1
|
Ravi S, Johnson MS, Chacko BK, Kramer PA, Sawada H, Locy ML, Wilson LS, Barnes S, Marques MB, Darley-Usmar VM. Modification of platelet proteins by 4-hydroxynonenal: Potential Mechanisms for inhibition of aggregation and metabolism. Free Radic Biol Med 2016; 91:143-53. [PMID: 26475426 PMCID: PMC4761519 DOI: 10.1016/j.freeradbiomed.2015.10.408] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/06/2015] [Accepted: 10/10/2015] [Indexed: 01/23/2023]
Abstract
Platelet aggregation is an essential response to tissue injury and is associated with activation of pro-oxidant enzymes, such as cyclooxygenase, and is also a highly energetic process. The two central energetic pathways in the cell, glycolysis and mitochondrial oxidative phosphorylation, are susceptible to damage by reactive lipid species. Interestingly, how platelet metabolism is affected by the oxidative stress associated with aggregation is largely unexplored. To address this issue, we examined the response of human platelets to 4-hydroxynonenal (4-HNE), a reactive lipid species which is generated during thrombus formation and during oxidative stress. Elevated plasma 4-HNE has been associated with renal failure, septic shock and cardiopulmonary bypass surgery. In this study, we found that 4-HNE decreased thrombin stimulated platelet aggregation by approximately 60%. The metabolomics analysis demonstrated that underlying our previous observation of a stimulation of platelet energetics by thrombin glycolysis and TCA (Tricarboxylic acid) metabolites were increased. Next, we assessed the effect of both 4-HNE and alkyne HNE (A-HNE) on bioenergetics and targeted metabolomics, and found a stimulatory effect on glycolysis, associated with inhibition of bioenergetic parameters. In the presence of HNE and thrombin glycolysis was further stimulated but the levels of the TCA metabolites were markedly suppressed. Identification of proteins modified by A-HNE followed by click chemistry and mass spectrometry revealed essential targets in platelet activation including proteins involved in metabolism, adhesion, cytoskeletal reorganization, aggregation, vesicular transport, protein folding, antioxidant proteins, and small GTPases. In summary, the biological effects of 4-HNE can be more effectively explained in platelets by the integrated effects of the modification of an electrophile responsive proteome rather than the isolated effects of candidate proteins.
Collapse
Affiliation(s)
- Saranya Ravi
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | - Michelle S Johnson
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | - Balu K Chacko
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | - Philip A Kramer
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | - Hirotaka Sawada
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | - Morgan L Locy
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology
| | | | - Stephen Barnes
- The Targeted Metabolomics and Proteomics Laboratory; Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Victor M Darley-Usmar
- Department of Pathology; UAB Mitochondrial Medicine Laboratory; Center for Free Radical Biology.
| |
Collapse
|
2
|
Albrecht RM, Goodman SL, Simmons SR. Distribution and movement of membrane-associated platelet glycoproteins: use of colloidal gold with correlative video-enhanced light microscopy, low-voltage high-resolution scanning electron microscopy, and high-voltage transmission electron microscopy. THE AMERICAN JOURNAL OF ANATOMY 1989; 185:149-64. [PMID: 2773810 DOI: 10.1002/aja.1001850208] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Scanning electron microscopy (SEM), especially low-voltage (1 KeV) high-resolution SEM, can be used in conjunction with stereo pair high-voltage (1 MeV) transmission electron microscopy (HVEM) of whole spread cells or thick sections effectively to correlate surface structure with internal structure. Surface features such as microvilli, pits, pseudopodia, ruffles, attached virus, and other surface-related morphologic characteristics can be identified using SEM, while underlying cytoskeletal structure and organelle organization can be viewed by HVEM of the same preparation. However, the need to "prepare" cells for electron microscopy precludes observation in the living state. The use of several types of video-enhanced light microscopy (VLM) permits observation of living cells such that certain surface and internal features can be observed at a relatively high level of resolution or detection. Thus, changes in living cells can be followed, and at appropriate times the cells may be chemically fixed or rapidly frozen and prepared for ultrastructural examination by electron microscopy. We have utilized VLM in conjunction with SEM and HVEM to correlate changes in shape and surface structure with changes in the internal structure of platelets. In addition, we have found it advantageous to use colloidal gold-labeling procedures, because these markers are detectable by all three forms of microscopy. Using this approach we have labeled platelet membrane GPIIb/IIIa, a receptor for RGD-containing adhesive proteins, with gold-fibrinogen or gold-anti-IIb/IIIa. The initial binding and subsequent movement of gold-fibrinogen-IIb/IIIa complexes in living platelets was followed by VLM. The movement of individual labels could be mapped. Subsequent observation by low-voltage (1 KeV) high-resolution SEM and HVEM permits visualization of the same individual receptors tracked by LM. The final position on the membrane or the position-in-transit when fixative was added was determined relative to surface ultrastructure (SEM) and internal, particularly cytoskeletal, ultrastructure (HVEM).
Collapse
Affiliation(s)
- R M Albrecht
- Department of Veterinary Science, University of Wisconsin, Madison 53706
| | | | | |
Collapse
|
3
|
Abstract
The formation of the hemostatic plug on areas of skin injury is characterized as a sequence of structure-forming processes ending in the formation of an impenetrable barrier. The morphology of this barrier is further elucidated by means of scanning- and transmission electron microscopy. Especially the fibrin coating of the injury shows a completely different formation than is deducible from the solely hemostaseologically orientated view of the formation of the hemostatic plug. These structure-forming processes are: activation of the intrinsic clotting system by means of explosion-like destruction of thrombocytes with an immediate formation of a fibrin clot within seconds after the injury. Later during the process the fibrin clot is then condensed and as a function of thrombocyte dependent retraction receives its final fibrin stabilisation and modellation towards an occluding plug. The very narrow net formation of fibrin fibers is interpreted as dependent on the destruction of thrombocyte pseudopodia using their round shape as a rail for fibrin fiber formation. Disturbances of clot formation of postmortal clots compared to vital clots are interpreted as functional thrombocytic distortions, especially of the thrombocytic energy metabolism. Extracorporal clotting of blood drops after extreme ischemia resemble fibrin structures and fibrin structure formation distortions of postmortal origin.
Collapse
|
4
|
Tanaka K, Shibata N, Okamoto K, Matsusaka T, Fukuda H, Takagi M, Fujii N, Toya N, Onji T. Reorganization of myosin in surface-activated spreading platelets. JOURNAL OF ULTRASTRUCTURE AND MOLECULAR STRUCTURE RESEARCH 1986; 97:165-86. [PMID: 3134496 DOI: 10.1016/s0889-1605(86)80016-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
To study the localization of myosin in platelets, we utilized polyclonal antibody to heavy chain of platelet myosin. Both immunofluorescence and indirect immunogold staining techniques were employed. (1) In the unactivated platelets, myosin was distributed homogeneously throughout the cytosol. The cytosolic myosin was removed after platelets were treated with Triton X-100. The association of myosin with actin microfilaments in unactivated platelets was minimal. (2) In the surface-activated platelets, myosin was unextractable by Triton X-100. The myosin antibody heavily decorated the actin cable-networks which characterized the activated platelets. (3) In the Triton-unextractable cytoskeleton of both unactivated and activated platelets, we found fine fibrils (about 1-nm wide) that were often associated with immunogolds. These fibrils were similar to purified myosin molecules observed in rotary-shadowed metal replicas and ultrathin sections. These results indicate that cytosolic myosin becomes associated with actin cable-networks after the activation of platelets.
Collapse
Affiliation(s)
- K Tanaka
- Research Institute, Center for Adult Diseases, Osaka, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Karlsson R, Lassing I, Höglund AS, Lindberg U. The organization of microfilaments in spreading platelets: a comparison with fibroblasts and glial cells. J Cell Physiol 1984; 121:96-113. [PMID: 6541224 DOI: 10.1002/jcp.1041210113] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Platelets respond to stimulatory agents in general by the formation of long spikelike surface projections built up of tightly bundled microfilaments. During contact stimulation this is followed by a second phase when thin membrane lamellae grow out between the projections. This behaviour resembles that seen for instance in fibroblasts and glial cells, sending out microspikes and lamellipodia as a step in their advancement over solid substrata. Conditions, designed earlier for the preservation and visualization of the fragile organization of microfilaments and microtubules in the peripheral, highly motile parts (leading lamellae) of such cells (Höglund et al. (1980) J. Musc. Res. Cell Motility, 1:127-146), were used here to produce high-resolution images of the ultrastructural organization of platelets spreading on a solid substratum. This revealed an unexpected arrangement of actin filaments running parallel to the advancing edge, and small tufts of microfilaments on the outside of this edge-bundle. Cytochalasin D caused a regression of the spikelike projections as well as of both types of structures in the advancing platelet lamella and led to the appearance of a dense filamentous mat in juxtaposition to the plasma membrane. Analysis of the actin pools using the DNAase inhibition assay showed that the dramatic reorganizations of actin seen during the two phases of contact stimulation was reflected in a shift in the G/F-actin ratio only during the early phase.
Collapse
|
6
|
Zilla P, Groscurth P, Rhyner K, von Felten A. Surface morphology of human platelets during in vitro aggregation. SCANDINAVIAN JOURNAL OF HAEMATOLOGY 1984; 33:440-7. [PMID: 6515327 DOI: 10.1111/j.1600-0609.1984.tb00722.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The alterations of surface morphology of human platelets during the course of the aggregometer tracing were studied by scanning electron microscopy (SEM). Prior to activation the platelet rich plasma was pre-incubated at 37 degrees C for at least 30 min in order to obtain a sufficient number of discoid platelets. Immediately following the addition of collagen or ADP platelets showed slender pseudopods which thereafter were replaced by bulbous protrusions. The decrease in percent light transmission (%T) in the aggregometer tracing was characterized in SEM by a significant enlargement of bulbous protrusions and by the transformation of platelet shape from disc to sphere. During the increase in %T platelets forming primary aggregates displayed spiny pseudopods at their surface indicating that, during in vitro aggregation induced by collagen or ADP, two generations of pseudopods are formed. Using a low dose of ADP, the return of aggregometer tracing to the base line was regularly accompanied by dissociation of primary aggregates, but platelets remained spheroid and displayed pseudopods for a long time. Our study indicates that the course of aggregometer tracing is closely associated to the surface morphology of platelets. Single morphological changes, however, are not reflected by the aggregometer method.
Collapse
|
7
|
Tanaka K, Onji T, Okamoto K, Matsusaka T, Taniguchi H, Shibata N. Reorganization of contractile elements in the platelet during clot retraction. JOURNAL OF ULTRASTRUCTURE RESEARCH 1984; 89:98-109. [PMID: 6400031 DOI: 10.1016/s0022-5320(84)80027-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Electron microscopic studies have been carried out on human platelets in the clot retraction. In the early stage of clot formation, platelets send out filopodia, in which thin filaments run longitudinally. The thin filaments are often observed to attach to the cell membrane where fibrin strands bind from the extracellular surface. In the later stage of clot formation, thick filaments become observable, mainly in the cell body of the platelets. These thick filaments are arranged to form an ordered array, and thin filaments run parallel to them. The thin filaments often attach to the end of the thick filaments. However, thin filaments are not seen between the arrays of thick filaments. Similar structures are also observed in the cytoskeleton of the contracted platelet. These filaments closely resemble the purified myosin aggregates formed under low ionic strength. Thus, during clot retraction, both actin and myosin in platelets are reorganized into thin and thick filaments, respectively.
Collapse
|
8
|
|
9
|
|
10
|
Lewis JC, White MS, Prater T, Porter KR, Steele RJ. Three-dimensional organization of the platelet cytoskeleton during adhesion in vitro: observations on human and nonhuman primate cells. CELL MOTILITY 1983; 3:589-608. [PMID: 6686494 DOI: 10.1002/cm.970030525] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Adhesion of platelets in vitro resulted in rapid polymerization of the amorphous cytoplasmic ground substance into an organized cytoskeletal superstructure. This cytoskeleton, characterized through the use of whole-mount and stereo (3-D), high-voltage microscopy in conjunction with morphometrics and cytochemistry, comprised four major size classes of filaments organized in distinctive zones. The central matrix, or granulomere, at the center of the cell mass, was an ill-defined meshwork of 80-100-A filaments which enshrouded granules, dense bodies, and elements of the dense tubular system as identified through peroxidase cytochemistry. Demarcating this central matrix was a trabecular zone containing 30-50, 80-100, and 150-170 A filaments in an open and rigid-appearing lattice. Circumscribing the trabecular zone and extending to the margins of the hyalomere was the third region, the peripheral web, in which 70-A filaments were arranged in a tight honeycomb lattice. This organizational pattern was retained in cytoskeletons prepared by Triton x-100 extraction of the adherent cells, and was observed in basally located cells of aggregates which formed subsequent to adhesion. Our observations are consistent with biochemical studies of cytoskeletons prepared from suspended platelets and suggest a contractile protein composition for the superstructure during adhesion.
Collapse
|
11
|
Mürer EH, Stewart GJ, Davenport K, Siojo E, Rahwan RG, Witiak DT. Effect of three calcium antagonists on platelet secretion and metabolism. Biochem Pharmacol 1981; 30:523-30. [PMID: 7225147 DOI: 10.1016/0006-2952(81)90639-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
12
|
van Deurs B, Behnke O. Membrane structure of nonactivated and activated human blood platelets as revealed by freeze-fracture: evidence for particle redistribution during platelet contraction. J Cell Biol 1980; 87:209-18. [PMID: 7191427 PMCID: PMC2110721 DOI: 10.1083/jcb.87.1.209] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The distribution of intramembrane particles of nonactivated and activated human blood platelets was studied by freeze-fracture under various experimental conditions to see whether morphological evidence for a structural coupling between the platelet actomyosin system and the fibrin network in a retracting clot could be established. Membrane particles were evenly distributed in nonactivated platelets; the total number (E + P faces) was approximately 1,500/micrometers 2 of membrane, and there were two to three times more particles present on the E face than on the P face. Transformation of discoid platelets to "spiny spheres" by cooling did not change the particle distribution. Platelet activation and aggregation by serum or ADP caused no change in membrane particle density or distribution. Particle distribution was not changed in Ca2+-activated platelets fixed immediately before fibrin formation, but after fibrin formation and during clot retraction, particles were sometimes most frequent on the P face and tended to form distinct clusters, and aggregates of E face pits were observed. Blood platelets contain contractile proteins that are distinct as filaments in platelets in retracting clots. We suggest that the redistribution of particles seen in activated platelets during clot retraction reflects the esablishment of mechanical transmembrane links between the platelet actomyosin system and the fibrin net. The P-face particle clusters may represent sites of force transmission between actin filaments bonded to the inside of the membrane and the fibrin network at the outside. Thus, whereas membrane particles may not be directly involved in the attachment of actin filaments to membranes, the transmission of the force of the contractile system to an exterior substrate apparently involves the intramembrane particles.
Collapse
|
13
|
Abstract
The fine structure of resting and activated platelets was compared using two approaches novel to this dense cytoplasm. First, rapid lysis of platelets on carbon-coated grids was following by negative staining of the "cytoskeleton." Second, a brief, minimal fixation of platelets in plasma was coupled with partial lysis and examination of the unstained whole mounts at 200 kV. The results showed that the dense ground cytoplasm of discoid, fully resting platelets appeared granular or amorphous, and microfilaments were not observed. A coiled microtubule terminated in one, free, straight end. When any slight degree of activation occurred, microfilaments could be detected in the platelets. In fully spread specimens, the amorphous character of the resting cytoplasm was strikingly altered into an interconnected network of microfilaments. Stereo views of the whole mounts showed that dense granules, 100-250 nm in diameter, appeared as if suspended in the filament nets. The results support the view that platelet activation involves a major assembly of microfilaments from amorphous precursors. The change can only be seen convincingly when stringent precautions are taken during preparation because the platelets are very easily activated by thermal or mechanical stimuli.
Collapse
|
14
|
Morgenstern E. Ultracytochemistry of human blood platelets. PROGRESS IN HISTOCHEMISTRY AND CYTOCHEMISTRY 1980; 12:1-82. [PMID: 6987714 DOI: 10.1016/s0079-6336(80)80006-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
15
|
Allen RD, Zacharski LR, Widirstky ST, Rosenstein R, Zaitlin LM, Burgess DR. Transformation and motility of human platelets: details of the shape change and release reaction observed by optical and electron microscopy. J Cell Biol 1979; 83:126-42. [PMID: 511936 PMCID: PMC2110449 DOI: 10.1083/jcb.83.1.126] [Citation(s) in RCA: 166] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Blood platelets from 10 normal human subjects have been examined with a sensitive differential interference contrast (DIC) microscope. The entire transformation process during adhesion to glass is clearly visible and has been recorded cinematographically, including the disk to sphere change of shape, the formation of sessile protuberances, the extension and retraction of pseudopodia, and the spreading, ruffling, and occasional regression of the hyalomere. The exocytosis of intact dense bodies can be observed either by DIC microscopy, or by epifluorescence microscopy in platelets stained with mepacrine. Details of fluorescent flashes indicate that the dense bodies usually release their contents extracellularly, may do so intracytoplasmically under the influence of strong, short wavelength light on some preparations of mepacrine-stained platelets. The release of one or more dense bodies leaves a crater of variable size on the upper surface of the granulomere. Such craters represent the surface component of the open canalicular system and their formation and disappearance can be directly observed. Because these techniques permit quantitation of several parameters of motility which are not readily observable by other techniques, it is suggested that high extinction DIC microscope examination may become a rapid and useful method of studying congenital and acquired platelet disorders. Many features of platelet transformation have been confirmed and extended by scanning electron micrographs. These can in turn be interpreted by reference to time-lapse films of living platelets.
Collapse
|
16
|
Abstract
This article summarizes recent ultrastructure findings from our laboratory and documents some of the information accumulated primarily since 1975 from many laboratories. Special attention is given to documentation by scanning electron microscopy which affords insight into platelet activation (adhesion, aggregation, release/secretion) and especially platelet-vessel wall interactions. Structural physiology of platelets is considered in some detail as a basis for understanding platelet disorders contributing to clinical problems of thrombosis and hemorrhage. The impaired ability of von Willebrand platelets to adhere to injured vessel wall is reported using the human umbilical vein perfusion model. Relationships between platelets and blood coagulation factors focus on the exquisite sensitivity of platelets to minute amounts of thrombin. Unmasking of platelet factor 3 sites is identified on activated platelets, after glutaraldehyde fixation, by their reaction ot latex bearing anti-platelet factor 3 markers. The basis for platelet-collagen interactions is reviewed. Conditions for and possible mechanisms behind platelet interaction with vessel wall are discussed. Ex vivo flowing blood-vessel wall models offer opportunities for improved understanding of the platelets role(s) in vascular diseases.
Collapse
|
17
|
|
18
|
Abstract
Addition of ATP, CaCl2, and KCl to supernatants prepared from mycelia of Snowflake (strain 507), a morphological mutant of Neurospora crassa, results in the formation of filaments 70 nm in diameter. The "decorated" appearance of these filaments after incubation with heavy meromyosin from rabbits suggests they are actin-like.
Collapse
|
19
|
Zucker-Franklin D, Drosenberg L. Platelet interaction with modified articular cartilage. Its possible relevance to joint repair. J Clin Invest 1977; 59:641-51. [PMID: 557500 PMCID: PMC372268 DOI: 10.1172/jci108682] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
During studies concerned with the platelet-collagen interaction, it was observed that platelets did not adhere to bovine or human articular cartilage and that cartilage did not induce platelet aggregation in vivo or in vitro. To study the mechanism responsible for this observation, the role of proteoglycans was examined. Purified cartilage collagen proved to be fully active as a platelet aggregant. Addition of small amounts of proteoglycan subunit (PGS) blocked platelet aggregation, whereas chondroitin sulfate, a major glycosaminoglycan component of cartilage matrix, impaired platelet aggregation only at concentrations which resulted in a marked increase in viscosity. Moreover, PGS abolished aggregation of platelets by polylysine but did not prevent aggregation by ADP, suggesting that PGS may block strategically placed lysine sites on the collagen molecule. Treatment of fresh articular cartilage with proteolytic enzymes rendered the tissue active as a platelet aggregant. In vivo experiments demonstrated that surgical scarification of rabbit articular cartilage does not result in adhesion of autologous platelets. Treatment of rabbit knee joints with intraarticular trypsin 1 wk before the injection of blood resulted in adhesion and aggregation of platelets on the surface of the lesions. Since there is evidence from other studies that some degree of cartilage healing may take place after initiation of an inflammatory response, it is postulated that induction of platelet-cartilage interaction may eventuate in cartilage repair.
Collapse
|
20
|
|
21
|
Toyama Y. Actin-like filaments in the Sertoli cell junctional specializations in the swine and mouse testis. Anat Rec (Hoboken) 1976; 186:477-91. [PMID: 795323 DOI: 10.1002/ar.1091860403] [Citation(s) in RCA: 78] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Microfilaments at the junctional specializations between adjacent Sertoli cells and between the Sertoli cell and the late spermatid of the mouse and swine testes bind HMM and form arrowhead complexes with a periodicity of about 35 nm. The arrowhead formation is inhibited when the tissues are treated with HMM in the presence of ATP. These observations show that the microfilaments are actin-like in nature. The functional significance of these filaments in the Sertoli cell is discussed.
Collapse
|
22
|
Abstract
The association of actin filaments with membranes is an important feature in the motility of nonmuscle cells. We investigated the role of membrane particles in the attachment of actin filaments to membranes in those systems in which the attachment site can be identified. Freeze fractures through the end-on attachment site of the acrosomal filament bundles in Mytilus (mussel) and Limulus (horseshoe crab) sperm and the attachment site of the microvillar filament bundles in the brush border of intestinal epithelial cells were examined. There are no particles on the P face of the membrane at these sites in the sperm systems and generally none at these sites in microvilli. In microvilli, the actin filaments are also attached along their lengths to the membrane by bridges. When the isolated brush border is incubated in high concentrations of Mg++ (15 mM), the actin filaments form paracrystals and, as a result, the bridges are in register (330 A period). Under these conditions, alignment of the particles on the P face of the membrane into circumferential bands also occurs. However, these bands are generally separated by 800-900 A, indicating that all the bridges cannot be directly attached to membrane particles. Thus membrane particles are not directly involved in the attachment of actin filaments to membranes.
Collapse
|
23
|
Mooseker MS. Brush border motility. Microvillar contraction in triton-treated brush borders isolated from intestinal epithelium. J Cell Biol 1976; 71:417-33. [PMID: 11222 PMCID: PMC2109748 DOI: 10.1083/jcb.71.2.417] [Citation(s) in RCA: 126] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The brush border of intestinal epithelial cells consists of an array of tightly packed microvilli. Within each microvillus is a bundle of 20-30 actin filaments. The basal ends of the filament bundles are embedded in and interconected by a filamentous meshwork, the terminal web, which lies directly beneath the microvilli. When calcium and ATP are added to isolated brush borders that have been treated with the detergent, Triton X-100, the microvillar filament bundles rapidly retract into and through the terminal web region. Biochemical studies of brush border contractile proteins suggest that the observed microvillar contraction is actomyosin mediated. We have shown previously that the major protein of the brush border's actin (Tilney, L. G., and M. S. Mooseker. 1971. Proc. Natl. Acad. Sci. U. S. A. 68:2611-2615). The brush border also contains a protein with the same molecular weight as the heavy chain subunit of myosin (200, 000 daltons). In addition, preparations of demembranated brush borders exhibit potassium-EDTA ATPase activity of 0.02 mumol phosphate/mg-min (22 degrees C); this assay is diagnostic for myosin-like ATPase isolated from vertebrate sources. Other proteins of the brush border include a 30,000 dalton protein with properties similar to those of tropomyosin, and a protein with the same molecular weight as the Z band protein, alpha-actinin (95,000 daltons). How these observations bear on the basis for microvillar movements in vivo is discussed within the framework of our recent model for the organization of actin and myosin in the brush border (Mooseker, M. S., and L. G. Tilney. 1975. J. Cell Biol. 67:725-743).
Collapse
|
24
|
Lazarides E. Two general classes of cytoplasmic actin filaments in tissue culture cells: the role of tropomyosin. JOURNAL OF SUPRAMOLECULAR STRUCTURE 1976; 5:531(383)-563(415). [PMID: 800620 DOI: 10.1002/jss.400050410] [Citation(s) in RCA: 140] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
25
|
Mooseker MS, Tilney LG. Organization of an actin filament-membrane complex. Filament polarity and membrane attachment in the microvilli of intestinal epithelial cells. J Cell Biol 1975; 67:725-43. [PMID: 1202021 PMCID: PMC2111646 DOI: 10.1083/jcb.67.3.725] [Citation(s) in RCA: 451] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The association of actin filaments with membranes is now recognized as an important parameter in the motility of nonmuscle cells. We have investigated the organization of one of the most extensive and highly ordered actin filament-membrane complexes in nature, the brush border of intestinal epithelial cells. Through the analysis of isolated, demembranated brush borders decorated with the myosin subfragment, S1, we have determined that all the microvillar actin filaments have the same polarity. The S1 arrowhead complexes point away from the site of attachment of actin filaments at the apical tip of the microvillar membrane. In addition to the end-on attachment of actin filaments at the tip of the microvillus, these filaments are also connected to the plasma membrane all along their lengths by periodic (33 nm) cross bridges. These bridges were best observed in isolated brush borders incubated in high concentrations of Mg++. Their visibility is attributed to the induction of actin paracrystals in the filament bundles of the microvilli. Finally, we present evidence for the presence of myosinlike filaments in the terminal web region of the brush border. A model for the functional organization of actin and myosin in the brush border is presented.
Collapse
|
26
|
Schenk P. Microfilaments in human epithelial cancer cells. ZEITSCHRIFT FUR KREBSFORSCHUNG UND KLINISCHE ONKOLOGIE. CANCER RESEARCH AND CLINICAL ONCOLOGY 1975; 84:241-56. [PMID: 173103 DOI: 10.1007/bf00312246] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The occurence, distribution, and ultrastructural morphology of microfilaments in malignant epithelial cells of invasive squamous cell carcinoma of human oral cavity were studied by electron microscopy. The findings are compared with those in malignant oral epithelial cells of carcinoma-in-situ. In the malignant cells of invasive carcinoma, microfilaments 50-70 A in diameter are prominent in the cortical cytoplasm of the lateral and basal cell surfaces, adjacent and parallel to the plasma membrane, and extending into cell processes and microvillous extensions. Additional microfilaments are found to run from the peripheral cytoplasm to the perinuclear region. The microfilaments are aggregated into bundles aligned parallel to the long axis of the cell and display foci of increased electron density. They also tend to be aggregated into complex polygonal arrays. These microfilaments are similar in organization, concentration and ultrastructural architecture to those of various other nonmuscle cells, where they are thought to be capable of contraction and associated with cell motility. The presence of a microfilament system believed to be associated with contractile and motile cell processes may be an important characteristic of malignant cells of invasive tumors. The lack of abundant organized microfilaments in malignant cells in the absence of tumor invasion, and the presence of a prominent microfilament system in cells of invasive tumors, suggest that the microfilaments are related to the invasive properties of malignant tumor cells.
Collapse
|
27
|
Pollard TD. Electron microscopy of synthetic myosin filaments. Evidence for cross-bridge. Flexibility and copolymer formation. J Cell Biol 1975; 67:93-104. [PMID: 1236853 PMCID: PMC2109586 DOI: 10.1083/jcb.67.1.93] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Electron micrographs of negatively stained synthetic myosin filaments reveal that surface projections, believed to be the heads of the constituent myosin molecules, can exist in two configurations. Some filaments have the projections disposed close to the filament backbone. Other filaments have all of their projections widely spread, tethered to the backbone by slender threads. Filaments formed from the myosins of skeletal muscle, smooth muscle, and platelets each have distinctive features, particularly their lengths. Soluble mixtures of skeletal muscle myosin with either smooth muscle myosin or platelet myosin were dialyzed against 0.1 M KC1 at pH 7 to determine whether the simultaneous presence of two types of myosin would influence the properties of the filaments formed. In every case, a single population of filaments formed from the mixtures. The resulting filaments are thought to be copolymers of the two types of myosin, for several reasons: (a) their length-frequency distribution is unimodal and differs from that predicted for a simple mixture of two types of myosin filaments; (b) their mean length is intermediate between the mean lengths of the filaments formed separately from the two myosins in the mixture; (c) each of the filaments has structural features characteristic of both of the myosins in the mixture; and (d) their size and shape are determined by the proportion of the two myosins in the mixture.
Collapse
|
28
|
Niederman R, Pollard TD. Human platelet myosin. II. In vitro assembly and structure of myosin filaments. J Cell Biol 1975; 67:72-92. [PMID: 240861 PMCID: PMC2109578 DOI: 10.1083/jcb.67.1.72] [Citation(s) in RCA: 203] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We have used electron microscopy and solubility measurements to investigate the assembly and structure of purified human platelet myosin and myosin rod into filaments. In buffers with ionic strengths of less than 0.3 M, platelet myosin forms filaments which are remarkable for their small size, being only 320 nm long and 10-11 nm wide in the center of the bare zone. The dimensions of these filaments are not affected greatly by variation of the pH between 7 and 8, variation of the ionic strength between 0.05 and 0.2 M, the presence or absence of 1 mM Mg++ or ATP, or variation of the myosin concentration between 0.05 and 0.7 mg/ml. In 1 mM Ca++ and at pH 6.5 the filaments grow slightly larger. More than 90% of purified platelet myosin molecules assemble into filaments in 0.1 M KC1 at pH 7. Purified preparations of the tail fragment of platelet myosin also form filaments. These filaments are slightly larger than myosin filaments formed under the same conditions, indicating that the size of the myosin filaments may be influenced by some interaction between the head and tail portions of myosin molecules. Calculations based on the size and shape of the myosin filaments, the dimensions of the myosin molecule and analysis of the bare zone reveal that the synthetic platelet myosin filaments consists of 28 myosin molecules arranged in a bipolar array with the heads of two myosin molecules projecting from the backbone of the filament at 14-15 nm intervals. The heads appear to be loosely attached to the backbone by a flexible portion of the myosin tail. Given the concentration of myosin in platelets and the number of myosin molecules per filament, very few of these thin myosin filaments should be present in a thin section of a platelet, even if all of the myosin molecules are aggregated into filaments.
Collapse
|
29
|
|
30
|
Haverberg LN, Omstedt PT, Munro HN, Young VR. Ntau-methylhistidine content of mixed proteins in various rat tissues. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 405:67-71. [PMID: 1174569 DOI: 10.1016/0005-2795(75)90315-3] [Citation(s) in RCA: 89] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In order to use Ntau-methylhistidine (3-methylhistidine) excretion in the urine as a measure of muscle protein breakdown, it is necessary to demonstrate that other tissues are not important sources of this protein constituent. Accordingly, the concentration of Ntau-methylhistidine in blood serum and in the mixed proteins of heart, brain, lung, kidney, diaphragm, spleen, testis, stomach, liver and hind leg skeletal muscle was measured in male rats of approx. 400 g body weight. The free Ntau-methylhistidine concentration of rat serum was less than 2 nmol per ml. In contrast, measurable amounts of Ntau-methylhistidine were found in the mixed proteins of all tissues and organs examined. The highest concentration was found in skeletal muscle (658 nmol/g tissue). Assuming muscle mass to be 45% of body weight, it has been estimated that the muscle contains more than ten times the total amount of this amino acid present in all of the other organs analyzed, which together account for about 20% of total body weight. These findings indicate that skeletal muscle is likely to be the major source of urinary Ntau-methylhistidine and the latter is, in consequence, a reflection of myofibrillar protein breakdown in skeletal muscle.
Collapse
|
31
|
Owaribe K, Hatano S. Inducation of antibody against actin from myxomycete plasmodium and its properties. Biochemistry 1975; 14:3024-9. [PMID: 807241 DOI: 10.1021/bi00684a035] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Plasmodium actin was highly purified by gel filtration of crude G-actin on Sephadex G-100 followed by ultracentrifugation after polymerization in the presence of 1 M urea and 1 mM ATP. Purified actin showed a single band in the sodium dodecyl sulfate gel electrophoretic pattern. Antibody against this purified actin was induced in rabbits. The antibody obtained was immunologically monospecific for plasmodium actin, judging from the following results. (1) The addition of the antibody to a plasmodium F-action solution increased the turbidity of the mixed solution, showing the formation of the antibody-action complex. (2) In immunodiffusion and immunoelectrophoresis, the antibody formed single preciptin lines with the purified actin preparation and with the crude actin extract from the acetone-dried powder of plasmodium. (3) The antibody inhibited polymerization of plasmodium G-actin. (4) Plasmodium F-actin filaments were decorated with antibody in electron micrographs. The antibody reacted not only with plasmodium F- and G-actin, but also reacted with sea urchin egg actin, but it did not react with actin from rabbit striated muscle.
Collapse
|
32
|
Maron BJ, Ferrans VJ, Roberts WC. Ultrastructural features of degenerated cardiac muscle cells in patients with cardiac hypertrophy. THE AMERICAN JOURNAL OF PATHOLOGY 1975; 79:387-434. [PMID: 124533 PMCID: PMC1912738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Degenerated cardiac muscle cells were present in hypertrophied ventricular muscle obtained at operation from 12 (38%) of 32 patients with asymmetric septal hypertrophy (hypertrophic cardiomyopathy) or aortic valvular disease. Degenerated cells demonstrated a wide variety of ultrastructural alterations. Mildly altered cells were normal-sized or hypertrophied and showed focal changes, including preferential loss of thick (myosin) filaments, streaming and clumping of Z band material, and proliferation of the tubules of sarcoplasmic reticulum. Moderately and severely degenerated cells were normal-sized or atrophic and showed additional changes, including extensive myofibrillar lysis and loss of T tubules. The appearance of the most severely degenerated cells usually reflected the cytoplasmic organelle (sarcoplasmic reticulum, glycogen, or mitochondria) which underwent proliferation and filled the myofibril-free areas of these cells. Moderately and severely degenerated cells were present in areas of fibrosis, had thickened basement membranes, and had lost their intercellular connections. These observations suggest that degenerated cardiac muscle cells have poor contractile function and may be responsible for impaired cardiac performance in some patients with chronic ventricular hypertrophy.
Collapse
|
33
|
Abramowitz JW, Stracher A, Detwiler TC. A second form of actin: platelet microfilaments depolymerized by ATP and divalent cations. Arch Biochem Biophys 1975; 167:230-7. [PMID: 1130793 DOI: 10.1016/0003-9861(75)90459-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
34
|
Miranda AF, Godman GC, Tanenbaum SW. Action of cytochalasin D on cells of established lines. II. Cortex and microfilaments. J Cell Biol 1974; 62:406-23. [PMID: 4214822 PMCID: PMC2109385 DOI: 10.1083/jcb.62.2.406] [Citation(s) in RCA: 126] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cells in culture exposed to cytochalasin D (CD) rapidly undergo a long-sustained tonic contraction. Coincident with this contracture the thin microfilaments of the cortex become compacted into feltlike masses. The ravelled filaments of these masses remain actinlike and bind heavy meromyosin; they are not disrupted or disaggregated, but rather, appear to represent a contracted state of the microfilament apparatus of the cell cortex. On continued exposure to CD, 'myoid' bundles, containing thick, dense filaments, and larger fusiform or ribbonlike, putatively myosinoid, aggregates may appear. These appearances are interpreted as consequences of a state of hypercontraction without relaxation induced by CD. They do not occur in CD-treated cells prevented from contracting by inhibitors of energy metabolism, and are readily reversible on withdrawal of CD. Extensive ordered arrays of thin microfilaments develop in cells which are reextending during early recovery.
Collapse
|
35
|
Zucker MB, Troll W, Belman S. The tumor-promoter phorbol ester (12-O-tetradecanoyl-phorbol-13-acetate), a potent aggregating agent for blood platelets. J Cell Biol 1974; 60:325-36. [PMID: 4360292 PMCID: PMC2109156 DOI: 10.1083/jcb.60.2.325] [Citation(s) in RCA: 95] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The phorbol ester 12-0-tetradecanoyl-phorbol-13-acetate, a potent tumor-promoting agent, caused irreversible platelet aggregation when more than 0.02 microM was stirred with human citrated or heparinized platelet-rich plasma (PRP). With washed platelets, 1 nM was effective. The alcohol phorbol, which has little tumor-promoting activity, failed to cause platelet aggregation. With all but low concentrations of phorbol ester, aggregation was succeeded by a rapid phase. The latter was prevented or reduced by enzymes which destroy ADP and by aspirin, was associated with a change in platelet shape, and was presumably due to released ADP. At higher concentrations, only a rapid phase was seen, and these inhibitors were not effective. Low concentrations did not aggregate platelets in PRP containing sufficient EDTA or EGTA to chelate ionized calcium or in PRP from thrombasthenic patients; higher concentrations caused slight aggregation. Both the primary, non-ADP-dependent aggregation and the rapid ADP-dependent aggregation were markedly inhibited by substances which increase cyclic AMP, metabolic inhibitors, and the sulfhydryl inhibitor N-ethylmaleimide. Phorbol ester reduced platelet cyclic AMP only when it had been previously elevated by prostaglandin E(1). 1 microM did not release beta-glucuronidase, lactic dehydrogenase, or inflammatory material from platelets in 4-5 min despite marked aggregation, but liberated all three in 30 min. The possibility is discussed that low phorbol ester concentrations cause primary aggregation by a direct action on platelet actomyosin.
Collapse
|
36
|
Pollard TD, Weihing RR. Actin and myosin and cell movement. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1974; 2:1-65. [PMID: 4273099 DOI: 10.3109/10409237409105443] [Citation(s) in RCA: 684] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
37
|
|
38
|
Young VR, Havenberg LN, Bilmazes C, Munro HN. Potential use of 3-methylhistidine excretion as an index of progressive reduction in muscle protein catabolism during starvation. Metabolism 1973; 23:1429-36. [PMID: 4749543 DOI: 10.1016/0026-0495(73)90257-6] [Citation(s) in RCA: 141] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
39
|
Tilney LG, Hatano S, Ishikawa H, Mooseker MS. The polymerization of actin: its role in the generation of the acrosomal process of certain echinoderm sperm. J Cell Biol 1973; 59:109-26. [PMID: 4356568 PMCID: PMC2110911 DOI: 10.1083/jcb.59.1.109] [Citation(s) in RCA: 270] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
When Asterias or Thyone sperm come in contact with egg jelly, a long process which in Thyone measures up to 90 microm in length is formed from the acrosomal region. This process can be generated in less than 30 s. Within this process is a bundle of microfilaments. Water extracts prepared from acetone powders of Asterias sperm contain a protein which binds rabbit skeletal muscle myosin forming a complex whose viscosity is reduced by ATP. Within this extract is a protein with the same molecular weight as muscle actin. It can be purified either by collecting the pellet produced after the addition of Mg(++) or by reextracting an acetone powder of actomyosin prepared by the addition of highly purified muscle myosin to the extract. The sperm actin can be polymerized and by electron microscopy the polymer is indistinguishable from muscle F-actin. The sperm actin was shown to be localized in the microfilaments in the acrosomal processes by: (a) heavy meromyosin binding in situ, (b) sodium dodecyl sulfate (SDS) gel electrophoresis of the isolated acrosomal processes and a comparison to gels of flagella which contain no band corresponding to the molecular weight of actin, and (c) SDS gel electrophoresis of the extract from isolated acrosomal caps. Since the precursor for the microfilaments in the unreacted sperm appears amorphous, we suspected that the force for the generation of the acrosomal process is brought about by the polymerization of the sperm actin. This supposition was confirmed, for when unreacted sperm were lysed with the detergent Triton X-100 and the state of the actin in the sperm extract was analyzed by centrifugation, we determined that at least 80% of the actin in the unreacted sperm was in the monomeric state.
Collapse
|
40
|
Hanson JP, Repke DI, Katz AM, Aledort LM. Calcium ion control of platelet thrombosthenin ATPase activity. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 314:382-9. [PMID: 4270851 DOI: 10.1016/0005-2728(73)90122-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
41
|
|
42
|
|
43
|
Abstract
Physarum myosin can be separated from actomyosin by ultracentrifugation, and purified by gel filtration. Unlike actomyosin, myosin is soluble in 0.05 M KCl in the pH range of 6-7. However, in the absence of actin, the slime mold myosin can be precipitated in 0.05 M KCl by the addition of millimolar concentrations of CaCl(2). The precipitates consist of aggregated, short bipolar filaments. Magnesium has a similar effect, but results in the precipitation of more loosely packed aggregates. The length of the compact filaments is 0.45 mum; thus, predominantly tail-to-tail, but also some head-to-tail, interactions occur under these conditions. Since the size and shape of these thick filaments are close to those seen in fixed and sectioned ameboid cells and in platelets, all of these filaments are probably composed of myosins.
Collapse
|