bims-micesi 2022-05-29 papers

bims-micesi

Biomed News

on Mitotic cell signalling

Issue of 2022–05–29
twelve papers selected by
Valentina Piano, Max Planck Institute of Molecular Physiology

Ginsenoside Rg1 suppresses cancer cell proliferation through perturbing mitotic progression.
Preprint Highlight: Interphase microtubule disassembly is a signaling cue that drives cell rounding at mitotic entry.
BUB3, beyond the Simple Role of Partner.
Inhibition of Polo-like Kinase 1 by HMN-214 Blocks Cell Cycle Progression and Inhibits Neuroblastoma Growth.
MEL-28/ELYS and CENP-C coordinately control outer kinetochore assembly and meiotic chromosome-microtubule interactions.
Chromosome organization through the cell cycle at a glance.
Vibrio cholerae Chromosome Partitioning without Polar Anchoring by HubP.
Pericentriolar matrix (PCM) integrity relies on cenexin and Polo-Like Kinase (PLK)1.
Generation of dynamic three-dimensional genome structure through phase separation of chromatin.
SRC Kinase-Mediated Tyrosine Phosphorylation of TUBB3 Regulates Its Stability and Mitotic Spindle Dynamics in Prostate Cancer Cells.
Alternative end-joining originates stable chromosome aberrations induced by etoposide during targeted inhibition of DNA-PKcs in ATM-deficient tumor cells.
Transcription Factor NRF2 Participates in Cell Cycle Progression at the Level of G1/S and Mitotic Checkpoints.

J Ginseng Res. 2022 May;46(3): 481-488

Ginsenoside Rg1 suppresses cancer cell proliferation through perturbing mitotic progression.

Jihee Hong, Dasom Gwon, Chang-Young Jang.

   Background: Although the tumor-suppressive effects of ginsenosides in cell cycle have been well established, their pharmacological properties in mitosis have not been clarified yet. The chromosomal instability resulting from dysregulated mitotic processes is usually increased in cancer. In this study, we aimed to investigate the anticancer effects of ginsenoside Rg1 on mitotic progression in cancer.
Materials and methods: Cancer cells were treated with ginsenoside Rg1 and their morphology and intensity of different protein were analyzed using immunofluorescence microscopy. The level of proteins in chromosomes was compared through chromosomal fractionation and Western blot analyses. The location and intensity of proteins in the chromosome were confirmed through immunostaining of mitotic chromosome after spreading. The colony formation assays were conducted using various cancer cell lines.
Results: Ginsenoside Rg1 reduced cancer cell proliferation in some cancers through inducing mitotic arrest. Mechanistically, it inhibits the phosphorylation of histone H3 Thr3 (H3T3ph) mediated by Haspin kinase and concomitant recruitment of chromosomal passenger complex (CPC) to the centromere. Depletion of Aurora B at the centromere led to abnormal centromere integrity and spindle dynamics, thereby causing mitotic defects, such as increase in the width of the metaphase plate and spindle instability, resulting in delayed mitotic progression and cancer cell proliferation.
Conclusion: Ginsenoside Rg1 reduces the level of Aurora B at the centromere via perturbing Haspin kinase activity and concurrent H3T3ph. Therefore, ginsenoside Rg1 suppresses cancer cell proliferation through impeding mitotic processes, such as chromosome alignment and spindle dynamics, upon depletion of Aurora B from the centromere.

Keywords:  Aurora B; Cancer; Ginsenoside Rg1; Haspin kinase; Mitosis

DOI:  https://doi.org/10.1016/j.jgr.2021.11.004
Mol Biol Cell. 2022 Jun 01. 33(7): mbcP22031005

Preprint Highlight: Interphase microtubule disassembly is a signaling cue that drives cell rounding at mitotic entry.

Jennifer Landino.

DOI: https://doi.org/10.1091/mbc.P22-03-1005
Pharmaceutics. 2022 May 18. pii: 1084. [Epub ahead of print]14(5):

BUB3, beyond the Simple Role of Partner.

Patrícia M A Silva, Hassan Bousbaa.

  The BUB3 protein plays a key role in the activation of the spindle assembly checkpoint (SAC), a ubiquitous surveillance mechanism that ensures the fidelity of chromosome segregation in mitosis and, consequently, prevents chromosome mis-segregation and aneuploidy. Besides its role in SAC signaling, BUB3 regulates chromosome attachment to the spindle microtubules. It is also involved in telomere replication and maintenance. Deficiency of the BUB3 gene has been closely linked to premature aging. Upregulation of the BUB3 gene has been found in a variety of human cancers and is associated with poor prognoses. Here, we review the structure and functions of BUB3 in mitosis, its expression in cancer and association with survival prognoses, and its potential as an anticancer target.

Keywords:  BUB3; anticancer target; cancer; mitosis; senescence; spindle assembly checkpoint

DOI:  https://doi.org/10.3390/pharmaceutics14051084
Pharmaceuticals (Basel). 2022 Apr 24. pii: 523. [Epub ahead of print]15(5):

Inhibition of Polo-like Kinase 1 by HMN-214 Blocks Cell Cycle Progression and Inhibits Neuroblastoma Growth.

Rameswari Chilamakuri, Danielle Crystal Rouse, Saurabh Agarwal.

  Polo-like kinase 1 (PLK1) is an essential cell cycle mitotic kinase component that plays an important role in cell cycle progression and has been reported to be involved in various cancers, including neuroblastoma (NB). PLK1 also regulates G2/M transition, chromosomal segregation, spindle assembly maturation, and mitotic exit. NB is an early embryonic-stage heterogeneous solid tumor and accounts for 15% of all pediatric cancer-related deaths. Therefore, we aimed to develop a targeting strategy for PLK1 by repurposing HMN-214 in NB. HMN-214 is a prodrug of HMN-176 and is known to selectively interfere with PLK1 function. In the present study, we performed the transcriptomic analysis of a large cohort of primary NB patient samples and revealed that PLK1 expression is inversely correlated with the overall survival of NB patients. Additionally, we found that PLK1 strongly correlates with NB disease and stage progression. HMN-214 significantly inhibited NB proliferation and colony formation in both MYCN-amplified and -nonamplified cell lines in a dose-dependent manner. Furthermore, HMN-214 induces apoptosis and significantly obstructs the cell cycle at the G2/M phase in NB cells by inhibiting multiple cell-cycle-related genes, such as PLK1, WEE1, CDK1, CDK2, Cyclin B1, CHK1, and CHK2. HMN-214 significantly inhibits cell cycle regulator CDK1 and the phosphorylation and activation of PLK1 in NB. In the NB 3D spheroid tumor model, HMN-214 significantly and in a dose-dependent manner inhibits spheroid tumor mass and growth. Overall, our study highlights that targeting PLK1 using HMN-214 is a novel therapeutic approach for NB.

Keywords:  HMN-214; PLK1; cell cycle; neuroblastoma; pediatric cancer

DOI:  https://doi.org/10.3390/ph15050523
Curr Biol. 2022 May 18. pii: S0960-9822(22)00664-9. [Epub ahead of print]

MEL-28/ELYS and CENP-C coordinately control outer kinetochore assembly and meiotic chromosome-microtubule interactions.

Neil Hattersley, Aleesa J Schlientz, Bram Prevo, Karen Oegema, Arshad Desai.

  During mitosis and meiosis in the majority of eukaryotes, centromeric chromatin comprised of CENP-A nucleosomes and their reader CENP-C recruits components of the outer kinetochore to build an interface with spindle microtubules.1,2 One exception is C. elegans oocyte meiosis, where outer kinetochore proteins form cup-like structures on chromosomes independently of centromeric chromatin.3 Here, we show that the nucleoporin MEL-28 (ortholog of human ELYS) and CENP-CHCP-4 act in parallel to recruit outer kinetochore components to oocyte meiotic chromosomes. Unexpectedly, co-inhibition of MEL-28 and CENP-CHCP-4 resulted in chromosomes being expelled from the meiotic spindle prior to anaphase onset, a more severe phenotype than what was observed following ablation of the outer kinetochore.4,5 This observation suggested that MEL-28 and the outer kinetochore independently link chromosomes to spindle microtubules. Consistent with this, the chromosome expulsion defect was observed following co-inhibition of MEL-28 and the microtubule-coupling KNL-1/MIS-12/NDC-80 (KMN) network of the outer kinetochore. Use of engineered mutants showed that MEL-28 acts in conjunction with the microtubule-binding NDC-80 complex to keep chromosomes within the oocyte meiotic spindle and that this function likely involves the Y-complex of nucleoporins that associate with MEL-28; by contrast, the ability to dock protein phosphatase 1, shared by MEL-28 and KNL-1, is not involved. These results highlight nuclear pore-independent functions for a conserved nucleoporin and explain two unusual features of oocyte meiotic chromosome segregation in C. elegans: centromeric chromatin-independent outer kinetochore assembly, and dispensability of the outer kinetochore for constraining chromosomes in the acentrosomal meiotic spindle.

Keywords:  C. elegans; CENPA; CENPC; ELYS; KMN network; NDC80; centromere; kinetochore; meiosis; nuclear pore; oocyte; spindle

DOI:  https://doi.org/10.1016/j.cub.2022.04.046
J Cell Sci. 2022 May 15. pii: jcs244004. [Epub ahead of print]135(10):

Chromosome organization through the cell cycle at a glance.

Divyaa Srinivasan, Tarak Shisode, Jatin Shrinet, Peter Fraser.

  Genome organization and the three-dimensional folding of chromosomes are now seen as major contributors to nearly all nuclear functions including gene regulation, replication and repair. Recent studies have shown that in addition to the dramatic metamorphoses in chromosome conformation associated with entry to, and exit from mitosis, chromosomes undergo continual conformational changes throughout interphase with differential dynamics in loop structure, topological domains, compartments and lamina-associated domains. Understanding and accounting for these cell-cycle-dependent conformational changes is essential for the interpretation of data from a growing array of powerful molecular techniques to investigate genome conformation function, and to identify the molecules and mechanisms that drive chromosome conformational changes. In this Cell Science at a Glance article and the accompanying poster, we review Hi-C and microscopy studies describing cell-cycle-dependent conformational changes in chromosome structure.

Keywords:  Cell cycle; Chromatin folding; Nuclear genome organization

DOI:  https://doi.org/10.1242/jcs.244004
Genes (Basel). 2022 May 13. pii: 877. [Epub ahead of print]13(5):

Vibrio cholerae Chromosome Partitioning without Polar Anchoring by HubP.

Christophe Possoz, Yoshiharu Yamaichi, Elisa Galli, Jean-Luc Ferat, Francois-Xavier Barre.

  Partition systems are widespread among bacterial chromosomes. They are composed of two effectors, ParA and ParB, and cis acting sites, parS, located close to the replication origin of the chromosome (oriC). ParABS participate in chromosome segregation, at least in part because they serve to properly position sister copies of oriC. A fourth element, located at cell poles, is also involved in some cases, such as HubP for the ParABS1 system of Vibrio cholerae chromosome 1 (ch1). The polar anchoring of oriC of ch1 (oriC1) is lost when HubP or ParABS1 are inactivated. Here, we report that in the absence of HubP, ParABS1 actively maintains oriC1 at mid-cell, leading to the subcellular separation of the two ch1 replication arms. We further show that parS1 sites ectopically inserted in chromosome 2 (ch2) stabilize the inheritance of this replicon in the absence of its endogenous partition system, even without HubP. We also observe the positioning interference between oriC1 and oriC of ch2 regions when their positionings are both driven by ParABS1. Altogether, these data indicate that ParABS1 remains functional in the absence of HubP, which raises questions about the role of the polar anchoring of oriC1 in the cell cycle.

Keywords:  HubP; ParABS; Vibrio cholerae; chromosome organization; chromosome segregation; partition system

DOI:  https://doi.org/10.3390/genes13050877
Mol Biol Cell. 2022 May 24. mbcE22010015

Pericentriolar matrix (PCM) integrity relies on cenexin and Polo-Like Kinase (PLK)1.

Abrar Aljiboury, Amra Mujcic, Erin Curtis, Thomas Cammerino, Denise Magny, Yiling Lan, Michael Bates, Judy Freshour, Yasir H Ahmed-Braimeh, Heidi Hehnly.

Polo-Like-Kinase (PLK) 1 activity is associated with maintaining the functional and physical properties of the centrosome's pericentriolar matrix (PCM). In this study, we use a multimodal approach of human cells (HeLa), zebrafish embryos, and phylogenic analysis to test the role of a PLK1 binding protein, cenexin, in regulating the PCM. Our studies identify that cenexin is required for tempering microtubule nucleation by maintaining PCM cohesion in a PLK1 dependent manner. PCM architecture in cenexin-depleted zebrafish embryos was rescued with wild-type human cenexin, but not with a C-terminal cenexin mutant (S796A) deficient in PLK1 binding. We propose a model where cenexin's C-terminus acts in a conserved manner in eukaryotes, excluding nematodes and arthropods, to sequester PLK1 that limits PCM substrate phosphorylation events required for PCM cohesion. [Media: see text].

DOI: https://doi.org/10.1091/mbc.E22-01-0015
Proc Natl Acad Sci U S A. 2022 May 31. 119(22): e2109838119

Generation of dynamic three-dimensional genome structure through phase separation of chromatin.

Shin Fujishiro, Masaki Sasai.

  Significance DNA functions in living cells are crucially affected by the three-dimensional genome structure and dynamics. We analyze the whole genome of human cells by developing a polymer model of interphase nuclei. The model reveals the essential importance of the unfolding process of chromosomes from the condensed mitotic state for describing the interphase nuclei; through the unfolding process, heterogeneous repulsive interactions among chromatin chains induce phase separation of chromatin, which quantitatively explains the experimentally observed various genomic data. We can use this model structure as a platform to analyze the relationship among genome structure, dynamics, and functions.

Keywords:  A/B compartments; chromatin domains; genome organization; lamina-associated domains; nucleolus-associated domains

DOI:  https://doi.org/10.1073/pnas.2109838119
Pharmaceutics. 2022 Apr 25. pii: 932. [Epub ahead of print]14(5):

SRC Kinase-Mediated Tyrosine Phosphorylation of TUBB3 Regulates Its Stability and Mitotic Spindle Dynamics in Prostate Cancer Cells.

Alan Alfano, Jin Xu, Xi Yang, Dhanraj Deshmukh, Yun Qiu.

  Tubulin is an integral part of the cytoskeleton and plays a pivotal role in cellular signaling, maintenance, and division. β-tubulin is also the molecular target for taxane compounds such as docetaxel (DTX) and cabazitaxel (CTX), both first-line treatments for several solid cancers. Increased expression of Class III β-tubulin (TUBB3), a primarily neural isoform of β-tubulin, correlates with taxane resistance and poor prognosis. Although tyrosine kinase c-Src has been implicated to phosphorylate β-tubulins during both hematopoietic and neural differentiation, the mechanisms by which Src modulates tubulins functions are still poorly understood. Here, we report, for the first time, that TUBB3 is phosphorylated at Tyrosine 340 (Y340) by c-SRC in prostate cancer cells. We also showed that Y340 phosphorylation regulates TUBB3 protein stability and subcellular localization. Furthermore, we demonstrated that inhibition of SRC kinase activity compromises spindle stability in mitotic cells, at least partly due to the lack of TUBB3 Y340 phosphorylation. Given the importance of TUBB3 as a clinical biomarker of poor prognosis and drug resistance, characterization of TUBB3 posttranslational regulation could potentially serve as new biomarkers for disease recurrence and/or treatment failure.

Keywords:  SRC kinase; TUBB3; drug resistance; microtubule; prostate cancer; tubulin; tyrosine phosphorylation

DOI:  https://doi.org/10.3390/pharmaceutics14050932
Chromosome Res. 2022 May 23.

Alternative end-joining originates stable chromosome aberrations induced by etoposide during targeted inhibition of DNA-PKcs in ATM-deficient tumor cells.

Marcelo de Campos Nebel, Micaela Palmitelli, Josefina Pérez Maturo, Marcela González-Cid.

  ATM and DNA-PKcs coordinate the DNA damage response at multiple levels following the exposure to chemotherapy. The Topoisomerase II poison etoposide (ETO) is an effective chemotherapeutic agent that induces DNA double-strand breaks (DSB), but it is responsible from the chromosomal rearrangements frequently found in therapy-related secondary tumors. Targeted inhibition of DNA-PKcs in ATM-defective tumors combined with radio- or chemotherapy has been proposed as relevant therapies. Here, we explored the DNA repair mechanisms and the genetic consequences of targeting the non-oncogenic addiction to DNA-PKcs of ATM-defective tumor cells after exposure to ETO. We demonstrated that chemical inhibition of DNA-PKcs followed by treatment with ETO resulted in the accumulation of chromatid breaks and decreased mitotic index in both A-T cells and ATM-knocked-down (ATMkd) tumor cells. The HR repair process in DNA-PKcs-inhibited ATMkd cells amplified the RAD51 foci number, with no correlated increase in sister chromatid exchanges. The analysis of post-mitotic DNA lesions presented an augmented number of persistent unresolved DSB, without alterations in the cell cycle progression. Long-term examination of chromosome aberrations revealed a strikingly high number of chromatid and chromosome exchanges. By using genetic and pharmacological abrogation of PARP-1, we demonstrated that alternative end-joining (alt-EJ) repair pathway is responsible for those chromosome abnormalities generated by limiting c-NHEJ activities during directed inhibition of DNA-PKcs in ATM-deficient cells. Targeting the non-oncogenic addiction to DNA-PKcs of ATM-defective tumors stimulates the DSB repair by alt-EJ, which is liable for the origin of cells carrying stable chromosome aberrations that may eventually restrict the therapeutic strategy.

Keywords:  ATM-deficient human cells; DNA and chromosome damages; DNA-PKcs inhibition; cell cycle; double-strand break repair; etoposide

DOI:  https://doi.org/10.1007/s10577-022-09700-w
Antioxidants (Basel). 2022 May 11. pii: 946. [Epub ahead of print]11(5):

Transcription Factor NRF2 Participates in Cell Cycle Progression at the Level of G1/S and Mitotic Checkpoints.

Diego Lastra, Maribel Escoll, Antonio Cuadrado.

  Transcription factor NRF2 is a master regulator of the multiple cytoprotective responses that confer growth advantages on a cell. However, its participation in the mechanisms that govern the cell division cycle has not been explored in detail. In this study, we used several standard methods of synchronization of proliferating cells together with flow cytometry and monitored the participation of NRF2 along the cell cycle by the knockdown of its gene expression. We found that the NRF2 levels were highest at S phase entry, and lowest at mitosis. NRF2 depletion promoted both G1 and M arrest. Targeted transcriptomics analysis of cell cycle regulators showed that NRF2 depletion leads to changes in key cell cycle regulators, such as CDK2, TFDP1, CDK6, CDKN1A (p21), CDKN1B (p27), CCNG1, and RAD51. This study gives a new dimension to NRF2 effects, showing their implication in cell cycle progression.

Keywords:  NRF2; cell division cycle; check point; restriction point

DOI:  https://doi.org/10.3390/antiox11050946