its cargoes, the melanosome, by interacting with a receptor-protein complex containing Rab27a and melanophilin, a postulated Rab27a effector. Rab27a binds to the melanosome first and then recruits melanophilin, which in turn recruits myosin-Va. Melanophilin creates this link by binding to Rab27a in a GTP-dependent fashion through its amino terminus, and to myosin-Va through its carboxy terminus. Moreover, this latter interaction, similar to the ability of myosin-Va to colocalize with melanosomes and influence their distribution in vivo, is absolutely dependent on the presence of exon-F, an alternatively spliced exon in the myosin-Va tail. These results provide the first molecular description of an organelle receptor for an actin-based motor, illustrate how alternate exon usage can be used to specify cargo, and further expand the functional repertoire of Rab GTPases and their effectors.


Assuntos
Proteínas de Transporte/química , Miosina Tipo V/química , Miosina Tipo V/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Processamento Alternativo , Animais , Animais Recém-Nascidos , Proteínas de Transporte/metabolismo , Células Cultivadas , Éxons , Proteínas de Fluorescência Verde , Cinética , Proteínas Luminescentes/metabolismo , Melanócitos/metabolismo , Melanossomas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Modelos Genéticos , Fenótipo , Plasmídeos/metabolismo , Ligação Proteica , Isoformas de Proteínas , Estrutura Terciária de Proteína , Transfecção , Técnicas do Sistema de Duplo-Híbrido , Proteínas rab de Ligação ao GTP/química , Proteínas rab27 de Ligação ao GTP , Proteína rab3A de Ligação ao GTP/metabolismo
15.
Curr Opin Cell Biol ; 14(1): 69-75, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11792547

RESUMO

Rab GTPases and their effectors regulate membrane traffic by determining, along with cognate SNAREs, the specificity of transport vesicle docking and fusion steps. Recent studies have also implicated Rabs in the movement of these transport vesicles from their site of formation to their site of fusion, and several Rabs have been linked to specific microtubule- or actin-based motor proteins. Analyses of Rab and motor protein mutants, coupled with advanced imaging techniques, have led to the suggestion that certain Rabs function as essential components of the vesicle receptor for specific motor proteins.


Assuntos
Proteínas Motores Moleculares/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Citoesqueleto/metabolismo , Microtúbulos/metabolismo , Modelos Biológicos , Vesículas Transportadoras/metabolismo , Proteínas rab de Ligação ao GTP/fisiologia
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