Similar Datasets
Project description:Aurora B kinase, as part of the chromosomal passenger complex (CPC), controls key processes during the cell cycle such as DNA compaction, genome partitioning or cytokinesis. Nonetheless, increased Aurora B levels are a potential threat for the cells and have been linked to different tumor types. We have carried out an exhaustive characterization of the global consequences of the overexpression of Aurora B and INCENP, the scaffold of the CPC and an activator of Aurora B kinase activity, in non-transformed human cells. Our data demonstrate, not only that an individual increase in the levels of Aurora B or INCENP have a different impact on the cells, but more importantly that their simultaneous overexpression stabilizes both CPC components, exacerbates Aurora B activity, severely impairs mitotic progression and chromosome dynamics, and has a distinctive and more dramatic effect on the transcriptional landscape of the cells.
2025-05-06 | GSE273668 | GEO
Project description:Aurora B kinase, as part of the chromosomal passenger complex (CPC), controls key processes during the cell cycle such as DNA compaction, genome partitioning or cytokinesis. Nonetheless, increased Aurora B levels are a potential threat for the cells and have been linked to different tumor types. We have carried out an exhaustive characterization of the global consequences of the overexpression of Aurora B and INCENP, the scaffold of the CPC and an activator of Aurora B kinase activity, in non-transformed human cells. Our data demonstrate, not only that an individual increase in the levels of Aurora B or INCENP have a different impact on the cells, but more importantly that their simultaneous overexpression stabilizes both CPC components, exacerbates Aurora B activity, severely impairs mitotic progression and chromosome dynamics, and has a distinctive and more dramatic effect on the transcriptional landscape of the cells.
2025-05-06 | GSE273663 | GEO
Project description:Aurora B and INCENP co-overexpression severely disrupts mitosis and distinctly modifies the global transcriptional landscape
| PRJNA1142593 | ENA
Project description:Aurora B and INCENP co-overexpression severely disrupts mitosis and distinctly modifies the global transcriptional landscape [RNA-seq]
| PRJNA1142588 | ENA
Project description:Aurora B and INCENP co-overexpression severely disrupts mitosis and distinctly modifies the global transcriptional landscape [ChIP-seq]
| PRJNA1142597 | ENA
Project description:The mitotic spindle is made of microtubules (MTs) nucleated through different pathways involving the centrosomes, the chromosomes or the walls of pre-existing MTs. MCRS1 is a RanGTP target that specifically associates with the chromosome-driven MTs protecting them from MT depolymerases. MCRS1 is also needed for the control of kinetochore fiber (K-fiber) MT minus-ends dynamics in metaphase. Here, we investigated the regulation of MCRS1 activity in M-phase. We show that MCRS1 is phosphorylated by the Aurora-A kinase in mitosis on Ser35/36. Although this phosphorylation has no role on MCRS1 localization to chromosomal MTs and K-fiber minus-ends, we show that it regulates MCRS1 activity in mitosis. We conclude that Aurora-A activity is particularly important in the tuning of K-fiber minus-ends dynamics in mitosis.
| S-EPMC4957591 | biostudies-literature
Project description:Protein phase separation or coacervation has emerged as a potential mechanism to regulate biological functions. We have shown that coacervation of a mostly unstructured protein, BuGZ, promotes assembly of spindle and its matrix. BuGZ in the spindle matrix binds and concentrates tubulin to promote microtubule (MT) assembly. It remains unclear, however, whether BuGZ could regulate additional proteins to promote spindle assembly. In this study, we report that BuGZ promotes Aurora A (AurA) activation in vitro. Depletion of BuGZ in cells reduces the amount of phosphorylated AurA on spindle MTs. BuGZ also enhances MCAK phosphorylation. The two zinc fingers in BuGZ directly bind to the kinase domain of AurA, which allows AurA to incorporate into the coacervates formed by BuGZ in vitro. Importantly, mutant BuGZ that disrupts the coacervation activity in vitro fails to promote AurA phosphorylation in Xenopus laevis egg extracts. These results suggest that BuGZ coacervation promotes AurA activation in mitosis.
| S-EPMC5748987 | biostudies-literature
Project description:Accurate chromosome segregation is essential for cell viability. The mitotic spindle is crucial for chromosome segregation, but much remains unknown about factors that regulate spindle assembly. Recent work implicates RNA in promoting proper spindle assembly independently of mRNA translation; however, the mechanism by which RNA performs this function is currently unknown. Here, we show that RNA regulates both the localization and catalytic activity of the mitotic kinase, Aurora-B (AurB), which is present in a ribonucleoprotein (RNP) complex with many mRNAs. Interestingly, AurB kinase activity is reduced in Xenopus egg extracts treated with RNase, and its activity is stimulated in vitro by RNA binding. Spindle assembly defects following RNase-treatment are partially rescued by inhibiting MCAK, a microtubule depolymerase that is inactivated by AurB-dependent phosphorylation. These findings implicate AurB as an important RNA-dependent spindle assembly factor, and demonstrate a translation-independent role for RNA in stimulating AurB.
| S-EPMC4072698 | biostudies-literature
Project description:Cell cycle-dependent redox changes can mediate transient covalent modifications of cysteine thiols to modulate the activities of regulatory kinases and phosphatases. Our previously reported finding that protein cysteine oxidation is increased during mitosis relative to other cell cycle phases suggests that redox modifications could play prominent roles in regulating mitotic processes. The Aurora family of kinases and their downstream targets are key components of the cellular machinery that ensures the proper execution of mitosis and the accurate segregation of chromosomes to daughter cells. In this study, x-ray crystal structures of the Aurora A kinase domain delineate redox-sensitive cysteine residues that, upon covalent modification, can allosterically regulate kinase activity and oligomerization state. We showed in both Xenopus laevis egg extracts and mammalian cells that a conserved cysteine residue within the Aurora A activation loop is crucial for Aurora A activation by autophosphorylation. We further showed that covalent disulfide adducts of this residue promote autophosphorylation of the Aurora A kinase domain. These findings reveal a potential mechanistic link between Aurora A activation and changes in the intracellular redox state during mitosis and provide insights into how novel small-molecule inhibitors may be developed to target specific subpopulations of Aurora A.
| S-EPMC8514121 | biostudies-literature
Project description:Entry into mitosis is a highly regulated process, promoted by the activated Cyclin B1/Cdk1 complex. Activation of this complex is controlled, in part, by the protein kinase Aurora-A, which is a member of a multigenic serine/threonine kinase family. In normal cells, Aurora-A activity is regulated, at least in part, by degradation through the APC-ubiquitin-proteasome pathway. It has recently been proposed that, in Xenopus, Aurora-A degradation can be inhibited by phosphorylation. It would thus be expected that a phosphatase activity would release this blockade at the end of mitosis. Here, we have shown that the protein phosphatase PP2A and Aurora-A are colocalized at the cell poles during mitosis in human cells and interact within the same complex. Using the PP2A inhibitor okadaic acid and an RNAi approach, we have shown that this interaction is functional within the cell. PP2A/Aurora-A interaction is promoted by an S51D mutation in Aurora-A and inhibited by a phosphomimetic peptide centered around Aurora-A S51, thereby strongly suggesting that PP2A controls Aurora-A degradation by dephosphorylating serine 51 in the A box of the human enzyme.
| S-EPMC1839003 | biostudies-literature