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Pre-malignancy was initiated by pLIMK1/2T508/T505 mislocalization leading to cytokinesis failure. (a) HTRZ and HTRY cells were induced with doxycycline for 48 h, and immunostained with α-tubulin antibody (green) to define cell boundaries. Visually, many HTRY cells were binucleate (arrows) and, thus, (b) we quantified the proportion of HTRZ and HTRY cells displaying this phenotype. In all, 200 cells were assessed in three independent experiments (**P<0.01). (c) Immunofluorescence staining was employed to evaluate the spatial localization of pLIMK1/2T508/T505 (red) and phalloidin (green) in cytokinetic HTRZ and HTRY cells following a 48-h induction with doxycycline. pLIMK1/2T508/T505 was concentrated in the cleavage furrow of HTRZ cells promoting stabilization of the actomyosin contractile ring (arrow). In HTRY cells, pLIMK1/2T508/T505 remained diffused throughout the cytoplasm, and the contractile ring failed to form (arrow).
Source publication
Y-box binding protein-1 (YB-1) expression in the mammary gland promotes breast carcinoma that demonstrates a high degree of genomic instability. In the present study, we developed a model of pre-malignancy to characterize the role of this gene during breast cancer initiation and early progression. Antibody microarray technology was used to ascertai...
Contexts in source publication
Context 1
... MDA-MB-231 cells with the RSK inhibitor BI-D1870 yielded complete suppression of pLIMK1/2 T508/T505 highlighting that pYB-1 S102 was necessary to promote LIMK1/2 activation ( Figure 1D). These data were mirrored using siRNA against RSK1 and RSK2 ( Figure S2). Previous reports implicated LIMK1/2 as centrosomal proteins ( Chakrabarti et al., 2007;Sumi et al., 2006) and, accordingly, we wanted to examine the localization in our HTRY cell model. ...
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... YB-1 regulating a myriad of cell cycle associated genes, we wondered how cells from a non-malignant background would respond to expression of the gene. One of the earliest and most remarkable changes in the HTRY cells following YB-1 induction was the strikingly high incidence of multinucleated cells (Figure 2A). At 48 hours following YB-1 induction, which corresponded roughly to the doubling time of these cells (data not shown), 28% of HTRY cells were binucleate thus indicating a failure of cytokinesis. ...
Context 3
... 48 hours following YB-1 induction, which corresponded roughly to the doubling time of these cells (data not shown), 28% of HTRY cells were binucleate thus indicating a failure of cytokinesis. This was compared to only 5% of HTRZ cells ( Figure 2B). ...
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... cytokinetic HTRZ cells, pLIMK1/2 T508/T505 was concentrated in the junction between the two daughter cells as observed by immunofluorescence. Accordingly, F-actin was visualized, using phalloidin, along the cleavage furrow and at the nuclear periphery ( Figure 2C). On the other hand, in cytokinetic HTRY cells, pLIMK1/2 T508/T505 was strongly expressed but remained diffuse throughout the cytoplasm ( Figure 2C). ...
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... F-actin was visualized, using phalloidin, along the cleavage furrow and at the nuclear periphery ( Figure 2C). On the other hand, in cytokinetic HTRY cells, pLIMK1/2 T508/T505 was strongly expressed but remained diffuse throughout the cytoplasm ( Figure 2C). Consequently, the actin cytoskeleton failed to reposition itself for cytokinesis. ...
Citations
... Phosphorylated YB-1 localizes to mitotic centrosomes [43]. Loss of YB-1 results in inappropriate microtubule detachment, defective nuclear envelope reassembly, cytokinesis failure, and aneuploidy [42][43][44]. In addition, OCT1 localizes to mitotic centrosomes following phosphorylation by NEK6 [28]. ...
The genome is dynamically reorganized, partitioned, and divided during mitosis. Despite their role in organizing interphase chromatin, transcription factors were largely believed to be mitotic spectators evicted from chromatin during mitosis, only able to reestablish their position on DNA upon entry into G1. However, a panoply of evidence now contradicts this early belief. Numerous transcription factors are now known to remain active during mitosis to achieve diverse purposes, including chromosome condensation, regulation of the centromere/kinetochore function, and control of centrosome homeostasis. Inactivation of transcription factors during mitosis results in chromosome segregation errors, key features of cancer. Moreover, active transcription and the production of centromere-derived transcripts during mitosis are also known to play key roles in maintaining chromosomal stability. Finally, many transcription factors are associated with chromosomal instability through poorly defined mechanisms. Herein, we will review the emerging roles of transcription factors and transcription during mitosis with a focus on their role in promoting the faithful segregation of sister chromatids.
... Defects on actin filaments organization leading to chromosomal aberrations were detected when breast cancer cells were exposed to prolonged overexpression of YBX1. This genomic instability in pre-malignant cells multiplicates the chance for the production of clones with strong tumorigenic potential [46]. Some reports pointed out the important role of preexisting nonleukemic hematopoietic clones that accumulate mutations and genomic abnormalities during chemotherapy induction and then these clones proliferate and expand causing AML recurrence [47,48]. ...
Background:
Genomic abnormalities were established as prognostic and diagnostic markers for acute myeloid leukemia (AML) tumorgenesis and YBX1 gene has important roles in different cancer types.
Methods:
A total of 109 adult and pediatric patients with De novo AML, were enrolled in this study. Besides the routine lab work; bone marrow YBX1 expression levels were measured using qRT-PCR, and then its possible connections to AML pathogenesis pathway were investigated by STRING tool.
Results:
Results demonstrated upregulation of YBX1 expression level in AML patients that was associated with the presence of adverse genomics abnormalities. In adult patients, the level of YBX1 expression was significantly high in relapsed and resistant groups, while in pediatric patients, the level of YBX1 expression showed an inverse pattern as it was highly expressed in complete remission group. STRING analysis highlighted that YBX1 interacts with important factors in the AML signaling pathway. Kaplan-Meier analysis indicated that adult patients with highly expressed YBX1 significantly endured shorter disease-free survival (DFS) compared to low YBX1 expressers and there was no impact of YBX1 on adult patients overall survival (OS). While pediatric patients with upregulated YBX1 showed good OS over downregulated patients.
Conclusion:
In conclusion, YBX1 may have a crucial role in AML relapse pathogenesis. Also, it could serve as a prognostic factor for AML disease outcomes.
... YB-1 inactivates the p53 pathway to permit continued cellular propagation in spite of genomic insult [56]. In addition to these experimentations, an augmented expression of YB-1 has been demonstrated to cause cell division alterations, damage tolerance, and chemoresistance [57][58][59]. ...
... On the contrary, ectopic production of YB-1 augmented expression of cyclin D1 and cyclin E. However, an effect of an N-terminal 77 amino acid domain of YB-1 has been involved in controlling the progress of the G2/M phases of the cell cycle [62], while inhibition of YB-1 provoked a stop at G2/M [63,64]. Protracted contact of tumor cells to YB-1 provoked cytokinesis malfunction and slippage via the G1/S border [57] (Table 1) ...
The microenvironment of the tumor cells is central to its phenotypic modification. One of the essential elements of this milieu is thermal regulation. An augment in local temperature has been reported to augment the tumor cell's responsiveness to chemo- and radiation treatment. Cold shock proteins are RNA/DNA binding proteins, identified by the existence of one or more cold shock domains. In humans, the best studied components of this group of proteins are called Y-box binding proteins, such as Y-box binding protein-1 (YB-1), but several other proteins have been recognized. Biological functions of these proteins extend from the control of transcription, translation and splicing, to the regulation of exosomal RNA content. Several findings correlate an altered cold shock protein expression profile with tumor diseases. In this review we summarize the data for a causative participation of cold shock proteins in cancer onset and diffusion. Furthermore, the possible use of cold shock proteins for diagnostics, prognosis, and as targets for cancer treatment is exposed.
... In several cancer types, YB-1 has been reported as a promoter of cell proliferation, migration, invasion, and inflammation and as an inhibitor of apoptosis [8][9][10][11]. YB-1 is encoded by the YBX1 gene, performs pleotropic functions, and contains a highly conserved cold shock domain. This domain has an extreme affinity to bind to DNA and RNA [12], which enables YB-1 to regulate the expression of numerous genes, such as the mechanistic target of rapamycin (mTOR), vascular endothelial growth factor (VEGF), signal transducer and activator of transcription 3 (STAT3), nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NF-κB), and major histocompatibility complex class 2 genes (MHC2) and Notch homolog 3 (NOTCH3), which are involved in cell growth and metabolism, angiogenesis, inflammation, immune system evasion, and embryo development, respectively [13][14][15][16]. ...
Cold shock Y-box binding protein-1 (YB-1) coordinates several molecular processes between the nucleus and the cytoplasm and plays a crucial role in cell function. Moreover, it is involved in cancer progression, invasion, and metastasis. As trophoblast cells share similar characteristics with cancer cells, we hypothesized that YB-1 might also be necessary for trophoblast functionality. In samples of patients with intrauterine growth restriction, YB-1 mRNA levels were decreased, while they were increased in preeclampsia and unchanged in spontaneous abortions when compared to normal pregnant controls. Studies with overexpression and downregulation of YB-1 were performed to assess the key trophoblast processes in two trophoblast cell lines HTR8/SVneo and JEG3. Overexpression of YB-1 or exposure of trophoblast cells to recombinant YB-1 caused enhanced proliferation, while knockdown of YB-1 lead to proliferative disadvantage in JEG3 or HTR8/SVneo cells. The invasion and migration properties were affected at different degrees among the trophoblast cell lines. Trophoblast expression of genes mediating migration, invasion, apoptosis, and inflammation was altered upon YB-1 downregulation. Moreover, IL-6 secretion was excessively increased in HTR8/SVneo. Ultimately, YB-1 directly binds to NF-κB enhancer mark in HTR8/SVneo cells. Our data show that YB-1 protein is important for trophoblast cell functioning and, when downregulated, leads to trophoblast disadvantage that at least in part is mediated by NF-κB.
... Upon phosphorylation, YB-1 localized to the centrosome, it complexes with pericentrin and γ-tubulin and maintains the organelle structural integrity. Combined with YB-1-driven cyclin E expression, this led to slippage through the G1/S checkpoint and promoted proliferation of already genetically altered cells [74]. ...
The Y Box binding protein 1 (YB-1) is a member of the highly conserved Cold Shock Domain protein family with multifunctional properties both in the cytoplasm and inside the nucleus. YB-1 is also involved in various cellular functions, including regulation of transcription, mRNA stability, and splicing. Recent studies have associated YB-1 with the regulation of the malignant phenotypes in several tumor types. In this review article, we provide an in-depth and expansive review of the literature pertaining to the multiple physiological functions of YB-1. We will also review the role of YB-1 in cancer development, progression, metastasis, and drug resistance in various malignancies, with more weight on literature published in the last decade. The methodology included querying databases PubMed, Embase, and Google Scholar for Y box binding protein 1, YB-1, YBX1, and Y-box-1.
... Localized translation of axonemal dynein mRNA at the base of the cilia (cellular antenna) is critical for spermatogenesis in drosophila [256]. The centrosomes seem to be an important translational "hub" (Fig. 3, VI): they accumulate various translational components [257][258][259][260] and specific RNAs [130,226,250,255,260,261], although the meaning and significance of such localization are still unclear. It is only known that during cell division, some mRNAs are directed along microtubules into the pericentriole matrix, and then redistributed between daughter cells via actin transport, thus providing asymmetric segregation of transcripts [261]. ...
Spatial organization of protein biosynthesis in the eukaryotic cell has been studied for more than fifty years, thus many facts have already been included in textbooks. According to the classical view, mRNAs encoding secreted and transmembrane proteins are translated by ribosomes associated with endoplasmic reticulum membranes, while soluble cytoplasmic proteins are synthesized on free polysomes. However, in the last few years, new data has emerged, revealing selective translation of mRNA on mitochondria and plastids, in proximity to peroxisomes and endosomes, in various granules and at the cytoskeleton (actin network, vimentin intermediate filaments, microtubules and centrosomes). There are also long-standing debates about the possibility of protein synthesis in the nucleus. Localized translation can be determined by targeting signals in the synthesized protein, nucleotide sequences in the mRNA itself, or both. With RNA-binding proteins, many transcripts can be assembled into specific RNA condensates and form RNP particles, which may be transported by molecular motors to the sites of active translation, form granules and provoke liquid-liquid phase separation in the cytoplasm, both under normal conditions and during cell stress. The translation of some mRNAs occurs in specialized “translation factories,” assemblysomes, transperons and other structures necessary for the correct folding of proteins, interaction with functional partners and formation of oligomeric complexes. Intracellular localization of mRNA has a significant impact on the efficiency of its translation and presumably determines its response to cellular stress. Compartmentalization of mRNAs and the translation machinery also plays an important role in viral infections. Many viruses provoke the formation of specific intracellular structures, virus factories, for the production of their proteins. Here we review the current concepts of the molecular mechanisms of transport, selective localization and local translation of cellular and viral mRNAs, their effects on protein targeting and topogenesis, and on the regulation of protein biosynthesis in different compartments of the eukaryotic cell. Special attention is paid to new systems biology approaches, providing new cues to the study of localized translation.
... Важным трансляционным "хабом" могут быть центросомы (рис. 3, VI): они аккумулируют на себе различные трансляционные компоненты [257][258][259][260] и специфические РНК [130,226,250,255,260,261], хотя смысл и значение такой локализации пока неясны. Известно только, что во время клеточного деления некоторые мРНК направляются по микротрубочкам в прицентриольный матрикс, а затем перераспределяются между дочерними клетками посредством актинового транспорта, обеспечивая таким образом асимметричную сегрегацию транскриптов [261]. ...
Пространственная организация процесса биосинтеза белка в эукариотической клетке изучается вот уже более 50 лет, и многие факты успели войти в учебники. Так, согласно классическим представлениям, мРНК секретируемых и мембранных белков транслируются рибосомами, ассоциированными с мем- бранами эндоплазматического ретикулума, в то время как растворимые белки цитоплазмы синтезируются на свободных полисомах. Однако в последние годы появилось много новых данных об избирательной трансляции мРНК также на митохондриях и пластидах, вблизи пероксисом и эндосом, в различных гра- нулах и на элементах цитоскелета (актиновой сети, виментиновых промежуточных филаментах, микро- трубочках и на центросомах); периодически возобновляются споры о возможности синтеза белка в ядре. Локализованная трансляция может определяться как сигналами адресации в синтезируемом белковом продукте, так и нуклеотидными последовательностями в самой мРНК, а иногда и тем, и другим. Благодаря РНК-связывающим белкам многие транскрипты объединяются в специфичные РНК-конденсаты и фор- мируют РНП-частицы, которые могут транспортироваться по элементам цитоскелета к месту трансляции, образовывать гранулы и провоцировать фазовые переходы участков цитоплазмы – как в нормальных условиях, так и при клеточном стрессе. Трансляция некоторых мРНК происходит в специализированных “трансляционных фабриках”, ассемблисомах, трансперонах и других структурах, необходимых для пра- вильного сворачивания белков, взаимодействия с функциональными партнерами и формирования оли- гомерных комплексов. Внутриклеточная локализация мРНК оказывает существенное влияние на эффек- тивность синтеза белкового продукта и, возможно, определяет характер трансляционного ответа на стрес- совые воздействия. Компартментализация мРНК и трансляционного аппарата играет большую роль также при вирусных инфекциях. Многие вирусы провоцируют формирование специальных внутрикле- точных структур ‒ “вирусных фабрик” ‒ для продукции своих белков. В обзоре рассмотрены сложивши- еся к настоящему моменту представления об избирательной субклеточной локализации клеточных и ви- русных мРНК, о молекулярных механизмах локальной трансляции, ее влиянии на адресацию и топогенез белков и на особенности регуляции биосинтеза белка в разных компартментах эукариотической клетки. Особое внимание уделено современным методам системной биологии, появление которых дало новый импульс изучению локализованной трансляции.
... In 2011, YB-1 was shown to localize to the centrosome in a phosphorylation-dependent manner where it was associated in a complex with pericentrin and g-tubulin [23]. This was found to be essential in maintaining the structural integrity and microtubule nucleation capacity of the organelle. ...
The Y Box binding protein 1 (YB-1) belongs to the highly conserved Cold Shock Domain protein family and is a major component of messenger ribonucleoprotein particles (mRNPs) in various organisms and cells. Cold Shock proteins are multifunctional nucleic acids binding proteins involved in a variety of cellular functions. Biological activities of YB-1 range from the regulation of transcription, splicing and translation, to the orchestration of exosomal RNA content. The role of YB-1 in malignant cell transformation and fate transition is the subject of intensive investigation. Besides, emerging evidence indicates that YB-1 participates in several DNA damage repair pathways as a non-canonical DNA repair factor thus pointing out that the protein can allow cancer cells to evade conventional anticancer therapies and avoid cell death. Here, we will attempt to collect and summarize the current knowledge on this subject and provide the basis for further lines of inquiry.
... YB-1 has also been shown to disable the p53 pathway to allow continued cellular propagation despite genomic insult [19]. In addition to these studies, overexpression of YB-1 has been shown to result in cell division errors [20]. Consistent with damage tolerance, YB-1 also promotes chemotherapy resistance [12,[21][22][23]. ...
... In contrast, a role for an N-terminal 77 amino acid domain of YB-1 has been implicated in regulating progression of the G 2 /M phases of the cell cycle [30] and other studies have demonstrated that inhibiting YB-1 caused an arrest at G 2 /M [31,32]. Furthermore, prolonged exposure of breast cancer cells to YB-1 led to cytokinesis failure and slippage through the G 1 /S border [20]. Thus, it is unclear from these reports whether YB-1 functions in one or more cell cycle phases. ...
... Taken together, these results suggest that YB-1 plays an essential role in facilitating assembly of the microtubules (critical for specification of the cleavage plane) followed by localization of the CPC at the spindle mid-zone. Lack of microtubule assembly in YB-1 depleted cells is consistent with reports in the literature [20,44]. ...
High levels of the cold shock protein Y-box-binding protein-1, YB-1, are tightly correlated with increased cell proliferation and progression. However, the precise mechanism by which YB-1 regulates proliferation is unknown. Here, we found that YB-1 depletion in several cancer cell lines and in immortalized fibroblasts resulted in cytokinesis failure and consequent multinucleation. Rescue experiments indicated that YB-1 was required for completion of cytokinesis. Using confocal imaging we found that YB-1 was essential for orchestrating the spatio-temporal distribution of the microtubules, β-actin and the chromosome passenger complex (CPC) to define the cleavage plane. We show that phosphorylation at six serine residues was essential for cytokinesis, of which novel sites were identified using mass spectrometry. Using atomistic modelling we show how phosphorylation at multiple sites alters YB-1 conformation, allowing it to interact with protein partners. Our results establish phosphorylated YB-1 as a critical regulator of cytokinesis, defining precisely how YB-1 regulates cell division.
... YB-1 has previously been reported to bind to pericentrin and γ-tubulin during mitosis, where it regulates centrosome-based microtubule nucleation and organisation. Notably, over-expression or loss of YB-1 has been previously shown to disrupt the mitotic spindle and cause cytokinesis defects [61][62][63]. Interestingly, all three cell lines saw significant downregulation of several key S-phase and mitotic regulators such as CDC6, H2AX, PLK1, cyclin B2, Aurora B, TACC3, KIF20A and CDC20. ...
Y-box binding protein-1 (YB-1) is a multifunctional oncoprotein that has been shown to regulate proliferation, invasion and metastasis in a variety of cancer types. We previously demonstrated that YB-1 is overexpressed in mesothelioma cells and its knockdown significantly reduces tumour cell proliferation, migration, and invasion. However, the mechanisms driving these effects are unclear. Here, we utilised an unbiased RNA-seq approach to characterise the changes to gene expression caused by loss of YB-1 knockdown in three mesothelioma cell lines (MSTO-211H, VMC23 and REN cells). Bioinformatic analysis showed that YB-1 knockdown regulated 150 common genes that were enriched for regulators of mitosis, integrins and extracellular matrix organisation. However, each cell line also displayed unique gene expression signatures, that were differentially enriched for cell death or cell cycle control. Interestingly, deregulation of STAT3 and p53-pathways were a key differential between each cell line. Using flow cytometry, apoptosis assays and single-cell time-lapse imaging, we confirmed that MSTO-211H, VMC23 and REN cells underwent either increased cell death, G1 arrest or aberrant mitotic division, respectively. In conclusion, this data indicates that YB-1 knockdown affects a core set of genes in mesothelioma cells. Loss of YB-1 causes a cascade of events that leads to reduced mesothelioma proliferation, dependent on the underlying functionality of the STAT3/p53pathways and the genetic landscape of the cell.
