bims-micesi Biomed News
on Mitotic cell signalling
Issue of 2024–10–27
eleven papers selected by
Valentina Piano, Uniklinik Köln
  1. Kinetochore dynein is sufficient to biorient chromosomes and remodel the outer kinetochore.
  2. CENP-C-Mis12 complex establishes a regulatory loop through Aurora B for chromosome segregation.
  3. Golgin45 assists mitosis via its nuclear localization sequence.
  4. Drosophila ring chromosomes interact with sisters and homologs to produce anaphase bridges in mitosis.
  5. Nuclear release of eIF1 restricts start-codon selection during mitosis.
  6. Mutation of the SUMOylation site of Aurora-B disrupts spindle formation and chromosome alignment in oocytes.
  7. Genetically Encoded Fluorescence Resonance Energy Transfer Biosensor for Live-Cell Visualization of Lamin A Phosphorylation at Serine 22.
  8. ERMCS Ca2+ transmission fuels cell division.
  9. Protocol for validating liquid-liquid phase separation as a driver of membraneless organelle assembly in vitro and in human cells.
  10. A protein phosphatase 1 specific phosphatase targeting peptide (PhosTAP) to identify the PP1 phosphatome.
  11. Unleashing the Power of Cold Atmospheric Plasma: Inducing Mitochondria Damage-Mediated Mitotic Catastrophe.
  1. Nat Commun. 2024 Oct 21. 15(1): 9085
    Kinetochore dynein is sufficient to biorient chromosomes and remodel the outer kinetochore.
    Bram Prevo, Dhanya K Cheerambathur, William C Earnshaw, Arshad Desai.
      Multiple microtubule-directed activities concentrate on mitotic chromosomes to ensure their faithful segregation. These include couplers and dynamics regulators localized at the kinetochore, the microtubule interface built on centromeric chromatin, as well as motor proteins recruited to kinetochores and chromatin. Here, we describe an in vivo approach in the C. elegans one-cell embryo in which removal of the major microtubule-directed activities on mitotic chromosomes is compared to the selective presence of individual activities. Our approach reveals that the kinetochore dynein module, comprised of cytoplasmic dynein and its kinetochore-specific adapters, is sufficient to biorient chromosomes; by contrast, this module is unable to support congression. In coordination with orientation, the dynein module directs removal of outermost kinetochore components, including dynein itself, independently of the other microtubule-directed activities and kinetochore-localized protein phosphatase 1. These observations indicate that the kinetochore dynein module is sufficient to biorient chromosomes and to direct remodeling of the outer kinetochore in a microtubule attachment state-sensitive manner.
    DOI:  https://doi.org/10.1038/s41467-024-52964-5
  2. Life Sci Alliance. 2025 Jan;pii: e202402927. [Epub ahead of print]8(1):
    CENP-C-Mis12 complex establishes a regulatory loop through Aurora B for chromosome segregation.
    Weixia Kong, Masatoshi Hara, Yurika Tokunaga, Kazuhiro Okumura, Yasuhiro Hirano, Jiahang Miao, Yusuke Takenoshita, Masakazu Hashimoto, Hiroshi Sasaki, Toshihiko Fujimori, Yuichi Wakabayashi, Tatsuo Fukagawa.
      Establishing the correct kinetochore-microtubule attachment is crucial for faithful chromosome segregation. The kinetochore has various regulatory mechanisms for establishing correct bipolar attachment. However, how the regulations are coupled is not fully understood. Here, we demonstrate a regulatory loop between the kinetochore protein CENP-C and Aurora B kinase, which is critical for the error correction of kinetochore-microtubule attachment. This regulatory loop is mediated through the binding of CENP-C to the outer kinetochore Mis12 complex (Mis12C). Although the Mis12C-binding region of CENP-C is dispensable for mouse development and proliferation in human RPE-1 cells, those cells lacking this region display increased mitotic defects. The CENP-C-Mis12C interaction facilitates the centromeric recruitment of Aurora B and the mitotic error correction in human cells. Given that Aurora B reinforces the CENP-C-Mis12C interaction, our findings reveal a positive regulatory loop between Aurora B recruitment and the CENP-C-Mis12C interaction, which ensures chromosome biorientation for accurate chromosome segregation.
    DOI:  https://doi.org/10.26508/lsa.202402927
  3. Biochem Biophys Res Commun. 2024 Oct 17. pii: S0006-291X(24)01381-0. [Epub ahead of print]735 150845
    Golgin45 assists mitosis via its nuclear localization sequence.
    Jingkai Gao, Lianhui Zhu, Xihua Yue, Shuaiyang Jing, Shuocheng Tang, Intaek Lee, Yi Qian.
      In mammalian cells, the Golgi apparatus undergoes fragmentation for its correct partition into two daughter cells during mitosis. Several Golgi structural proteins have been demonstrated to regulate Golgi disassembly/reassembly and spindle formation. However, it is largely unknown whether Golgi proteins mediate other major events in mitosis. Here, we report that Golgin45, a Golgi tethering protein, participates in recruiting PLK1 to the kinetochores. Upon entry into mitosis, Golgin45 binds PLK1 and a nuclear import protein, importin β2. Enriched RanGTP at kinetochores in prometaphase and metaphase sequesters importin β2 from Golgin45 and liberates Golgin45-PLK1 complex, which then gets further delivered to the kinetochores by Golgin45-KNL1 interaction. R375A mutation in Golgin45 that specifically disrupts Golgin45-importin β2 interaction impairs PLK1 localization to the kinetochores, leading to mitotic arrest. Our findings reveal a novel role of a golgin tether protein in mediating Ran-dependent PLK1 enrichment on the kinetochores for proper progression of mitosis.
    Keywords:  GRASP55; Golgi; Golgin45; Importin β2; KNL1; Kinetochore; Mitosis; PLK1
    DOI:  https://doi.org/10.1016/j.bbrc.2024.150845
  4. Genetics. 2024 Oct 25. pii: iyae169. [Epub ahead of print]
    Drosophila ring chromosomes interact with sisters and homologs to produce anaphase bridges in mitosis.
    Ho-Chen Lin, Mary M Golic, Hunter J Hill, Katherine F Lemons, Truc T Vuong, Madison Smith, Forrest Golic, Kent G Golic.
      Ring chromosomes are known in many eukaryotic organisms, including humans. They are typically associated with a variety of maladies, including abnormal development and lethality. Underlying these phenotypes are anaphase chromatin bridges that can lead to chromosome loss, nondisjunction and breakage. By cytological examination of ring chromosomes in Drosophila melanogaster we identified five causes for anaphase bridges produced by ring chromosomes. Catenation of sister chromatids appears to be the most common cause and these bridges frequently resolve during anaphase, presumably by the action of topoisomerase II. Sister chromatid exchange and chromosome breakage followed by sister chromatid union also produce anaphase bridges. Mitotic recombination with the homolog was rare, but was another route to generation of anaphase bridges. Most surprising, was the discovery of homolog capture, where the ring chromosome was connected to its linear homolog in anaphase. We hypothesize that this is a remnant of mitotic pairing and that the linear chromosome is connected to the ring by multiple wraps produced through the action of topoisomerase II during establishment of homolog pairing. In support, we showed that in a ring/ring homozygote the two rings are frequently catenated in mitotic metaphase, a configuration that requires breaking and rejoining of at least one chromosome.
    Keywords:  anaphase bridge; chromosome breakage; mitosis; mitotic pairing; ring chromosome; sister chromatid exchange; somatic pairing; topoisomerase II
    DOI:  https://doi.org/10.1093/genetics/iyae169
  5. Nature. 2024 Oct 23.
    Nuclear release of eIF1 restricts start-codon selection during mitosis.
    Jimmy Ly, Kehui Xiang, Kuan-Chung Su, Gunter B Sissoko, David P Bartel, Iain M Cheeseman.
      Regulated start-codon selection has the potential to reshape the proteome through the differential production of upstream open reading frames, canonical proteins, and alternative translational isoforms1-3. However, conditions under which start codon selection is altered remain poorly defined. Here, using transcriptome-wide translation-initiation-site profiling4, we reveal a global increase in the stringency of start-codon selection during mammalian mitosis. Low-efficiency initiation sites are preferentially repressed in mitosis, resulting in pervasive changes in the translation of thousands of start sites and their corresponding protein products. This enhanced stringency of start-codon selection during mitosis results from increased association between the 40S ribosome and the key regulator of start-codon selection, eIF1. We find that increased eIF1-40S ribosome interaction during mitosis is mediated by the release of a nuclear pool of eIF1 upon nuclear envelope breakdown. Selectively depleting the nuclear pool of eIF1 eliminates the change to translational stringency during mitosis, resulting in altered synthesis of thousands of protein isoforms. In addition, preventing mitotic translational rewiring results in substantially increased cell death and decreased mitotic slippage in cells that experience a mitotic delay induced by anti-mitotic chemotherapies. Thus, cells globally control stringency of translation initiation, which has critical roles during the mammalian cell cycle in preserving mitotic cell physiology.
    DOI:  https://doi.org/10.1038/s41586-024-08088-3
  6. Cell Death Discov. 2024 Oct 22. 10(1): 447
    Mutation of the SUMOylation site of Aurora-B disrupts spindle formation and chromosome alignment in oocytes.
    Shan-Shan Chen, Li Li, Bo Yao, Jia-Lun Guo, Ping-Shuang Lu, Hao-Lin Zhang, Kun-Huan Zhang, Yuan-Jing Zou, Nan-Jian Luo, Shao-Chen Sun, Lin-Lin Hu, Yan-Ping Ren.
      Aurora-B is a kinase that regulates spindle assembly and kinetochore-microtubule (KT-MT) attachment during mitosis and meiosis. SUMOylation is involved in the oocyte meiosis regulation through promoting spindle assembly and chromosome segregation, but its substrates to support this function is still unknown. It is reported that Aurora-B is SUMOylated in somatic cells, and SUMOylated Aurora-B contributes the process of mitosis. However, whether Aurora-B is SUMOylated in oocytes and how SUMOylation of Aurora-B impacts its function in oocyte meiosis remain poorly understood. In this study, we report that Aurora-B is modified by SUMOylation in mouse oocytes. The results show that Aurora-B colocalized and interacted with SUMO-2/3 in mouse oocytes, confirming that Aurora-B is modified by SUMO-2/3 in this system. Compared with that in young mice, the protein expression of SUMO-2/3 decreased in the oocytes of aged mice, indicating that SUMOylation might be related to mouse aging. Overexpression of Aurora-B SUMOylation site mutants, Aurora-BK207R and Aurora-BK292R, inhibited Aurora-B recruitment and first polar body extrusion, disrupting localization of gamma tubulin, spindle formation and chromosome alignment in oocytes. The results show that it was related to decreased recruitment of p-HDAC6 which induces the high stability of whole spindle microtubules including the microtubules of both correct and wrong KT-MT attachments though increased acetylation of microtubules. Therefore, our results corroborate the notion that Aurora-B activity is regulated by SUMO-2/3 in oocytes, and that SUMOylated Aurora B plays an important role in spindle formation and chromosome alignment.
    DOI:  https://doi.org/10.1038/s41420-024-02217-7
  7. Biomater Res. 2024 ;28 0091
    Genetically Encoded Fluorescence Resonance Energy Transfer Biosensor for Live-Cell Visualization of Lamin A Phosphorylation at Serine 22.
    Jian Liu, Qianqian Li, Jinfeng Wang, Juhui Qiu, Jing Zhou, Qin Peng.
      Extensive phosphorylation at serine 22 (pSer22) on lamin A is the hallmark of cell mitosis, which contributes to the breakdown of nuclear envelope. In the interphase, pSer22 lamin A exists in low abundance and is involved in mechanotransduction, virus infection, and gene expression. Numerous evidences emerge to support lamin A regulation on cell function and fate by phosphorylation. However, live-cell imaging tools for visualizing the dynamics of pSer22 lamin A are yet to be established. Herein, we developed a novel lamin A phosphorylation sensor (LAPS) based on fluorescence resonance energy transfer (FRET) with high sensitivity and specificity. We observed the dynamic lamin A phosphorylation during the cell cycle progression in single living cells: the increase of pSer22 modification when cells entered the mitosis and recovered upon the mitosis exit. Our biosensor also showed the gradual reduction of pSer22 modification during cell adhesion and in response to hypotonic environment. By applying LAPS, we captured the propagation of pSer22 modification from inside to outside of the inner nuclear membrane, which further led to the breakdown of nuclear envelope. Meanwhile, we found the synchronous phosphorylation of pSer22 lamin A and H3S10ph at mitosis entry. Inhibition of Aurora B, the responsible kinase for H3S10ph, could shorten the mitotic period without obvious effect on the pSer22 modification level of lamin A. Thus, LAPS allows the spatiotemporal visualization of the lamin A pSer22, which will be useful for elucidating the molecular mechanisms underlying cell mitosis and mechanoresponsive processes.
    DOI:  https://doi.org/10.34133/bmr.0091
  8. Trends Cell Biol. 2024 Oct 21. pii: S0962-8924(24)00208-3. [Epub ahead of print]
    ERMCS Ca2+ transmission fuels cell division.
    Muniswamy Madesh, Neelanjan Vishnu, Dhanendra Tomar.
      Mitosis is a cellular process that demands high energy, but it was previously unclear how this process is linked with mitochondrial ATP production. Zhao et al. describe how during mitosis, the lamin B receptor migrates to the ER membrane to enhance ER-mitochondria contact sites, coordinating Ca2+ surges that increase ATP production necessary for cell division.
    DOI:  https://doi.org/10.1016/j.tcb.2024.10.002
  9. STAR Protoc. 2024 Oct 23. pii: S2666-1667(24)00575-6. [Epub ahead of print]5(4): 103410
    Protocol for validating liquid-liquid phase separation as a driver of membraneless organelle assembly in vitro and in human cells.
    Marius Hedtfeld, Andrea Musacchio.
      Liquid-liquid phase separation (LLPS) of scaffold proteins has often been proposed to drive the biogenesis of membraneless cellular compartments. Here, we present a protocol to link in vitro LLPS propensity to localization in vivo. We describe steps for examining LLPS in vitro in the presence of crowding agents or cytomimetic media. We complement our in vitro studies with recombinant proteins with experiments of protein electroporation into mitotic HeLa cells. In addition, we discuss steps to assess protein localization and delivery levels. For complete details on the use and execution of this protocol, please refer to Hedtfeld et al.1.
    Keywords:  Cell Biology; Protein Biochemistry; Protein expression and purification
    DOI:  https://doi.org/10.1016/j.xpro.2024.103410
  10. Proc Natl Acad Sci U S A. 2024 Oct 29. 121(44): e2415383121
    A protein phosphatase 1 specific phosphatase targeting peptide (PhosTAP) to identify the PP1 phosphatome.
    Meng S Choy, Hieu T Nguyen, Ganesan S Kumar, Wolfgang Peti, Arminja N Kettenbach, Rebecca Page.
      Phosphoprotein phosphatases (PPPs) are the key serine/threonine phosphatases that regulate all essential signaling cascades. In particular, Protein Phosphatase 1 (PP1) dephosphorylates ~80% of all ser/thr phosphorylation sites. Here, we developed a phosphatase targeting peptide (PhosTAP) that binds all PP1 isoforms and does so with a stronger affinity than any other known PP1 regulator. This PhosTAP can be used as a PP1 recruitment tool for Phosphorylation Targeting Chimera (PhosTAC)-type recruitment in in vitro and cellular experiments, as well as in phosphoproteomics experiments to identify PP1-specific substrates and phosphosites. The latter is especially important to further our understanding of cellular signaling, as the identification of substrates and especially phosphosites that are targeted by specific phosphatases lags behind that of their kinase counterparts. Using PhosTAP-based proteomics, we show that, counter to our current understanding, many PP1 regulators are also substrates, that the number of residues between regulator PP1-binding and phosphosites vary significantly, and that PP1 counteracts the activities of mitotic kinases. Finally, we also found that Haspin kinase is a direct substrate of PP1 and that its PP1-dependent dephosphorylation modulates its activity during anaphase. Together, we show that PP1-specific PhosTAPs are a powerful tool for +studying PP1 activity in vitro and in cells.
    Keywords:  phosphatase targeting peptide (PhosTAP); phosphoprotein phosphatases (PPP); protein engineering; protein phosphatase 1 (PP1); protein–protein interactions
    DOI:  https://doi.org/10.1073/pnas.2415383121
  11. Adv Sci (Weinh). 2024 Oct 23. e2401842
    Unleashing the Power of Cold Atmospheric Plasma: Inducing Mitochondria Damage-Mediated Mitotic Catastrophe.
    Shengjie Peng, Yue Feng, K N Yu, Lijun Wu, Guodong Chen, Miaomiao Yang, Lele Zhao, Wei Cao, Qianwen Cui, Lianjun Chen, Quan Li, Yifan Huang, Cheng Cheng, Fengqin Zhu, Wei Han.
      Despite the promise of cold atmospheric plasma (CAP) for cancer treatment, the challenges associated with the treatment of solid tumors and penetration depth limitations remain, restricting its clinical application. Here, biological evidence is provided that the killing effect of CAP treatment is confined to less than 500 µm subcutaneously and the actual biological dose decreased gradually with depth for the first time, indicating that the limited penetration depth has become an urgent problem that demands immediate solutions. Significantly, it is showed that different from high-dose treatments, CAP decreased the doses to the low-dose range but still exhibited anti-tumor effects via mitotic catastrophe. Unlike radiotherapy or chemotherapy, low-dose CAP treatment induces mitochondrial structural damage and dysfunction, disrupts energy metabolism and redox balance, and results in mitotic catastrophe. Collectively, these findings suggest that better understanding and taking full advantage of the dose-response gradient effect of CAP is a potential strategy to prompt its clinical application beyond improving CAP penetration.
    Keywords:  anti‐tumor effect; cold atmospheric plasma; mitochondria damage; mitotic catastrophe
    DOI:  https://doi.org/10.1002/advs.202401842
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