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At least 19 recordsLinked to original sources
PubMed1977

Immunological relation between 14 S dynein and 30 S dynein from the cilia of Tetrahymena pyriformis.

The immunological relation between 14 S dynein and 30 S dynein obtained from Tetrahymena cilia was investigated by using antisera specific for each dynein subunit or some dynein subunits separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Although 14 and 30 S dynein main subunits have different electrophoretic mobilities, our immunodiffusion tests showed that there exists a close immunological relation between them. At least three immunologically different polypeptides designated polypeptides A, B and C are included in the 30 S dynein main band which has been recognized as a single component by electrophoresis, and that the polypeptides designated A',B' and C' are included in the 14 S dynein main bands. Polypeptides A and A',B and B', or C and C' appeared to have a certain common antigenic determinant(s). Polypeptide C of 30 S dynein was shown to possess a certain antigenic determinant(s) specific for 30 S dynein, besides the determinant common with that of polypeptide C' of 14S dynein. The second main component of 30 S dynein proved to be a specific polypeptide of 30 S dynein but not to be a degraded product of the main polypedtide. All antisera reacted with native dynein molecules to some extent, but did not inhibit dynein ATPase (ATP phosphohydrase, EC 3.6.1.3) activity significantly.

Adenosine Triphosphatases↗
PubMed1977

Interactions of Tetrahymena dynein with microtubule protein. Tubulin-induced stimulation of dynein ATPase activity.

The ATPase (EC 3.6.1.3) activity of 30 S dynein from Tetrahymena cilia was remarkably stimulated by porcine brain tubulin at pH 10. The activity increased with increasing concentration of tubulin until the molar ratio of tubulin dimer to 30 S dynein reached approx. 10. The optimum of the ATPase activity of 30 S dynein in the presence of tubulin was 1-2 mM for MgCl2 and 2 mM for CaCl2. Increasing ionic strength gradually inhibited the stimulation effects of tubulin. Activation energies of 30 S dynein in the presence and absence of tubulin were almost the same. At the temperatures beyond 25 degrees C stimulation effects of tubulin disappeared. ATP was a specific substrate even in the presence of tubulin. In kinetic investigations parallel reciprocal plots were observed in a constant ratio of divalent cations to ATP of 2, indicating that tubulin was less tightly bound to 30 S dynein in the presence of ATP than the absence. The similar results were obtained at pH 8.2. 14 S dynein and the 12 S fragment which have poor ability to recombine with outer fibers were also activated with brain tubulin.

Adenosine Triphosphatases↗
PubMed1975

Preparation of antiserum against a tryptic fragment (fragment A) of dynein and an immunological approach to the subunit composition of dynein.

An improved method for purifying the tryptic fragment (Fragment A) of flagellar ATPase (dynein) from sea urchin spermatozoa is described. The preparation appears homogeneous as judged by ultracentrifugation, electrophoresis on polyacrylamide gels, and immunological techniques. The molecular weight of undenatured Fragment A was determined to be 400,000 and 370,000 by the two methods of disc electrophoresis on polyacrylamide gel and sedimentation equilibrium, respectively. The fragment dissociated into two principal polypeptide chains with molecular weights of 190,000 and 135,000 when heated in the presence of sodium dodecyl sulfate. Antiserum against dynein was prepared in rabbits using purified Fragment A from the sea urchin Anthocidaris crassispina as an antigen. The specificity of this serum toward Fragment A and toward dynein was determined by double diffusion in agarose, by inhibition of ATPase activity, and by sodium dodecyl sulfate-electrophoresis of the antigen-antibody complex. This antiserum also reacted with the enzymes from two other species of sea urchin, Pseudocentrotus depressus and Hemicentrotus pulcherrimus. Analysis of the precipitated antigen-antibody complex showed that the antiserum reacted specifically with the "high molecular weight" polypeptide seen in sodium dodecyl sulfate-polyacrylamide gel electrophoresis of crude dynein fractions. This finding supports previous reports that this band derives from dynein ATPase. In our preparations, this "high molecular weight" dynein band appeared single.

Adenosine Triphosphatases↗
PubMed1979

Kinetic properties of dynein ATPase from Tetrahymena pyriformis. The initial phosphate burst of dynein ATPase and its interaction with ATP analogs.

1. Dynein was extracted with 0.5 M KCl from Tetrahymena axonemes. SDS-gel electrophoresis of the extract indicated that about 50% of the extracted protein had a molecular weight of about 3.5 X 10(5), and that 90% of the proteins with this weight had been extracted. 2. The ATPase [EC 3.6.1.3] reaction of the KCl-extracted dynein fraction was enhanced by 60-80% by addition of the outer doublet fraction. It showed an initial burst of Pi liberation of about 1 mol per mol of proteins with a molecular weight of 3.5 X 10(5). 3. We examined the interaction of the dynein-tubulin system from Tetrahymena cilia with ten ATP analogs [2'-dATP, 3'-dATP, epsilonATP, FTP, 8-NH(CH3)-ATP, 8,3'-S-cyclo-ATP, 8-Br-ATP, 8-OCH3-ATP, 8-SCH3-ATP, and AMPPNP]. Among them, 2'-dATP and 3'-dATP were good substrates for dynein ATPase, as they induced the dissociation of dynein arms from the B-tubule of outer doublets, the sliding movement between outer doublets, and the bending movement of axonemes. The other analogs did not induce the dissociation or the sliding movement. 4. Among the ATP analogs tested, only 2'-dATP and 3'-dATP induced the reorientation of cilia on the Triton model of Tetrahymena; the reorientation rates were smaller than that induced by ATP.

Adenosine Triphosphatases↗
PubMed1976

Dynein 2. A new adenosine triphosphatase from sea urchin sperm flagella.

A new ATPase electrophoretically and immunologically distinct from the dynein ATPase studied previously has been solublized and purified from sea urchin sperm flagella. This ATPase has properties similar to those of dynein ATPase. Therefore, we propose that the two ATPases be considered as dynein isoenzymes, with previously studied dynein being known as dynein 1, and the newly discovered ATPase as dynein 2. Some physicochemical and enzymatic properties of dynein 2 have been determined. The molecular weight calculated from the sedimentation coefficient (12.3 "/- 1 S) and Stokes radius (12.8 "/- 0.4 nm) is 690,000 +/- 70,000. The molecular weight of the high molecular weight subunit of dynein 2 has been determined to be 325,000 +/- 40,000 by Na dodecyl-SO4-polyacrylamide gel electrophoresis. The enzymatic properties of dynein 1 and dynein 2 are similar in substrate specificity, pH optimum, and Mg2+ requirement for ATPase activity, but they differ in their Michaelis constant and in their dependence of ATPase activity upon salt concentration. Digestion of dynein 2 with trypsin yields an ATPase-containing protein fragment, similar to Fragment A obtained from dynein 1. An antiserum prepared against Fragment A from dynein 1 did not precipitate dynein 2 or inhibit its ATPase activity.

Adenosine Triphosphatases↗
PubMed1977

Effect of spin-labeled maleimide on 14S and 30S dyneins in solution and on demembranated ciliary axonemes.

The effects of N-1-oxyl-2,2,6,6-tetramethyl-4-piperidinyl)maleimide(SLM) on the pellet height response and ATPase activity of glycerinated Triton X-100 extracted cilia of Tetrahymena pyriformis have been studied. Preincubation of cilia with SLM caused complete inhibition of the pellet height response and an initial increase in ATPase activity followed upon longer exposure to SLM by inhibition of ATPase. The effect of SLM on extracted 30S dynein was the reverse of that for whole cilia: ATPase activity was increased when 30S dynein was added to a mixture of ATP and SLM and inhibited when the 30S dynein was preincubated with SLM. The activity of 14S dynein was only inhibited by SLM. Electron spin resonance spectra of ciliary axonemes that had reacted with SLM for various times showed that much of the covalently bound SLM was strongly immobilized even after 1 min of reaction, when ATPase activity increased twofold. The proportion of strongly immobilized label increased with longer times of reaction. Addition of ATP to SLM-labeled axonemes caused a small decrease in the height of the spectral peak corresponding to strongly immobilized label as compared with that of weakly immobilized label, indicating an increase in rotational freedom of some covalently bound label. The results suggest that ATP causes a conformation change affecting a sulfhydryl group(s) involved in the mechanochemical system. It was also shown that beta,gamma-methylene ATP(AMP-PCP) is an inhibitor of dynein ATPase. This analogue of ATP is not hydrolyzed by whole cilia or by the extracted dyneins and does not cause a pellet height response. With Mg2+ as divalent cation, AMP-PCP inhibits 30S dynein more than it inhibits 14S dynein; with Ca2+, the inhibition of 30S dynein is reduced, and there is no inhibition of 14S dynein. Under conditions where AMP-PCP inhibited 30S dynein ATPase it was much less effective than ATP in protecting against the loss of ATPase activity by SLM. Although SLM inhibited Mg2+-activated 14S and 30S dyneins in solution, it did not inhibit ciliary ATPase activity. These results support the view that at least 2 SH groups are involved in ciliary motility and that their reactivity to SH reagents depends on whether the dyneins are in situ or have been extracted.

Adenosine Triphosphatases↗
PubMed1977

Tryptic fragmentation of 30-S dynein from Tetrahymena cilia.

30-S dynein ATPase from Tetrahymena cilia was digested with trypsin (dynein: trypsin = 20:1, by weight) at 25 degrees C for 20 min, resulting in the release of a 12-S fragment possessing ATPase activity. The 12-S ATPase fraction obtained by sucrose gradient centrifugation contained several polypeptide chains as indicated by SDS gel electrophoresis. The largest chain was smaller than the subunit of 30-S dynein and almost the same size as 14-S dynein. On the other hand, when 14-S dynein was digested in a similar manner, its sedimentation value changed from 14 to 12 S, but the peak of ATPase activity was retained at 14 S, suggesting differences in amino acid sequences between the 30 and 14-S dyneins. When the time course of tryptic digestion of 30-S dynein was investigated in a trypsin:dynein ratio of 1:200, discrete fragmentation took place, producing an intermediate fragment of 24 S and the 12-S fragment. The 24-S fragment recombined with outer fibers to some extent, while the 12-S fragment lacked this ability. However, the 12-S fragment was somewhat stimulated to recombine with outer fibers in the presence of other components involved in the trypsin digest. The enzymatic characteristics of the 12-S fraction were different from those of 30-S dynein, especially the activity dependence on pH showing a typical bell-shaped curve.

Adenosine Triphosphatases↗
PubMed1977

Effects of adenosine triphosphate on N-ethylmaleimide-induced modification of 30S dynein from Tetrahymena cilia.

Ciliary 30S dynein of Tetrahymena was investigated with regard to modification of the ATPase activity with N-ethylmaleimide (NEM) in the presence of ATP. The elevation of enzyme activity due to the modification was largely repressed by addition of ATP at a concentration of 1 mM or more during preincubation of 20 h at 0 degrees C. The repression was highly specific for ATP, though ADP and AMPPNP showed slight repressive effects. After complete hydrolysis of ATP added to the preincubation mixture, however, elevation of 30S dynein ATPase activity occurred. It is suggested that the repression by ATP of NEM-induced elevation of 30S dynein ATPase activity is simply due to a protecting effect of ATP on certain SH group(s) (probably SH1-type group(s)) around the active center of 30S dynein. When 30S dynein was maximally activated by modification with NEM, ATP or ADP did not significantly promote the inactivation of the modified enzyme upon further treatment with NEM, indicating that 30S dynein lacks the characteristics of SH2-type groups. On the other hand, ATP also showed a protective effect against inhibition of native 30S dynein by high concentrations of NEM. High concentrations of ADP and AMPPNP were inhibitory to 30S dynein ATPase activity but inorganic phosphate did not inhibit 14S or 30S dynein ATPase activities at all.

Adenosine Diphosphate↗
PubMed1979

A latent adenosine triphosphatase form of dynein 1 from sea urchin sperm flagella.

Treatment of demembranated sea urchin sperm axonemes with an extraction solution containing 0.6 M NaCl, pH 7.0 for 10 min at 4 degrees C yields a solution of dynein 1 having a low, latent specific ATPase activity of about 0.25 mumol of Pi mg(-1) min(-1). Exposure of this dynein solution to 0.1% Triton-X-100 for 10 min at 25 degrees C causes an increase in its ATPase activity to about 3 mumol of Pi mg(-1) min(-1). A similar activation can be obtained by treating at 42 degrees C or by reacting with 60 mol of p-chloromercuribenzene sulfonate/10(6) g of protein. The effects of these activating procedures are not additive, suggesting that they lead to a common activated state. Purification of the latent activity dynein 1 by sucrose density gradient centrifugation yields a monodisperse preparation sedimenting at 21 S, and having a molecular weight of 1,250,000 as determined by sedimentation diffusion and sedimentation equilibrium. Activation of the latent dynein 1 with Triton X-100 converts it to a form sedimenting at 10 to 14 S. The 21 S dynein is also converted to a 10 S form by dialysis against 5 mM imidazole/NaOH buffer, 0.1 mM EDTA, 5 mM 2-mercaptoethanol, pH 7, although in this case, the ATPase activity is increased only about 3-fold, with another 3-fold activation being obtainable upon subsequent treatment with Triton X-100. The 21 S latent form of dynein 1 may represent the intact dynein arms that form moving cross-bridges and generate active sliding between adjacent doublet tubules of the flagellar axoneme. Electrophoretic analysis on polyacrylamide gels in the presence of sodium dodecyl sulfate suggests a model in which the 21 S dynein 1 particle is composed of three subunits of about 330,000 daltons and one of each of three medium weight subunits of 126,000, 95,000, and 77,000 daltons. When latent dynein 1 is added back to NaCl-extracted axonemes in the presence of 0.15 M NaCl, it recombines stoichiometrically and restores the arms on the doublet tubules with a 6-fold activation of its ATPase activity measured in the absence of KCl.

4-Chloromercuribenzenesulfonate↗
PubMed1975

Amino acid composition of dynein and comparison with myosin.

A comparison is made between dynein [flagellar ATPase; EC 3.6.1.3], purified from sea urchin sperm flagella, and muscle myosin. The amino acid composition of dynein was found to be statistically different from that of myosin. The same was true of their tryptic fragments retaining ATPase activity, i.e., Fragment A of dynein and heavy meromyosin. At low ionic strength, no superprecipitation took place when ATP was added to a mixture of dynein and actin, and stimulation of the Mg2+-ATPase activity of dynein remained below 50% even when a one-hundred-fold excess of actin was present. No viscosity drop was caused by adding ATP to a solution containing dynein and actin. Anti-myosin antiserum did not react with dynein, while anti-Fragment A antiserum formed no precipit-n line against myosin. Furthermore, the amount of dynein that combined with F-actin was less than one-fifth of the amount of dynein that fully combined with microtubules. These results are consistent with the dissimilarity in enzymatic and other physiocochemical properties of these two proteins.

Actins↗
PubMed1979

Effect of thiourea and substituted thioureas on dynein ATPase and on the turbidity response of Tetrahymena cilia.

The effects of thiourea and of several substituted thioureas -- phenylthiourea, alpha-naphtylthiourea, metiamide, and burimamide -- on dynein ATPase have been studied. The substituted thioureas are over 30 times more potent than thiourea in causing enhancement of 30S dynein ATPase activity and inhibition of 14S dynein ATPase activity. The effects of thiourea and phenylthiourea can be prevented by very low concentrations of beta-mercaptoethanol or dithiothreitol. Axonemal ATPase is also enhanced by the thioureas, but the reaction proceeds more slowly than for solubilized 30S dynein. Enhancement of 30S dynein ATPase by metiamide is prevented by low (approximately 1 microM) concentrations of ATP and, less effectively, by AMP-PNP, but not by AMP-PCP even though the latter is a stronger inhibitor of 30S dynein ATPase than is AMP-PNP. The thioureas inhibit the ATP-induced decrease in turbidity (measured as delta A350) of axonemal suspensions. Inhibition of the turbidity response is also prevented by low concentrations of beta-mercaptoethanol, but, in contrast to the irreversible enhancement of ATPase activity, inhibition of the turbidity response is largely reversible. The ability of 30S dynein to rebind onto twice-extracted axonemes is not changed by treatment with phenylthiourea or metiamide. These observations indicate that the thioureas react with at least two sets of SH or S--S groups on axonemes. Reaction with the group(s) on the 30S dynein causes an apparently irreversible enhancement of ATPase activity. Reaction with another group(s) causes a reversible inhibition of the turbidity response.

Adenosine Triphosphatases↗
PubMed1977

Studies on the initial phase of dynein ATPase activity.

Kinetic measurement of the reaction of dynein ATPase (ATP phosphohydrolase, EC 3.6.1.3) extracted from the gills of Mytilus edulis shows that in the presence of Mg2+ there is a very rapid initial liberation of Pi from the dynein-ATP system, followed by a slower liberation in the steady state. In view of following results, we have confirmed that this phenomenon is not due to the accumulation of end products, a fall in substrate concentration, nor to the presence of labile impurities in ATP but is due to the catalytic activity of dynein ATPase. 1. The replacement of native dynein by heat denatured dynein or other kinds of Mg2+-ATPase could not produce such a burst phenomenon under the same condition. 2. Both the rate of initial burst and that of steady state were proportional to enzyme content over a wide range under our standard condition. 3. Initial burst was also observed under the constant ATP level by using a ATP generate system. 4. Preincubation of dynein with Pi prior to initiation of the reaction did not eliminate the initial burst. Some properties of the initial rapid liberation of dynein ATPase were also examined. These are shown below. 5. The free ADP liberation did not show any initial burst though the Pi liberation did in the initial phase and the rate of free ADP liberation was almost equal to that of Pi liberation of the steady state. 6. Mg2+ was more effective than Ca2+ for the appearance of the initial burst while the liberation of Pi in the steady state was activated more by Ca2+ than by Mg2+. The addition of K+ in the presence of Mg2+ resulted in a marked increase of Pi liberation in the steady state but not in the initial state. 7. The activation energy of the initial burst was 9.7 kcal, which is slightly smaller than that of myosin ATPase.

Adenosine Triphosphatases↗
PubMed1979

Dynein binds to and crossbridges cytoplasmic microtubules.

Dynein isolated from Chlamydomonas flagellar axonemes binds to microtubules assembled in vitro from 6S brain tubulin dimers. The dynein arms bind periodically along the length of the microtubules with a center-to-center spacing of 24 nm, equal to the periodicity of dynein arms on intact axonemes. The arms project from the in vitro assembled microtubules at an angle of approximately 55 degrees, thereby defining microtubule polarity. Dynein cosediments with microtubules through a sucrose gradient, as demonstrated by electron microscopy, gel electrophoresis, and ATPase analysis. In addition, dynein induces crossbridging between adjacent microtubules. Darkfield microscopy reveals that microtubules containing dynein are aggregated into large bundles; electron microscopy indicates that microtubules of the same polarity are crossbridged by a regular array of arms. Viewed by darkfield microscopy, addition of ATP to crossbridged microtubules causes their disaggregation; electron microscopy shows that the majority of these microtubules are no longer crossbridged. These observations are applicable to the determination of microtubule polarity and directionality of microtubule assembly in situ and suggest a role for dynein in cytoplasmic microtubule-based cellular movements.

Adenosine Triphosphatases↗
PubMed1977

Properties of an antiserum against native dynein 1 from sea urchin sperm flagella.

Effects of an antiserum against native dynein 1 from sperm flagella of the sea urchin Strongylocentrotus purpuratus were compared with effects of an antiserum previously obtained against an ATPase-active tryptic fragment (fragment 1A) of dynein 1 from sperm flagella of the sea urchin, Anthocidaris crassispina. Both antisera precipitate dynein 1 and do not precipitate dynein 2. Only the fragment 1A antiserum precipitates fragment 1A and produces a measurable inhibition of dynein 1 ATPase activity. Both antisera inhibit the movement and the movement-coupled ATP dephosphorylation of reactivated spermatozoa. The inhibition of movement by the antiserum against dynein 1 is much less than by the antiserum against fragment 1A, suggesting that a specific interference with the active ATPase site may be required for effective inhibition of movement. Both antisera reduce the bend angle as well as the beat frequency of reactivated S. purpuratus spermatozoa, suggesting that the bend angle may depend on the activity of the dynein arms which generate active sliding.

Adenosine Triphosphatases↗
PubMed1975

Recombination of ciliary dynein of Tetrahymena with the outer fibers.

Recombination of ciliary dyneins of Tetrahymena pyriformis with the outer fibers was investigated using turbidimetry, co-sedimentation analysis and electron microscopy. As reported by Gibbons, 30S dynein could recombine with the outer fibers, while 14S dynein did to so a lesser extent. At acidic pH, however, most of the 14S dynein was also rebound to the outer fibers. When an excess of crude dynein fraction was added to the outer fiber fraction at pH 8.2, electron microscopic observations showed that the outer doublet microtubules were decorated not only with arms but also with other electron-dense materials. On the other hand, when crude dynein fraction was mixed with the outer fibers in an appropriate quantity, only arms were reconstituted at the regular positions of A-subfibers. ATP had an inhibitory effect on the recombination of dynein with the outer fibers.

Adenosine Triphosphatases↗
PubMed1977

Evidence suggesting the presence of common antigenic determinant between dynein and tubulin.

The present experiments showed that the guinea pig antiserum prepared against the main polypeptides of 14 S dynein from Tetrahymena cilia reacted with sea urchin sperm flagellar dynein and with bovine brain high molecular weight protein to give rise to a precipitin line confluent with that formed between the antiserum and Tetrahymena dynein. Furthermore, it was found that this antiserum also reacted with tubulins from Tetrahymena cilia, sea urchin sperm flagella and bovine brain to give rise to the confluent precipitin line. Among muscle proteins, only actin preparation from rabbit skeletal muscle reacted with the anti-Tetrahymena dynein serum, whereas neither rabbit skeletal muscle myosin, chicken skeletal muscle tropomyosin nor chicken skeletal muscle troponin reacted with the antiserum. These results suggest that dynein and tubulin and probably actin share an antigenic determinant regardless of different protein species and of different animal species. The common antigenic determinant was detected only when the proteins denatured with urea/sodium dodecyl sulfate/beta-mercaptoethanol/N-ethylmaleimide were used, but it was not detected at all when the native proteins were used. This implies that a certain common antigenic determinant which is involved in the precipitin line formation exists in the primary structures of dyneins and tubulins and probably actin, and is hidden inside the tertiary structures of the native protein molecules.

Adenosine Triphosphatases↗
PubMed1979

Studies of dynein from Tetrahymena cilia using agarose polyacrylamide gel electrophoresis.

Described in this report is an application of agarose-polyacrylamide gel electrophoresis, which separates protein components of crude dynein fraction (Fraction I by Gibbons) derived from Tetrahymena cilia. By this method, the fraction was separated into three protein components (designated as bands I, II and III) on the gel. When the gel was actively stained for dynein ATPase, a single band appeared, which coincided with the position of band I. A purified dynein prepared by controlled pore glass (CPG-10) column chromatography and followed by Biogel A-15m filtration showed one band on the gel at the same position as band I. These results suggest that among these three protein components, band I represents dynein and bands II and III are derived form non-ATPase protein. 'Burstic phenomenon' was also observed on their ATPase activity when axoneme or crude dynein fractions were used for ATPase assay, while the phenomenon was almost extinguished when partially purified dynein after controlled pore glass column chromatography was used as sample.

Adenosine Triphosphatases↗