Identification of a spindle-associated protein in ciliate micronuclei

1989 ◽  
Vol 93 (2) ◽  
pp. 287-298
Author(s):  
GUY KERYER ◽  
NICOLE GARREAU DE LOUBRESSE ◽  
NICOLE BORDES ◽  
MICHEL BORNENS
Keyword(s):  
Cell Cycle ◽  
Monoclonal Antibody ◽  
Nuclear Envelope ◽  
Mammalian Cells ◽  
Fibrous Material ◽  
Cortical Microtubule ◽  
Ciliated Protozoa ◽  
Paramecium Tetraurelia ◽  
Electron Microscope Level ◽  
Microtubule Organizing Centres

Ciliated protozoa display a nuclear dualism, with germinal micronuciei and a somatic macronucleus. During mitosis, which proceeds without disruption of the nuclear envelope, a spindle is organized within the micronucleus from, presumably, intranuclear microtubule-organizing centres (MTOCs). In order to characterize these MTOCs, monoclonal antibodies generated against human centrosomes were screened on several ciliates and particularly on Paramecium tetraurelia. In this ciliate, the monoclonal antibody CTR 532, which decorates centrosomal and spindle-associated components in mammalian cells, specifically labelled the micronuclei during interphase. At the electron-microscope level, it stained a fibrous material surrounding microtubules localized on the inner face of the nuclear envelope. During mitosis this decoration extended all over the metaphase spindle. At all stages of the cell cycle, the decoration remained specific to the micronucleus and was absent not only from all of the various cytoplasmic and cortical microtubule arrays but also from the macronuclei, even at early stages of their development from the zygotic nucleus. CTR 532 recognizes a single 170x103 Mr polypeptide in the cytoskeletal fraction that contains micronuclei and this polypeptide is absent in the cytoskeletal fraction of amicronucleate cells.

A gamma-tubulin-related protein associated with the microtubule arrays of higher plants in a cell cycle-dependent manner

1993 ◽  
Vol 104 (4) ◽  
pp. 1217-1228 ◽  
Author(s):  
B. Liu ◽  
J. Marc ◽  
H.C. Joshi ◽  
B.A. Palevitz
Keyword(s):  
Cell Cycle ◽  
Mammalian Cells ◽  
Higher Plants ◽  
Cortical Microtubule ◽  
Metaphase Plate ◽  
Preprophase Band ◽  
Cell Plate ◽  
Dependent Manner ◽  
Gamma Tubulin ◽  
Cycle Dependent

An antibody specific for a conserved gamma-tubulin peptide identifies a plant polypeptide of 58 kDa. gamma-Tubulin antibody affinity purified from this polypeptide recognizes the centrosome in mammalian cells. Using immunofluorescence microscopy, we determined the distribution of this gamma-tubulin-related polypeptide during the complex changes in microtubule arrays that occur throughout the plant cell cycle. We report a punctate association of gamma-tubulin-related polypeptide with the cortical microtubule array and the preprophase band. As cells enter prophase, gamma-tubulin-related polypeptide accumulates around the nucleus and forms a polar cap from which early spindle microtubules radiate. During metaphase and anaphase, gamma-tubulin-related polypeptide preferentially associates with kinetochore fibers and eventually accumulates at the poles. In telophase, localization occurs over the phragmoplast. gamma-Tubulin-related polypeptide appears to be excluded from the plus ends of microtubules at the metaphase plate and cell plate. Its distribution during the cell cycle may be significant in light of differences in the behavior and organization of plant microtubules. The identification of gamma-tubulin-related polypeptide could help characterize microtubule organizing centers in these organisms.

scholarly journals NUCLEAR MEMBRANE FUSION IN FERTILIZED LYTECHINUS VARIEGATUS EGGS

1973 ◽  
Vol 58 (1) ◽  
pp. 126-134 ◽  
Author(s):  
John F. Aronson
Keyword(s):  
Cell Cycle ◽  
Nuclear Envelope ◽  
Fibrous Material ◽  
Experimental Approach ◽  
Nuclear Fusion ◽  
Experimental System ◽  
Lytechinus Variegatus ◽  
Cleavage Division ◽  
Binucleate Cells ◽  
Multinucleated Cells

Fusion of apposed nuclear envelopes is frequently seen at telophase during postmitotic reorganization of the nucleus, but only rarely at other times in the cell cycle. We attempted to define an experimental system for studying changes in the nuclear envelope related to the cell cycle by varying the time of pronuclear apposition in fertilized Lytechinus variegatus eggs. This approach was based on the assumption that the period from fertilization to metaphase of the first cleavage division corresponds to the period from telophase to metaphase in the generalized cell cycle. The experimental approach used was to block the movement of the pronuclei with Colcemid and then to release this block at varying times after insemination by photochemically inactivating the Colcemid. The results show that apposed pronuclear envelopes can fuse from soon after insemination until the anticipated time of prometaphase. Fusion occurred in about 3 min as scored by light microscopy and this time did not vary significantly with the time after insemination. The potential for nuclear fusion is not restricted to pronuclei alone since diploid nuclei in binucleate cells could be fused using centrifugation in solutions of Colcemid to bring the nuclei into apposition. It is suggested that the potential for nuclear fusion is not necessarily related to the cell cycle and that modification of the nuclear envelope, possibly by association with chromatin or other fibrous material restricts nuclear fusion in most multinucleated cells.

scholarly journals A monoclonal antibody against the nucleus reveals the presence of a common protein in the nuclear envelope, the perichromosomal region, and cytoplasmic vesicles.

1987 ◽  
Vol 104 (1) ◽  
pp. 1-7 ◽  
Author(s):  
M Wataya-Kaneda ◽  
Y Kaneda ◽  
T Sakurai ◽  
H Sugawa ◽  
T Uchida
Keyword(s):  
Monoclonal Antibody ◽  
Nuclear Envelope ◽  
Mammalian Cells ◽  
Immunoblot Analysis ◽  
Antigenic Determinants ◽  
Reactive Site ◽  
Premature Chromosome Condensation ◽  
Cytoplasmic Vesicles ◽  
Interphase Cells ◽  
Immunofluorescence Studies

A monoclonal antibody that recognizes antigenic determinants on the nucleus of cultured mammalian cells was isolated. Immunofluorescence studies using this antibody showed that the recognized antigen was present not only on the nucleus but also in cytoplasmic vesicles of interphase cells and in the perichromosomal region of mitotic cells. Premature chromosome condensation analysis showed that the reactive site for this monoclonal antibody could be detected in the perichromosomal region during the G2 and M phases, but not during the G1 and S phases. Finally, immunoblot analysis showed that this monoclonal antibody prepared against the nucleus recognized a protein of approximately 40 kD both in the cytoplasm and in the perichromosomal regions.

A monoclonal antibody, raised against mammalian centrosomes and screened by recognition of plant microtubule organizing centers, identifies a pericentriolar component in different cell types

1992 ◽  
Vol 101 (4) ◽  
pp. 823-835 ◽  
Author(s):  
V. Chevrier ◽  
S. Komesli ◽  
A.C. Schmit ◽  
M. Vantard ◽  
A.M. Lambert ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Monoclonal Antibody ◽  
Mammalian Cells ◽  
Cell Types ◽  
Immunoblot Analysis ◽  
Dependent Manner ◽  
Specific Staining ◽  
Microtubule Organizing Centers ◽  
Pericentriolar Material ◽  
Cycle Dependent

We have used monoclonal antibodies raised against isolated native calf thymus centrosomes to probe the structure and composition of the pericentriolar material. To distinguish prospective antibodies as specific to conserved elements of this material, we screened clones by their identification of microtubule organizing centers (MTOCs) in different animal and plant cells. Among the clonal antibodies that reacted with MTOCs in both plant and mammalian cells, we describe one (mAb 6C6) that was found to immunostain centrosomes in a variety of bovine and human cells. In cycling cells this signal persisted through the entire cell cycle. Microscopy showed that the mAb 6C6 antigen was a component of the pericentriolar material and this was confirmed by biochemical analysis of centrosomes. Using immunoblot analysis of protein fractions derived from purified components of centrosomes, we have characterized the mAb 6C6 antigen as a 180 kDa polypeptide. We conclude that we have identified a protein component permanently associated with the pericentriolar material. Surprisingly, monoclonal antibody 6C6 also stained other mitotic organelles in mammalian cells, in a cell-cycle-dependent manner. During prometaphase and metaphase the antibody stained both centrosomes and kinetochores. At the onset of anaphase the kinetochore-specific staining dissociated from chromosomes and was subsequently redistributed onto a newly characterized organelle, the telophase disc while the centrosomal stain remained intact. It is not known if the 180 kDa centrosomal protein itself redistributes during mitosis, or if the pattern observed represents other antigens with shared epitopes. The pericentriolar material is thought to be composed of conserved elements, which appeared very early during the evolution of eukaryotes. Our results strongly suggest that mAb 6C6 identifies one of these elements.

Cell cycle-dependent reactivity with the monoclonal antibody Ki-67 during myeloid cell differentiation

1988 ◽  
Vol 179 (1) ◽  
pp. 79-88 ◽  
Author(s):  
Robert P. Wersto ◽  
Fritz Herz ◽  
Robert E. Gallagher ◽  
Leopold G. Koss
Keyword(s):  
Cell Cycle ◽  
Monoclonal Antibody ◽  
Cell Differentiation ◽  
Myeloid Cell ◽  
Ki 67 ◽  
Cycle Dependent

scholarly journals OASIS/CREB3L1 is a factor that responds to nuclear envelope stress

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yasunao Kamikawa ◽  
Atsushi Saito ◽  
Koji Matsuhisa ◽  
Masayuki Kaneko ◽  
Rie Asada ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Genome Instability ◽  
Nuclear Lamina ◽  
Nuclear Deformation ◽  
Membrane Domain ◽  
Stress Response Pathway ◽  
Envelope Stress ◽  
Genome Activity

AbstractThe nuclear envelope (NE) safeguards the genome and is pivotal for regulating genome activity as the structural scaffold of higher-order chromatin organization. NE had been thought as the stable during the interphase of cell cycle. However, recent studies have revealed that the NE can be damaged by various stresses such as mechanical stress and cellular senescence. These types of stresses are called NE stress. It has been proposed that NE stress is closely related to cellular dysfunctions such as genome instability and cell death. Here, we found that an endoplasmic reticulum (ER)-resident transmembrane transcription factor, OASIS, accumulates at damaged NE. Notably, the major components of nuclear lamina, Lamin proteins were depleted at the NE where OASIS accumulates. We previously demonstrated that OASIS is cleaved at the membrane domain in response to ER stress. In contrast, OASIS accumulates as the full-length form to damaged NE in response to NE stress. The accumulation to damaged NE is specific for OASIS among OASIS family members. Intriguingly, OASIS colocalizes with the components of linker of nucleoskeleton and cytoskeleton complexes, SUN2 and Nesprin-2 at the damaged NE. OASIS partially colocalizes with BAF, LEM domain proteins, and a component of ESCRT III, which are involved in the repair of ruptured NE. Furthermore, OASIS suppresses DNA damage induced by NE stress and restores nuclear deformation under NE stress conditions. Our findings reveal a novel NE stress response pathway mediated by OASIS.

scholarly journals Mutational analyses of fs(1)Ya, an essential, developmentally regulated, nuclear envelope protein in Drosophila.

Genetics ◽  
1995 ◽  
Vol 141 (4) ◽  
pp. 1473-1481 ◽  
Author(s):  
J Liu ◽  
K Song ◽  
M F Wolfner
Keyword(s):  
Cell Cycle ◽  
Embryonic Development ◽  
Nuclear Envelope ◽  
Envelope Protein ◽  
Chromatin Condensation ◽  
Cell Cycle Control ◽  
Nuclear Lamina ◽  
Mitotic Division ◽  
Developmentally Regulated ◽  
Egg Maturation

Abstract The fs(1)Ya protein (YA) is an essential, maternally encoded, nuclear lamina protein that is under both developmental and cell cycle control. A strong Ya mutation results in early arrest of embryos. To define the function of YA in the nuclear envelope during early embryonic development, we characterized the phenotypes of four Ya mutants alleles and determined their molecular lesions. Ya mutant embryos arrest with abnormal nuclear envelopes prior to the first mitotic division; a proportion of embryos from two leaky Ya mutants proceed beyond this but arrest after several abnormal divisions. Ya unfertilized eggs contain nuclei of different sizes and condensation states, apparently due to abnormal fusion of the meiotic products immediately after meiosis. Lamin is localized at the periphery of the uncondensed nuclei in these eggs. These results suggest that YA function is required during and after egg maturation to facilitate proper chromatin condensation, rather than to allow a lamin-containing nuclear envelope to form. Two leaky Ya alleles that partially complement have lesions at opposite ends of the YA protein, suggesting that the N- and C-termini are important for YA function and that YA might interact with itself either directly or indirectly.

Cell cycle controls and the role of nerves and the regenerate epithelium in urodele forelimb regeneration: possible modifications of basic concepts

1987 ◽  
Vol 65 (8) ◽  
pp. 739-749 ◽  
Author(s):  
Roy A. Tassava ◽  
David J. Goldhamer ◽  
Bruce L. Tomlinson
Keyword(s):  
Cell Cycle ◽  
Monoclonal Antibody ◽  
Limb Regeneration ◽  
Blastema Formation ◽  
Basic Concepts ◽  
Regenerate Epithelium ◽  
Early Wound ◽  
Skin Epidermis ◽  
Wound Epithelium

Data from pulse and continuous labeling with [3H]thymidine and from studies with monoclonal antibody WE3 have led to the modification of existing models and established concepts pertinent to understanding limb regeneration. Not all cells of the adult newt blastema are randomly distributed and actively progressing through the cell cycle. Instead, many cells are in a position that we have designated transient quiescence (TQ) and are not actively cycling. We postulate that cells regularly leave the TQ population and enter the actively cycling population and vice versa. The size of the TQ population may be at least partly determined by the quantity of limb innervation. Larval Ambystoma may have only a small or nonexisting TQ, thus accounting for their rapid rate of regeneration. Examination of reactivity of monoclonal antibody WE3 suggests that the early wound epithelium, which is derived from skin epidermis, is later replaced by cells from skin glands concomitant with blastema formation. WE3 provides a useful tool to further investigate the regenerate epithelium.

Sign in / Sign up

Export Citation Format

Share Document