MSA-35: a protein identified by human autoantibodies that colocalizes with microtubules

1992 ◽  
Vol 70 (10-11) ◽  
pp. 1115-1122 ◽  
Author(s):  
J. B. Rattner ◽  
T. Wang ◽  
G. Mack ◽  
L. Martin ◽  
M. J. Fritzler
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Hela Cells ◽  
Temporal Distribution ◽  
Mitotic Arrest ◽  
Spatial And Temporal Distribution ◽  
Intercellular Bridge ◽  
Centrosome Separation ◽  
Interphase Cells ◽  
Low Levels

We have identified a putative 35-kilodalton protein that colocalizes with microtubules and displays a unique spatial and temporal distribution during the cell cycle of HeLa cells. This protein has been given the designation MSA-35. MSA-35 first appears in association with microtubules and centrosomes of interphase cells exhibiting centrosome separation as a prelude to cell division. This protein is found in conjunction with kinetochore microtubules throughout their appearance. MSA-35 transiently associates with interpolar microtubules following anaphase and the pattern of MSA-35 reactivity in telophase cells suggests that there are at least seven domains within the intercellular bridge. The distribution of MSA-35 during and following recovery from mitotic arrest with nocodazole suggest that it is also present at low levels in interphase cells, can associate with interphase centrosomes, and colocalizes with nascent microtubules. The complex spatial and temporal distribution of MSA-35 indicates that it may be necessary for a series of events in the mitotic process such as the bundling of microtubules.Key words: mitosis, autoantibodies, spindle.

Dynamic changes of NuMA during the cell cycle and possible appearance of a truncated form of NuMA during apoptosis

1996 ◽  
Vol 109 (2) ◽  
pp. 277-288 ◽  
Author(s):  
H.L. Hsu ◽  
N.H. Yeh
Keyword(s):  
Cell Cycle ◽  
Hela Cells ◽  
Structural Integrity ◽  
Chromatin Condensation ◽  
Tail Domain ◽  
Truncated Form ◽  
Cdc2 Kinase ◽  
Mitotic Apparatus ◽  
Interphase Cells ◽  
Late Stages

We have demonstrated that dynamic redistribution of nuclear-mitotic apparatus (NuMA) protein in the cell cycle is correlated temporally and spatially with its biochemical modifications. In interphase, NuMA behaves solely as a 220 kDa nuclear matrix-associated protein. After initiation of DNA condensation during mitosis, NuMA is phosphorylated by Cdc2 kinase into a 240 kDa form which is transported quickly to the centrosomal region. Once cells have passed the metaphase-anaphase transition, the 240 kDa form of NuMA either becomes a 180 kDa truncated form which is fated to be degraded completely before mitotic exit, or returns to the 220 kDa form that relocates to the daughter nuclei and remains throughout interphase. Apparently, a proteolytic enzyme is activated during the late stages of mitosis. After induction of a 180 kDa form of NuMA in interphase HeLa cells by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole, nuclear apoptotic phenomena including chromatin condensation, DNA fragmentation, and micronucleation were observed. However, the same treatment did not induce apoptosis in mitotic phase-arrested HeLa cells. The 180 kDa form of NuMA was demonstrated to be a truncated product, at least lacking the tail domain. When HL60 cells were stimulated by diverse apoptosis inducers such as camptothecin, staurosporine, cycloheximide, and A23187, the extent of NuMA cleavage to produce a 180 kDa product was comparable with the degree of oligonucleosomal laddering. NuMA cleavage is likely to be a consequence of the onset of apoptosis. The intact 220 kDa NuMA functions in interphase cells to retain the nuclear structural integrity. Additionally, NuMA appears to act as a nuclear structural target for a death protease during apoptosis.

Changes in the organization of chromosomes during the cell cycle: response to ultraviolet light

1975 ◽  
Vol 17 (3) ◽  
pp. 539-565
Author(s):  
S.L. Schor ◽  
R.T. Johnson ◽  
C.A. Waldren
Keyword(s):  
Cell Cycle ◽  
Dna Synthesis ◽  
Ultraviolet Light ◽  
Hela Cells ◽  
Close Correlation ◽  
Chromosome Condensation ◽  
Unscheduled Dna Synthesis ◽  
Interphase Chromosome ◽  
Interphase Cells ◽  
Chromosome Decondensation

Fusion between mitotic and interphase cells results in the premature condensation of the interphase chromosomes into a morphology related to the position in the cell cycle at the time of fusion. These prematurely condensed chromosomes (PCC) have been used in conjunction with u.v. irradiation to examine the interphase chromosome condensation cycle of HeLa cells. The following observations have been made: (I) There is a progressive decondensation of the chromosomes during G1 which is accentuated by u.v. irradiation: (2) The chromosomes become more resistant to u.v.-induced decondensation during G2 and mitosis. (3) There is a close correlation between the degree of chromosome decondensation and the amount of unscheduled DNA synthesis induced by u.v. irradiation during G1 and mitosis: (4) Hydroxyurea enhances the ability of u.v. irradiation to promote the decondensation of chromosomes during G1, G2 and mitosis. Hydroxyurea also potentiates the lethal action of u.v. irradiation during mitosis and G1. These data are discussed in relation to the suggestion that chromosomes undergo a progressive decondensation during G1 and condensation during G2.

scholarly journals Partitioning and Exocytosis of Secretory Granules during Division of PC12 Cells

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Nickolay Vassilev Bukoreshtliev ◽  
Erlend Hodneland ◽  
Tilo Wolf Eichler ◽  
Patricia Eifart ◽  
Amin Rustom ◽  
...  
Keyword(s):  
Cell Division ◽  
Pc12 Cells ◽  
Secretory Granules ◽  
Time Lapse ◽  
Intercellular Bridge ◽  
Time Lapse Microscopy ◽  
Interphase Cells ◽  
Molecular Machinery ◽  
Spindle Microtubules ◽  
Single Granule

The biogenesis, maturation, and exocytosis of secretory granules in interphase cells have been well documented, whereas the distribution and exocytosis of these hormone-storing organelles during cell division have received little attention. By combining ultrastructural analyses and time-lapse microscopy, we here show that, in dividing PC12 cells, the prominent peripheral localization of secretory granules is retained during prophase but clearly reduced during prometaphase, ending up with only few peripherally localized secretory granules in metaphase cells. During anaphase and telophase, secretory granules exhibited a pronounced movement towards the cell midzone and, evidently, their tracks colocalized with spindle microtubules. During cytokinesis, secretory granules were excluded from the midbody and accumulated at the bases of the intercellular bridge. Furthermore, by measuring exocytosis at the single granule level, we showed, that during all stages of cell division, secretory granules were competent for regulated exocytosis. In conclusion, our data shed new light on the complex molecular machinery of secretory granule redistribution during cell division, which facilitates their release from the F-actin-rich cortex and active transport along spindle microtubules.

scholarly journals Dependence of fluorodeoxyglucose (FDG) uptake on cell cycle and dry mass: a single-cell study using a multi-modal radiography platform

2019 ◽  
Author(s):  
Yongjin Sung ◽  
Marc-Andre Tetrault ◽  
Kazue Takahashi ◽  
Jinsong Ouyang ◽  
Guillem Pratx ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Single Cell ◽  
Hela Cells ◽  
Building Blocks ◽  
Dry Mass ◽  
Proliferation Index ◽  
Cycle Phase ◽  
Proliferative Potential ◽  
Fdg Uptake

AbstractHigh glucose uptake by cancer compared to normal tissues has long been utilized in fluorodeoxyglucose-based positron emission tomography (FDG-PET) as a contrast mechanism. The FDG uptake rate has been further related to the proliferative potential of cancer, specifically the proliferation index (PI) − the proportion of cells in S, G2 or M phases. The underlying hypothesis was that the cells preparing for cell division would consume more energy and metabolites as building blocks for biosynthesis. Despite the wide clinical use, mixed reports exist in the literature on the relationship between FDG uptake and PI. This may be due to the large variation in cancer types or methods adopted for the measurements. Of note, the existing methods can only measure the average properties of a tumor mass or cell population with highly-heterogeneous constituents. In this study, we have built a multi-modal live-cell radiography system and measured the [18F]FDG uptake by single HeLa cells together with their dry mass and cell cycle phase. The results show that HeLa cells take up twice more [18F]FDG in S, G2 or M phases than in G1 phase, which confirms the association between FDG uptake and PI at a single-cell level. Importantly, we show that [18F]FDG uptake and cell dry mass have a positive correlation in HeLa cells, which suggests that high [18F]FDG uptake in S, G2 or M phases can be largely attributed to increased dry mass, rather than the activities preparing for cell division. This interpretation is consistent with recent observations that the energy required for the preparation of cell division is much smaller than that for maintaining house-keeping proteins.

scholarly journals O-GlcNAcylation of myosin phosphatase targeting subunit 1 (MYPT1) dictates timely disjunction of centrosomes

2020 ◽  
Vol 295 (21) ◽  
pp. 7341-7349 ◽  
Author(s):  
Caifei Liu ◽  
Yingxin Shi ◽  
Jie Li ◽  
Xuewen Liu ◽  
Zhikai Xiahou ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Molecular Mechanism ◽  
Hela Cells ◽  
Protein Phosphatase ◽  
Mitotic Progression ◽  
Myosin Phosphatase ◽  
Biological Assays ◽  
Centrosome Separation ◽  
Glcnac Transferase

The role of O-linked N-acetylglucosamine (O-GlcNAc) modification in the cell cycle has been enigmatic. Previously, both O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) disruptions have been shown to derail the mitotic centrosome numbers, suggesting that mitotic O-GlcNAc oscillation needs to be in concert with mitotic progression to account for centrosome integrity. Here, using both chemical approaches and biological assays with HeLa cells, we attempted to address the underlying molecular mechanism and observed that incubation of the cells with the OGA inhibitor Thiamet-G strikingly elevates centrosomal distances, suggestive of premature centrosome disjunction. These aberrations could be overcome by inhibiting Polo-like kinase 1 (PLK1), a mitotic master kinase. PLK1 inactivation is modulated by the myosin phosphatase targeting subunit 1 (MYPT1)–protein phosphatase 1cβ (PP1cβ) complex. Interestingly, MYPT1 has been shown to be abundantly O-GlcNAcylated, and the modified residues have been detected in a recent O-GlcNAc–profiling screen utilizing chemoenzymatic labeling and bioorthogonal conjugation. We demonstrate here that MYPT1 is O-GlcNAcylated at Thr-577, Ser-585, Ser-589, and Ser-601, which antagonizes CDK1-dependent phosphorylation at Ser-473 and attenuates the association between MYPT1 and PLK1, thereby promoting PLK1 activity. We conclude that under high O-GlcNAc levels, PLK1 is untimely activated, conducive to inopportune centrosome separation and disruption of the cell cycle. We propose that too much O-GlcNAc is equally deleterious as too little O-GlcNAc, and a fine balance between the OGT/OGA duo is indispensable for successful mitotic divisions.

scholarly journals Menin Associates With the Mitotic Spindle and Is Important for Cell Division

Endocrinology ◽  
2019 ◽  
Vol 160 (8) ◽  
pp. 1926-1936
Author(s):  
Mark P Sawicki ◽  
Ankur A Gholkar ◽  
Jorge Z Torres
Keyword(s):  
Cell Division ◽  
Mitotic Spindle ◽  
Multiple Endocrine Neoplasia Type ◽  
Intercellular Bridge ◽  
Sporadic Tumor ◽  
Spindle Poles ◽  
Chromosome Congression ◽  
Interphase Cells ◽  
Early Mitosis

Abstract Menin is the protein mutated in patients with multiple endocrine neoplasia type 1 (MEN1) syndrome and their corresponding sporadic tumor counterparts. We have found that menin functions in promoting proper cell division. Here, we show that menin localizes to the mitotic spindle poles and the mitotic spindle during early mitosis and to the intercellular bridge microtubules during cytokinesis in HeLa cells. In our study, menin depletion led to defects in spindle assembly and chromosome congression during early mitosis, lagging chromosomes during anaphase, defective cytokinesis, multinucleated interphase cells, and cell death. In addition, pharmacological inhibition of the menin-MLL1 interaction also led to similar cell division defects. These results indicate that menin and the menin-MLL1 interaction are important for proper cell division. These results highlight a function for menin in cell division and aid our understanding of how mutation and misregulation of menin promotes tumorigenesis.

scholarly journals Role for Wee1 in Inhibition of G2-to-M Transition through the Cooperation of Distinct Human Papillomavirus Type 1 E4 Proteins

2006 ◽  
Vol 80 (15) ◽  
pp. 7416-7426 ◽  
Author(s):  
Gillian L. Knight ◽  
Andrew S. Turnell ◽  
Sally Roberts
Keyword(s):  
Cell Cycle ◽  
Human Papillomavirus ◽  
Cell Division ◽  
Cyclin B1 ◽  
Sequential Loss ◽  
Low Levels ◽  
Interfering Rna ◽  
Infectious Cycle ◽  
Cell Cycle Status

ABSTRACT The infectious cycle of human papillomavirus type 1 (HPV1) is accompanied by abundant expression of the full-length E1^E4 protein (17-kDa) and smaller E4 polypeptides (16-, 11-, and 10-kDa) that arise by sequential loss of N-terminal E1^E4 sequences. HPV1 E4 inhibits G2-to-M transition of the cell cycle. Here, we show that HPV1 E4 proteins mediate inhibition of cell division by more than one mechanism. Cells arrested by coexpression of E1^E4 (E4-17K) and a truncated protein equivalent to the 16-kDa species (E4-16K) contain inactive cyclin B1-cdk1 complexes. Inactivation of cdk1 is through inhibitory Tyr15 phosphorylation, with cells containing elevated levels of Wee1, the kinase responsible for inhibitory cdk1 phosphorylation. Consistent with these findings, overexpression of Wee1 enhanced the extent to which E4-17K/16K-expressing cells arrest in G2, indicating that maintenance of Wee1 activity is necessary for inhibition of cell division induced by coexpression of the two E4 proteins. Moreover, we have determined that depletion of Wee1 by small interfering RNA (siRNA) alleviates the G2 block imposed by E4-17K/16K. In contrast however, maintenance of Wee1 activity is not necessary for G2-to-M inhibition mediated by E4-16K alone, as overexpression or depletion of Wee1 does not influence the G2 arrest function of E4-16K. Cells arrested by E4-16K expression contain low levels of active cyclin B1-cdk1 complexes. We hypothesize that differential expression of HPV1 E4 proteins during the viral life cycle determines the host cell cycle status. Different mechanisms of inhibition of G2-to-M transition reinforce the supposition that distinct E4 functions are important for HPV replication.

scholarly journals The UBXN-2/p37/p47 adaptors of CDC-48/p97 regulate mitosis by limiting the centrosomal recruitment of Aurora A

2013 ◽  
Vol 201 (4) ◽  
pp. 559-575 ◽  
Author(s):  
Elsa Kress ◽  
Françoise Schwager ◽  
René Holtackers ◽  
Jonas Seiler ◽  
François Prodon ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Caenorhabditis Elegans ◽  
Mitotic Spindle ◽  
Cell Cycle Regulation ◽  
Aurora A ◽  
Aaa Atpase ◽  
Centrosome Separation ◽  
Cycle Regulation

Coordination of cell cycle events in space and time is crucial to achieve a successful cell division. Here, we demonstrate that UBXN-2, a substrate adaptor of the AAA ATPase Cdc48/p97, is required to coordinate centrosome maturation timing with mitosis. In UBXN-2–depleted Caenorhabditis elegans embryos, centrosomes recruited more AIR-1 (Aurora A), matured precociously, and alignment of the mitotic spindle with the axis of polarity was impaired. UBXN-2 and CDC-48 coimmunoprecipitated with AIR-1 and the spindle alignment defect was partially rescued by co-depleting AIR-1, indicating that UBXN-2 controls these processes via AIR-1. Similarly, depletion in human cells of the UBXN-2 orthologues p37/p47 resulted in an accumulation of Aurora A at centrosomes and a delay in centrosome separation. The latter defect was also rescued by inhibiting Aurora A. We therefore postulate that the role of this adaptor in cell cycle regulation is conserved.

scholarly journals Modulation of phosphatidylinositol 4-phosphate levels by CaBP7 controls cytokinesis in mammalian cells

2015 ◽  
Vol 26 (8) ◽  
pp. 1428-1439 ◽  
Author(s):  
Dayani Rajamanoharan ◽  
Hannah V. McCue ◽  
Robert D. Burgoyne ◽  
Lee P. Haynes
Keyword(s):  
Cell Division ◽  
Hela Cells ◽  
Calcium Binding ◽  
Mammalian Cells ◽  
Calcium Binding Protein ◽  
Model Systems ◽  
Intercellular Bridge ◽  
Phosphoinositide Signaling ◽  
Novel Association ◽  
Phosphatidylinositol 4

Calcium and phosphoinositide signaling regulate cell division in model systems, but their significance in mammalian cells is unclear. Calcium-binding protein-7 (CaBP7) is a phosphatidylinositol 4-kinaseIIIβ (PI4KIIIβ) inhibitor required during cytokinesis in mammalian cells, hinting at a link between these pathways. Here we characterize a novel association of CaBP7 with lysosomes that cluster at the intercellular bridge during cytokinesis in HeLa cells. We show that CaBP7 regulates lysosome clustering and that PI4KIIIβ is essential for normal cytokinesis. CaBP7 depletion induces lysosome mislocalization, extension of intercellular bridge lifetime, and cytokinesis failure. These data connect phosphoinositide and calcium pathways to lysosome localization and normal cytokinesis in mammalian cells.

Sign in / Sign up

Export Citation Format

Share Document