scholarly journals Multiple Functions of Fubp1 in Cell Cycle Progression and Cell Survival

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1347 ◽  
Author(s):  
Mingyu Kang ◽  
Hyeon Ji Kim ◽  
Tae-Jun Kim ◽  
Jin-Seok Byun ◽  
Jae-Ho Lee ◽  
...  

The discovery of novel and critical genes implicated in malignant development is a topic of high interest in cancer research. Intriguingly, a group of genes named “double-agent” genes were reported to have both oncogenic and tumor-suppressive functions. To date, less than 100 “double-agent” genes have been documented. Fubp1 is a master transcriptional regulator of a subset of genes by interacting with a far upstream element (FUSE). Mounting evidence has collectively demonstrated both the oncogenic and tumor suppressive roles of Fubp1 and the debate regarding its roles in tumorigenesis has been around for several years. Therefore, the detailed molecular mechanisms of Fubp1 need to be determined in each context. In the present study, we showed that the Fubp1 protein level was enriched in the S phase and we identified that Fubp1 deficiency altered cell cycle progression, especially in the S phase, by downregulating the mRNA expression levels of Ccna genes encoding cyclin A. Although this Fubp1-cyclin A axis appears to exist in several types of tumors, Fubp1 showed heterogeneous expression patterns among various cancer tissues, suggesting it exhibits multiple and complicated functions in cancer development. In addition, we showed that Fubp1 deficiency confers survival advantages to cells against metabolic stress and anti-cancer drugs, suggesting that Fubp1 may play both positive and negative roles in malignant development.

1998 ◽  
Vol 72 (5) ◽  
pp. 3729-3741 ◽  
Author(s):  
Bryan S. Salvant ◽  
Elizabeth A. Fortunato ◽  
Deborah H. Spector

ABSTRACT Human cytomegalovirus (HCMV) infection inhibits cell cycle progression and alters the expression of cyclins E, A, and B (F. M. Jault, J.-M. Jault, F. Ruchti, E. A. Fortunato, C. Clark, J. Corbeil, D. D. Richman, and D. H. Spector, J. Virol. 69:6697–6704, 1995). In this study, we examined cell cycle progression, cyclin gene expression, and early viral events when the infection was initiated at different points in the cell cycle (G0, G1, and S). In all cases, infection led to cell cycle arrest. Cells infected in G0 or G1phase also showed a complete or partial absence, respectively, of cellular DNA synthesis at a time when DNA synthesis occurred in the corresponding mock-infected cells. In contrast, when cells were infected near or during S phase, many cells were able to pass through S phase and undergo mitosis prior to cell cycle arrest. S-phase infection also produced a delay in the appearance of the viral cytopathic effect and in the synthesis of immediate-early and early proteins. Labeling of cells with bromodeoxyuridine immediately prior to HCMV infection in S phase revealed that viral protein expression occurred primarily in cells which were not engaged in DNA synthesis at the time of infection. The viral-mediated induction of cyclin E, maintenance of cyclin-B protein levels, and inhibitory effects on the accumulation of cyclin A were not significantly affected when infection occurred during different phases of the cell cycle (G0, G1, and S). However, there was a delay in the observed inhibition of cyclin A in cells infected during S phase. This finding was in accord with the pattern of cell cycle progression and delay in viral gene expression associated with S-phase infection. Analysis of the mRNA revealed that the effects of the virus on cyclin E and cyclin A, but not on cyclin B, were primarily at the transcriptional level.


1998 ◽  
Vol 72 (10) ◽  
pp. 8133-8142 ◽  
Author(s):  
Yunquan Jiang ◽  
Ashfaque Hossain ◽  
Maria Teresa Winkler ◽  
Todd Holt ◽  
Alan Doster ◽  
...  

ABSTRACT Despite productive viral gene expression in the peripheral nervous system during acute infection, the bovine herpesvirus 1 (BHV-1) infection cycle is blocked in sensory ganglionic neurons and consequently latency is established. The only abundant viral transcript expressed during latency is the latency-related (LR) RNA. LR gene products inhibit S-phase entry, and binding of the LR protein (LRP) to cyclin A was hypothesized to block cell cycle progression. This study demonstrates LRP is a nuclear protein which is expressed in neurons of latently infected cattle. Affinity chromatography indicated that LRP interacts with cyclin-dependent kinase 2 (cdk2)-cyclin complexes or cdc2-cyclin complexes in transfected human cells or infected bovine cells. After partial purification using three different columns (DEAE-Sepharose, Econo S, and heparin-agarose), LRP was primarily associated with cdk2-cyclin E complexes, an enzyme which is necessary for G1-to-S-phase cell cycle progression. During acute infection of trigeminal ganglia or following dexamethasone-induced reactivation, BHV-1 induces expression of cyclin A in neurons (L. M. Schang, A. Hossain, and C. Jones, J. Virol. 70:3807–3814, 1996). Expression of S-phase regulatory proteins (cyclin A, for example) leads to neuronal apoptosis. Consequently, we hypothesize that interactions between LRP and cell cycle regulatory proteins promote survival of postmitotic neurons during acute infection and/or reactivation.


1994 ◽  
Vol 107 (1) ◽  
pp. 241-252 ◽  
Author(s):  
C. Burger ◽  
M. Wick ◽  
S. Brusselbach ◽  
R. Muller

Mitogenic stimulation of quiescent cells not only triggers the cell division cycle but also induces an increase in cell volume, associated with an activation of cellular metabolism. It is therefore likely that genes encoding enzymes and other proteins involved in energy metabolism and biosynthetic pathways represent a major class of mitogen-induced genes. In the present study, we investigated in the non-established human fibroblast line WI-38 the induction by mitogens of 17 genes whose products play a role in different metabolic processes. We show that these genes fall into 4 different categories, i.e. non-induced genes, immediate early (IE) primary genes, delayed early (DE) secondary genes and late genes reaching peak levels in S-phase. In addition, we have analysed the regulation of these genes during normal cell cycle progression, using HL-60 cells separated by counterflow elutriation. A clear cell cycle regulation was seen with those genes that are induced in S-phase, i.e. thymidine kinase, thymidylate synthase and dihydrofolate reductase. In addition, two DE genes showed a cell cycle dependent expression. Ornithine decarboxylase mRNA increased around mid-G1, reaching maximum levels in S/G2, while hexokinase mRNA expression was highest in early G1. In contrast, the expression of other DE and IE genes did not fluctuate during the cell cycle, a result that was confirmed with elutriated WI-38 and serum-stimulated HL-60 cells. These observations suggest that G0-->S and G1-->S transition are distinct processes, exhibiting characteristic programmes of gene regulation, and merging around S-phase entry.


2006 ◽  
Vol 26 (12) ◽  
pp. 4701-4711 ◽  
Author(s):  
Courtney G. Havens ◽  
Alan Ho ◽  
Naohisa Yoshioka ◽  
Steven F. Dowdy

ABSTRACT Proliferating cells have a higher metabolic rate than quiescent cells. To investigate the role of metabolism in cell cycle progression, we examined cell size, mitochondrial mass, and reactive oxygen species (ROS) levels in highly synchronized cell populations progressing from early G1 to S phase. We found that ROS steadily increased, compared to cell size and mitochondrial mass, through the cell cycle. Since ROS has been shown to influence cell proliferation and transformation, we hypothesized that ROS could contribute to cell cycle progression. Antioxidant treatment of cells induced a late-G1-phase cell cycle arrest characterized by continued cellular growth, active cyclin D-Cdk4/6 and active cyclin E-Cdk2 kinases, and inactive hyperphosphorylated pRb. However, antioxidant-treated cells failed to accumulate cyclin A protein, a requisite step for initiation of DNA synthesis. Further examination revealed that cyclin A continued to be ubiquitinated by the anaphase promoting complex (APC) and to be degraded by the proteasome. This antioxidant arrest could be rescued by overexpression of Emi1, an APC inhibitor. These observations reveal an intrinsic late-G1-phase checkpoint, after transition across the growth factor-dependent G1 restriction point, that links increased steady-state levels of endogenous ROS and cell cycle progression through continued activity of APC in association with Cdh1.


2003 ◽  
Vol 31 (2) ◽  
pp. 366-370 ◽  
Author(s):  
S.M. Oredsson

The driving force of the cell cycle is the activities of cyclin-dependent kinases (CDKs). Key steps in the regulation of the cell cycle therefore must impinge upon the activities of the CDKs. CDKs exert their functions when bound to cyclins that are expressed cyclically during the cell cycle. Polyamine biosynthesis varies bicyclically during the cell cycle with peaks in enzyme activities at the G1/S and S/G2 transitions. The enzyme activities are regulated at transcriptional, translational and post-translational levels. When cells are seeded in the presence of drugs that interfere with polyamine biosynthesis, cell cycle progression is affected within one cell cycle after seeding. The cell cycle phase that is most sensitive to polyamine biosynthesis inhibition is the S phase, while effects on the G1 and G2/M phases occur at later time points. The elongation step of DNA replication is negatively affected when polyamine pools are not allowed to increase normally during cell proliferation. Cyclin A is expressed during the S phase and cyclin A/CDK2 is important for a normal rate of DNA elongation. Cyclin A expression is lowered in cells treated with polyamine biosynthesis inhibitors. Thus, polyamines may affect S phase progression by participating in the regulation of cyclin A expression.


2013 ◽  
Vol 288 (29) ◽  
pp. 21096-21104 ◽  
Author(s):  
Miriam Vidal-Laliena ◽  
Edurne Gallastegui ◽  
Francesca Mateo ◽  
Marian Martínez-Balbás ◽  
Maria Jesús Pujol ◽  
...  

PCAF and GCN5 acetylate cyclin A at specific lysine residues targeting it for degradation at mitosis. We report here that histone deacetylase 3 (HDAC3) directly interacts with and deacetylates cyclin A. HDAC3 interacts with a domain included in the first 171 aa of cyclin A, a region involved in the regulation of its stability. In cells, overexpression of HDAC3 reduced cyclin A acetylation whereas the knocking down of HDAC3 increased its acetylation. Moreover, reduction of HDAC3 levels induced a decrease of cyclin A that can be reversed by proteasome inhibitors. These results indicate that HDAC3 is able to regulate cyclin A degradation during mitosis via proteasome. Interestingly, HDAC3 is abruptly degraded at mitosis also via proteasome thus facilitating cyclin A acetylation by PCAF/GCN5, which will target cyclin A for degradation. Because cyclin A is crucial for S phase progression and mitosis entry, the knock down of HDAC3 affects cell cycle progression specifically at both, S phase and G2/M transition. In summary we propose here that HDAC3 regulates cyclin A stability by counteracting the action of the acetylases PCAF/GCN5.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Chen-Hua Dong ◽  
Tao Jiang ◽  
Hang Yin ◽  
Hu Song ◽  
Yi Zhang ◽  
...  

AbstractColorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.


2021 ◽  
Vol 22 (11) ◽  
pp. 5483
Author(s):  
Luisa F. Bustamante-Jaramillo ◽  
Celia Ramos ◽  
Cristina Martín-Castellanos

Cyclins and CDKs (Cyclin Dependent Kinases) are key players in the biology of eukaryotic cells, representing hubs for the orchestration of physiological conditions with cell cycle progression. Furthermore, as in the case of meiosis, cyclins and CDKs have acquired novel functions unrelated to this primal role in driving the division cycle. Meiosis is a specialized developmental program that ensures proper propagation of the genetic information to the next generation by the production of gametes with accurate chromosome content, and meiosis-specific cyclins are widespread in evolution. We have explored the diversification of CDK functions studying the meiosis-specific Crs1 cyclin in fission yeast. In addition to the reported role in DSB (Double Strand Break) formation, this cyclin is required for meiotic S-phase progression, a canonical role, and to maintain the architecture of the meiotic chromosomes. Crs1 localizes at the SPB (Spindle Pole Body) and is required to stabilize the cluster of telomeres at this location (bouquet configuration), as well as for normal SPB motion. In addition, Crs1 exhibits CDK(Cdc2)-dependent kinase activity in a biphasic manner during meiosis, in contrast to a single wave of protein expression, suggesting a post-translational control of its activity. Thus, Crs1 displays multiple functions, acting both in cell cycle progression and in several key meiosis-specific events.


Marine Drugs ◽  
2019 ◽  
Vol 17 (4) ◽  
pp. 205
Author(s):  
Su-Jin Jeong ◽  
Jeong-Wook Choi ◽  
Min-Kyeong Lee ◽  
Youn-Hee Choi ◽  
Taek-Jeong Nam

Spirulina is a type of filamentous blue-green microalgae known to be rich in nutrients and to have pharmacological effects, but the effect of spirulina on the small intestine epithelium is not well understood. Therefore, this study aims to investigate the proliferative effects of spirulina crude protein (SPCP) on a rat intestinal epithelial cells IEC-6 to elucidate the mechanisms underlying its effect. First, the results of wound-healing and cell viability assays demonstrated that SPCP promoted migration and proliferation in a dose-dependent manner. Subsequently, when the mechanisms of migration and proliferation promotion by SPCP were confirmed, we found that the epidermal growth factor receptor (EGFR) and mitogen-activated protein (MAPK) signaling pathways were activated by phosphorylation. Cell cycle progression from G0/G1 to S phase was also promoted by SPCP through upregulation of the expression levels of cyclins and cyclin-dependent kinases (Cdks), which regulate cell cycle progression to the S phase. Meanwhile, the expression of cyclin-dependent kinase inhibitors (CKIs), such as p21 and p27, decreased with SPCP. In conclusion, our results indicate that activation of EGFR and its downstream signaling pathway by SPCP treatment regulates cell cycle progression. Therefore, these results contribute to the research on the molecular mechanism for SPCP promoting the migration and proliferation of rat intestinal epithelial cells.


1997 ◽  
Vol 110 (19) ◽  
pp. 2345-2357 ◽  
Author(s):  
A. Battistoni ◽  
G. Guarguaglini ◽  
F. Degrassi ◽  
C. Pittoggi ◽  
A. Palena ◽  
...  

RanBP1 is a molecular partner of the Ran GTPase, which is implicated in the control of several processes, including DNA replication, mitotic entry and exit, cell cycle progression, nuclear structure, protein import and RNA export. While most genes encoding Ran-interacting partners are constitutively active, transcription of the RanBP1 mRNA is repressed in non proliferating cells, is activated at the G1/S transition in cycling cells and peaks during S phase. We report here that forced expression of the RanBP1 gene disrupts the orderly execution of the cell division cycle at several stages, causing inhibition of DNA replication, defective mitotic exit and failure of chromatin decondensation during the telophase-to-interphase transition in cells that achieve nuclear duplication and chromosome segregation. These results suggest that deregulated RanBP1 activity interferes with the Ran GTPase cycle and prevents the functioning of the Ran signalling system during the cell cycle.


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