An antiserum to the sea urchin 20 S egg dynein reacts with embryonic ciliary dynein but it does not react with the mitotic apparatus

1986 ◽  
Vol 118 (2) ◽  
pp. 416-424 ◽  
Author(s):  
David J. Asai
Keyword(s):  
1958 ◽  
Vol 35 (2) ◽  
pp. 407-424
Author(s):  
Y. HIRAMOTO

1. Protoplasmic movements during cleavage in the eggs of the heart-urchin Clypeaster japonicus have been followed by tracing the movements of cytoplasmic granules and of carbon particles adhering to the surface. 2. These movements are quantitatively described in normal eggs and in eggs whose mitotic apparatus has been destroyed by colchicine. 3. The results obtained are qualitatively similar to those obtained by Spek and by Dan and his collaborators. 4. Endoplasmic movement and changes in the length and shape of the astral rays are readily explained by the contracting-ring (band) theory. 5. The location of the motive force of cell division is discussed.


1978 ◽  
Vol 31 (1) ◽  
pp. 117-135
Author(s):  
Y. Masui ◽  
A. Forer ◽  
A.M. Zimmerman

Mitotic apparatus (MA) were isolated in glycerol-dimethylsulphoxide solution (MTME) from zygotes of sea urchins (Stronglyocentrotus purpuratus). Freshly isolated MA were stored in 1/10 strength MTME for varying periods of time and were then injected into unfertilized frog (Rana pipiens) eggs. These injections induced 40–60% of the recipient frog eggs to initiate cleavage, resulting in the formation of blastula cell clusters. The cleavage-inducing activity of MA stored in 1/10 MTME at room temperature decreased with time of storage in 1/10 strength MTME, and disappeared by about 6 h. There was no change in the ultrastructure of MA during storage. MA isolated and stored in MTME at room temperature had a constant level of cleavage-inducing activity during the first 48 h of storage, but this activity slowly declined upon further storage; almost no activity was left after 3 weeks. MA isolated in hexylene glycol (HG) and immediately transferred into MTME were compared with MA isolated in MTME; both MA had the same cleavage-inducing activity on the day of isolation, after which the MA isolated in HG quickly lost activity. On the other hand, MA isolated and stored in HG had little cleavage-inducing activity when tested 3 h following isolation. Cleavage-inducing agent (CIA) isolated from frog brains induced cleavage and blastula formation when injected into nucleated frog eggs, but had no such activity when injected into enucleated frog eggs. MA isolated in MTME induced cleavage and blastula formation in enucleated frog eggs as well as in nucleated frog eggs. Cytological examination revealed that blastula cells which developed from MA-injected enucleated eggs contained Feulgennegative nuclei, whereas cells which developed from CIA-injected nucleated eggs contained Feulgen-positive nuclei. These results suggest that sea-urchin nuclear materials participate in mitosis in frog eggs. Isolated MA which had been stored in MTME for 3 weeks and which exhibited little cleavage-inducing activity were injected together with frog brain CIA into either normal or enucleated eggs; normal recipient eggs cleaved with significantly higher frequencies (70%) than those injected with CIA alone (40%). Furthermore, enucleated eggs injected with CIA alone failed to cleave, while those injected with MA and CIA together cleaved with significant frequencies (overall 29%). This result suggests a cooperative interaction between CIA and the inactivated MA to restore the cleavage-inducing activity of MA.


1969 ◽  
Vol 41 (2) ◽  
pp. 577-590 ◽  
Author(s):  
Thomas Bibring ◽  
Jane Baxandall

Evidence is presented that the "22S protein" of mitotic apparatus isolated from sea urchin eggs is not microtubule protein. An antibody preparation active against 22S protein is described, and immunochemical studies of the distribution of 22S protein in various cellular fractions and among morphological features of mitotic apparatus are reported. The protein is ubiquitous in the metaphase egg fractions that were tested but is not found in sperm flagella. It is immunologically distinct from proposed microtubule protein isolated from mitotic apparatus by the method of Sakai, and from proposed microtubule protein obtained after extraction with mild acid. It exists in nontubule material of isolated mitotic apparatus but is not detectable in microtubules.


1959 ◽  
Vol 6 (3) ◽  
pp. 447-455 ◽  
Author(s):  
Hans A. Went

The primary purpose of the experiments reported in this paper was to gain information on the molecular origin of the mitotic apparatus. Antisera were prepared against unfertilized sea urchin (Strongylocentrotus purpuratus) egg antigens and mitotic apparatus antigens. These were permitted to react with various antigen solutions in Ouchterlony agar gel diffusion plates, and the resultant precipitation patterns analysed. The results revealed that the mitotic apparatus contains probably no more than two antigens (precursor-1 component and precursor-2 component) and that these are shared by the unfertilized egg. Absorption and fractionation techniques indicated that in the unfertilized egg the precursor-1 component is present both as a "soluble" protein and as an insoluble form tenaciously associated with intracellular structural elements. A survey of dividing and non-dividing tissues for the precursor-1 component revealed that it was restricted to tissues in which mitotic activity could be detected microscopically. No immunochemical relationship could be detected between the mitotic apparatus and proteins extracted, by various methods, from the lantern muscle.


Zygote ◽  
1993 ◽  
Vol 1 (3) ◽  
pp. 215-223 ◽  
Author(s):  
Hidehiko Shogomori ◽  
Kazuyoshi Chiba ◽  
Hideo Kubo ◽  
Motonori Hoshi

SummaryM5 ganglioside (NeuGcα2–6Glcβl-' Cer) is the predominant glycosphingolipid in sea urchin eggs. Distribution of M5 ganglioside was studied in unfertilised and fertilised eggs of the sea urchin Hemicentrotus pulcherrimus by indirect immunofluorescence microscopy. In the cortices of unfertilised eggs, anti-M5 antibody strongly stained the submembranous, polygonal and tubular network of endoplasmic reticulum that was revealed by a membrane-staining dye, DiIC18(3). In addition to the cortical network of endoplasmic reticulum, at least two morphologically distinct vesicles were positive to the antibody. In the cortices isolated from fertilised eggs 30 min after insemination, the antibody stained only a similar network of endoplasmic reticulum, presumably the one reconstructed 5–10 min after fertilisation. During mitosis the endoplasmic reticulum is known to aggregate within the asters of the mitotic apparatus. Indeed, the antibody stained the asters and (more strongly) the vesicular components attaching to the periphery of the mitotic apparatus.


1976 ◽  
Vol 68 (3) ◽  
pp. 440-450 ◽  
Author(s):  
J Nath ◽  
J I Rebhun

Methylxanthines (MX) inhibit cell division in sea urchin and clam eggs. This inhibitory effect is not mediated via cAMP. MX also inhibit respiration in marine eggs, at concentrations which inhibit cleavage. Studies showed that no changes occurred in ATP and ADP levels in the presence of inhibitory concentrations of MX, indicating an extra-mitochondrial site of action for the drug. Subsequent studies revealed decreased levels of NADP+ and NADPH, when eggs were incubated with inhibitory concentrations of MX, but no change in levels of NAD+ and NADH. MX did not affect the pentose phosphate shunt pathway and did not have any effect on the enzyme NAD+ -kinase. Further studies showed a marked inhibitory effect on the glutathione reductase activity of MX-treated eggs. Reduced glutathione (GSH) could reverse the cleavage inhibitory effect of MX. Moreover, diamide, a thiol-oxidizing agent specific for GSH in living cells, caused inhibition of cell division in sea urchin eggs. Diamide added to eggs containing mitotic apparatus (MA) could prevent cleavage by causing a dissolution of the formed MA. Both MX and diamide inhibit a Ca2+-activated ATPase in whole eggs. The enzyme can be reactivated by sulfhydryl reducing agents added in the assay mixture. In addition, diamide causes an inhibition of microtubule polymerization, reversible with dithioerythritol. All experimental evidence so far suggests that inhibition of mitosis in sea urchin eggs by MX is mediated by perturbations of the in vivo thiol-disulfide status of target systems, with a primary effect on glutathione levels.


1996 ◽  
Vol 109 (12) ◽  
pp. 2885-2893 ◽  
Author(s):  
E. Brisch ◽  
M.A. Daggett ◽  
K.A. Suprenant

The most abundant microtubule-associated protein in sea urchin eggs and embryos is the 77 kDa echinoderm microtubule-associated protein (EMAP). EMAP localizes to the mitotic spindle as well as the interphase microtubule array and is a likely target for a cell cycle-activated kinase. To determine if EMAP is phosphorylated in vivo, sea urchin eggs and embryos were metabolically labeled with 32PO4 and a monospecific antiserum was used to immunoprecipitate EMAP from 32P-labeled eggs and embryos. In this study, we demonstrate that the 77 kDa EMAP is phosphorylated in vivo by two distinct mechanisms. In the unfertilized egg, EMAP is constitutively phosphorylated on at least five serine residues. During the first cleavage division following fertilization, EMAP is phosphorylated with a cell cycle-dependent time course. As the embryo enters mitosis, EMAP phosphorylation increases, and as the embryo exits mitosis, phosphorylation decreases. During mitosis, EMAP is phosphorylated on 10 serine residues and two-dimensional phosphopeptide mapping reveals a mitosis-specific site of phosphorylation. At all stages of the cell cycle, a 33 kDa polypeptide copurifies with the 77 kDa EMAP, regardless of phosphorylation state. Antibodies against the cdc2 kinase were used to demonstrate that the 33 kDa polypeptide is the p34cdc2 kinase. The p34cdc2 kinase copurifies with the mitotic apparatus and immunostaining indicates that the p34cdc2 kinase is concentrated at the spindle poles. Models for the interaction of the p34cdc2 kinase and the 77 kDa EMAP are presented.


1995 ◽  
Vol 171 (1) ◽  
pp. 182-194 ◽  
Author(s):  
John H. Henson ◽  
Douglas G. Cole ◽  
Mark Terasaki ◽  
Dana Rashid ◽  
Jonathan M. Scholey

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