1
|
Li S, Kasciukovic T, Tanaka TU. Kinetochore-microtubule error correction for biorientation: lessons from yeast. Biochem Soc Trans 2024; 52:29-39. [PMID: 38305688 PMCID: PMC10903472 DOI: 10.1042/bst20221261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/03/2024]
Abstract
Accurate chromosome segregation in mitosis relies on sister kinetochores forming stable attachments to microtubules (MTs) extending from opposite spindle poles and establishing biorientation. To achieve this, erroneous kinetochore-MT interactions must be resolved through a process called error correction, which dissolves improper kinetochore-MT attachment and allows new interactions until biorientation is achieved. The Aurora B kinase plays key roles in driving error correction by phosphorylating Dam1 and Ndc80 complexes, while Mps1 kinase, Stu2 MT polymerase and phosphatases also regulate this process. Once biorientation is formed, tension is applied to kinetochore-MT interaction, stabilizing it. In this review article, we discuss the mechanisms of kinetochore-MT interaction, error correction and biorientation. We focus mainly on recent insights from budding yeast, where the attachment of a single MT to a single kinetochore during biorientation simplifies the analysis of error correction mechanisms.
Collapse
Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Taciana Kasciukovic
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| | - Tomoyuki U. Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, U.K
| |
Collapse
|
2
|
Li S, Garcia-Rodriguez LJ, Tanaka TU. Chromosome biorientation requires Aurora B's spatial separation from its outer kinetochore substrates, but not its turnover at kinetochores. Curr Biol 2023; 33:4557-4569.e3. [PMID: 37788666 DOI: 10.1016/j.cub.2023.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 08/14/2023] [Accepted: 09/01/2023] [Indexed: 10/05/2023]
Abstract
For correct chromosome segregation in mitosis, sister kinetochores must interact with microtubules from opposite spindle poles (biorientation). For this, aberrant kinetochore-microtubule interaction must be resolved (error correction) by Aurora B kinase. Once biorientation is formed, tension is applied on kinetochore-microtubule interaction, stabilizing this interaction. The mechanism for this tension-dependent process has been debated. Here, we study how Aurora B localizations at different kinetochore sites affect the biorientation establishment and maintenance in budding yeast. Without the physiological Aurora B-INCENP recruitment mechanisms, engineered recruitment of Aurora B-INCENP to the inner kinetochore, but not to the outer kinetochore, prior to biorientation supports the subsequent biorientation establishment. Moreover, when the physiological Aurora B-INCENP recruitment mechanisms are present, an engineered Aurora B-INCENP recruitment to the outer kinetochore, but not to the inner kinetochore, during metaphase (after biorientation establishment) disrupts biorientation, which is dependent on the Aurora B kinase activity. These results suggest that the spatial separation of Aurora B from its outer kinetochore substrates is required to stabilize kinetochore-microtubule interaction when biorientation is formed and tension is applied on this interaction. Meanwhile, Aurora B exhibits dynamic turnover on the centromere/kinetochore during early mitosis, a process thought to be crucial for error correction and biorientation. However, using the engineered Aurora B-INCENP recruitment to the inner kinetochore, we demonstrate that, even without such a turnover, Aurora B-INCENP can efficiently support biorientation. Our study provides important insights into how Aurora B promotes error correction for biorientation in a tension-dependent manner.
Collapse
Affiliation(s)
- Shuyu Li
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Luis J Garcia-Rodriguez
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Tomoyuki U Tanaka
- Division of Molecular, Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
| |
Collapse
|
3
|
Clarke MN, Marsoner T, Adell MAY, Ravichandran MC, Campbell CS. Adaptation to high rates of chromosomal instability and aneuploidy through multiple pathways in budding yeast. EMBO J 2022; 42:e111500. [PMID: 36530167 PMCID: PMC10106982 DOI: 10.15252/embj.2022111500] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 11/08/2022] [Accepted: 11/24/2022] [Indexed: 12/23/2022] Open
Abstract
Both an increased frequency of chromosome missegregation (chromosomal instability, CIN) and the presence of an abnormal complement of chromosomes (aneuploidy) are hallmarks of cancer. To better understand how cells are able to adapt to high levels of chromosomal instability, we previously examined yeast cells that were deleted of the gene BIR1, a member of the chromosomal passenger complex (CPC). We found bir1Δ cells quickly adapted by acquiring specific combinations of beneficial aneuploidies. In this study, we monitored these yeast strains for longer periods of time to determine how cells adapt to high levels of both CIN and aneuploidy in the long term. We identify suppressor mutations that mitigate the chromosome missegregation phenotype. The mutated proteins fall into four main categories: outer kinetochore subunits, the SCFCdc4 ubiquitin ligase complex, the mitotic kinase Mps1, and the CPC itself. The identified suppressor mutations functioned by reducing chromosomal instability rather than alleviating the negative effects of aneuploidy. Following the accumulation of suppressor point mutations, the number of beneficial aneuploidies decreased. These experiments demonstrate a time line of adaptation to high rates of CIN.
Collapse
Affiliation(s)
- Matthew N Clarke
- Department of Chromosome Biology, Max Perutz Labs, Vienna Biocenter (VBC) University of Vienna Vienna Austria
| | - Theodor Marsoner
- Department of Chromosome Biology, Max Perutz Labs, Vienna Biocenter (VBC) University of Vienna Vienna Austria
| | - Manuel Alonso Y Adell
- Department of Chromosome Biology, Max Perutz Labs, Vienna Biocenter (VBC) University of Vienna Vienna Austria
| | - Madhwesh C Ravichandran
- Department of Chromosome Biology, Max Perutz Labs, Vienna Biocenter (VBC) University of Vienna Vienna Austria
| | - Christopher S Campbell
- Department of Chromosome Biology, Max Perutz Labs, Vienna Biocenter (VBC) University of Vienna Vienna Austria
| |
Collapse
|
4
|
Jeong JH, Kim SH, Kim J. CaBir1 functions as an inhibitor-of-apoptosis and affects caspase-like activitiy in Candida albicans. Fungal Genet Biol 2021; 154:103600. [PMID: 34197920 DOI: 10.1016/j.fgb.2021.103600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/14/2021] [Accepted: 06/14/2021] [Indexed: 10/21/2022]
Abstract
CaMca1 is the only metacaspase in Candida albicans, which shows structural homology to the mammalian caspases. CaMca1 consists of the caspase domain, the P20 and P10 regions, and the conserved catalytic histidine-cysteine dyad that is required for executing apoptosis in C. albicans. However, little is known about the proteolytic processing of CaMca1 or its activation under apoptosis-inducing conditions. To understand the regulation of this process, we characterized CaBir1 which is the single IAP (inhibitor-of-apoptosis protein) in C. albicans. IAPs are a family of proteins whose members all harbor a BIR (baculovirus IAP repeat) domain and negatively regulate apoptosis by inhibiting caspases. We found that the Cabir1/Cabir1 deletion mutant exhibited increased apoptotic phenotypes, such as ROS accumulation, nuclear segmentation, and cell survival, under apoptosis-inducing conditions. Examination of CaMca1 cleavage patterns in response to various apoptotic stresses revealed that these cleavages were stress-specific and dependent on the catalytic histidine-cysteine residues of CaMca1. The Cabir1/Cabir1 mutation was not associated with altered CaMca1 processing with or without apoptotic stimuli, but the Cabir1/Cabir1 mutant exhibited significantly increased caspase-like activities. These results suggest that CaBir1 acts as an apoptosis inhibitor by regulating caspase-like activity, but not CaMca1 processing.
Collapse
Affiliation(s)
- Jeong-Hoon Jeong
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Se Hyeon Kim
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jinmi Kim
- Department of Microbiology and Molecular Biology, College of Bioscience and Biotechnology, Chungnam National University, Daejeon 34134, Republic of Korea.
| |
Collapse
|
5
|
Proudfoot KG, Anderson SJ, Dave S, Bunning AR, Sinha Roy P, Bera A, Gupta ML. Checkpoint Proteins Bub1 and Bub3 Delay Anaphase Onset in Response to Low Tension Independent of Microtubule-Kinetochore Detachment. Cell Rep 2020; 27:416-428.e4. [PMID: 30970246 PMCID: PMC6485967 DOI: 10.1016/j.celrep.2019.03.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 05/18/2018] [Accepted: 03/08/2019] [Indexed: 11/23/2022] Open
Abstract
The spindle assembly checkpoint (SAC) delays anaphase onset until sister chromosomes are bound to microtubules from opposite spindle poles. Only then can dynamic microtubules produce tension across sister kinetochores. The interdependence of kinetochore attachment and tension has proved challenging to understanding SAC mechanisms. Whether the SAC responds simply to kinetochore attachment or to tension status remains obscure. Unlike higher eukaryotes, budding yeast kinetochores bind only one microtubule, simplifying the relation between attachment and tension. We developed a Taxol-sensitive yeast model to reduce tension in fully assembled spindles. Our results show that low tension on bipolar-attached kinetochores delays anaphase onset, independent of detachment. The delay is transient relative to that imposed by unattached kinetochores. Furthermore, it is mediated by Bub1 and Bub3, but not Mad1, Mad2, and Mad3 (BubR1). Our results demonstrate that reduced tension delays anaphase onset via a signal that is temporally and mechanistically distinct from that produced by unattached kinetochores. Kinetochore attachment and tension are critical for proper chromosome segregation, but isolating the contribution of either stimulus has been challenging. Using a Taxol-sensitive yeast model, Proudfoot et al. show that reducing tension specifically produces a delay in mitotic progression that is temporally and mechanistically distinct from that produced by unattached kinetochores.
Collapse
Affiliation(s)
- Kathleen G Proudfoot
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA; Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Samuel J Anderson
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Sandeep Dave
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Angela R Bunning
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Pallavi Sinha Roy
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Abesh Bera
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Mohan L Gupta
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA.
| |
Collapse
|
6
|
García-Rodríguez LJ, Kasciukovic T, Denninger V, Tanaka TU. Aurora B-INCENP Localization at Centromeres/Inner Kinetochores Is Required for Chromosome Bi-orientation in Budding Yeast. Curr Biol 2019; 29:1536-1544.e4. [PMID: 31006569 PMCID: PMC6509284 DOI: 10.1016/j.cub.2019.03.051] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/06/2019] [Accepted: 03/22/2019] [Indexed: 12/24/2022]
Abstract
For proper chromosome segregation in mitosis, sister kinetochores must interact with microtubules from opposite spindle poles (chromosome bi-orientation) [1, 2]. To promote bi-orientation, Aurora B kinase disrupts aberrant kinetochore-microtubule interactions [3, 4, 5, 6]. It has long been debated how Aurora B halts this action when bi-orientation is established and tension is applied across sister kinetochores. A popular explanation for it is that, upon bi-orientation, sister kinetochores are pulled in opposite directions, stretching the outer kinetochores [7, 8] and moving Aurora B substrates away from Aurora-B-localizing sites at centromeres (spatial separation model) [3, 5, 9]. This model predicts that Aurora B localization at centromeres is required for bi-orientation. However, this notion was challenged by the observation that Bir1 (yeast survivin), which recruits Ipl1-Sli15 (yeast Aurora B-INCENP) to centromeres, can become dispensable for bi-orientation [10]. This raised the possibility that Aurora B localization at centromeres is dispensable for bi-orientation. Alternatively, there might be a Bir1-independent mechanism for recruiting Ipl1-Sli15 to centromeres or inner kinetochores [5, 9]. Here, we show that the COMA inner kinetochore sub-complex physically interacts with Sli15, recruits Ipl1-Sli15 to the inner kinetochore, and promotes chromosome bi-orientation, independently of Bir1, in budding yeast. Moreover, using an engineered recruitment of Ipl1-Sli15 to the inner kinetochore when both Bir1 and COMA are defective, we show that localization of Ipl1-Sli15 at centromeres or inner kinetochores is required for bi-orientation. Our results give important insight into how Aurora B disrupts kinetochore-microtubule interaction in a tension-dependent manner to promote chromosome bi-orientation. The COMA inner kinetochore sub-complex facilitates chromosome bi-orientation COMA physically interacts with Sli15 and recruits Ipl1-Sli15 to the inner kinetochore This function of COMA is independent of Bir1 and its role supporting robust cohesion Localizing Ipl1-Sli15 at centromeres/inner kinetochores is crucial for bi-orientation
Collapse
Affiliation(s)
- Luis J García-Rodríguez
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Taciana Kasciukovic
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Viola Denninger
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
| |
Collapse
|
7
|
Fong KK, Zelter A, Graczyk B, Hoyt JM, Riffle M, Johnson R, MacCoss MJ, Davis TN. Novel phosphorylation states of the yeast spindle pole body. Biol Open 2018; 7:bio.033647. [PMID: 29903865 PMCID: PMC6215409 DOI: 10.1242/bio.033647] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Phosphorylation regulates yeast spindle pole body (SPB) duplication and separation and likely regulates microtubule nucleation. We report a phosphoproteomic analysis using tandem mass spectrometry of enriched Saccharomyces cerevisiae SPBs for two cell cycle arrests, G1/S and the mitotic checkpoint, expanding on previously reported phosphoproteomic data sets. We present a novel phosphoproteomic state of SPBs arrested in G1/S by a cdc4-1 temperature-sensitive mutation, with particular focus on phosphorylation events on the γ-tubulin small complex (γ-TuSC). The cdc4-1 arrest is the earliest arrest at which microtubule nucleation has occurred at the newly duplicated SPB. Several novel phosphorylation sites were identified in G1/S and during mitosis on the microtubule nucleating γ-TuSC. These sites were analyzed in vivo by fluorescence microscopy and were shown to be required for proper regulation of spindle length. Additionally, in vivo analysis of two mitotic sites in Spc97 found that phosphorylation of at least one of these sites is required for progression through the cell cycle. This phosphoproteomic data set not only broadens the scope of the phosphoproteome of SPBs, it also identifies several γ-TuSC phosphorylation sites that influence microtubule formation. Summary: A phosphoproteome of yeast spindle pole bodies in G1/S or M phase identifies phosphorylation sites involved in spindle length control and provides direction for future phosphorylation analyses of spindle pole components.
Collapse
Affiliation(s)
- Kimberly K Fong
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Alex Zelter
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Beth Graczyk
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Jill M Hoyt
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Michael Riffle
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Richard Johnson
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
8
|
Makrantoni V, Ciesiolka A, Lawless C, Fernius J, Marston A, Lydall D, Stark MJR. A Functional Link Between Bir1 and the Saccharomyces cerevisiae Ctf19 Kinetochore Complex Revealed Through Quantitative Fitness Analysis. G3 (BETHESDA, MD.) 2017; 7:3203-3215. [PMID: 28754723 PMCID: PMC5592945 DOI: 10.1534/g3.117.300089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/25/2017] [Indexed: 11/18/2022]
Abstract
The chromosomal passenger complex (CPC) is a key regulator of eukaryotic cell division, consisting of the protein kinase Aurora B/Ipl1 in association with its activator (INCENP/Sli15) and two additional proteins (Survivin/Bir1 and Borealin/Nbl1). Here, we report a genome-wide genetic interaction screen in Saccharomyces cerevisiae using the bir1-17 mutant, identifying through quantitative fitness analysis deletion mutations that act as enhancers and suppressors. Gene knockouts affecting the Ctf19 kinetochore complex were identified as the strongest enhancers of bir1-17, while mutations affecting the large ribosomal subunit or the mRNA nonsense-mediated decay pathway caused strong phenotypic suppression. Thus, cells lacking a functional Ctf19 complex become highly dependent on Bir1 function and vice versa. The negative genetic interaction profiles of bir1-17 and the cohesin mutant mcd1-1 showed considerable overlap, underlining the strong functional connection between sister chromatid cohesion and chromosome biorientation. Loss of some Ctf19 components, such as Iml3 or Chl4, impacted differentially on bir1-17 compared with mutations affecting other CPC components: despite the synthetic lethality shown by either iml3∆ or chl4∆ in combination with bir1-17, neither gene knockout showed any genetic interaction with either ipl1-321 or sli15-3 Our data therefore imply a specific functional connection between the Ctf19 complex and Bir1 that is not shared with Ipl1.
Collapse
Affiliation(s)
- Vasso Makrantoni
- Centre for Gene Regulation and Expression, University of Dundee, DD1 5EH, UK
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - Adam Ciesiolka
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Conor Lawless
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Josefin Fernius
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - Adele Marston
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - David Lydall
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Michael J R Stark
- Centre for Gene Regulation and Expression, University of Dundee, DD1 5EH, UK
| |
Collapse
|
9
|
Edgerton H, Johansson M, Keifenheim D, Mukherjee S, Chacón JM, Bachant J, Gardner MK, Clarke DJ. A noncatalytic function of the topoisomerase II CTD in Aurora B recruitment to inner centromeres during mitosis. J Cell Biol 2017; 213:651-64. [PMID: 27325791 PMCID: PMC4915189 DOI: 10.1083/jcb.201511080] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/25/2016] [Indexed: 11/22/2022] Open
Abstract
The C-terminal domain (CTD) of Topo II is dispensable for its catalytic activity yet essential for Topo II function in chromosome segregation during mitosis. Here, Edgerton et al. resolve the role of the Topo II CTD during mitosis in yeast, showing that it functions noncatalytically via the Haspin-H3 T3-Phos pathway to recruit Ipl1/Aurora B to mitotic inner centromeres. Faithful chromosome segregation depends on the precise timing of chromatid separation, which is enforced by checkpoint signals generated at kinetochores. Here, we provide evidence that the C-terminal domain (CTD) of DNA topoisomerase IIα (Topo II) provides a novel function at inner centromeres of kinetochores in mitosis. We find that the yeast CTD is required for recruitment of the tension checkpoint kinase Ipl1/Aurora B to inner centromeres in metaphase but is not required in interphase. Conserved CTD SUMOylation sites are required for Ipl1 recruitment. This inner-centromere CTD function is distinct from the catalytic activity of Topo II. Genetic and biochemical evidence suggests that Topo II recruits Ipl1 via the Haspin–histone H3 threonine 3 phosphorylation pathway. Finally, Topo II and Sgo1 are equally important for Ipl1 recruitment to inner centromeres. This indicates H3 T3-Phos/H2A T120-Phos is a universal epigenetic signature that defines the eukaryotic inner centromere and provides the binding site for Ipl1/Aurora B.
Collapse
Affiliation(s)
- Heather Edgerton
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Marnie Johansson
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Daniel Keifenheim
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Soumya Mukherjee
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Jeremy M Chacón
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Jeff Bachant
- Department of Cell Biology and Neuroscience, University of California, Riverside, Riverside, CA 92521
| | - Melissa K Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Duncan J Clarke
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
10
|
Thu YM, Van Riper SK, Higgins L, Zhang T, Becker JR, Markowski TW, Nguyen HD, Griffin TJ, Bielinsky AK. Slx5/Slx8 Promotes Replication Stress Tolerance by Facilitating Mitotic Progression. Cell Rep 2016; 15:1254-65. [PMID: 27134171 DOI: 10.1016/j.celrep.2016.04.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 01/30/2016] [Accepted: 03/31/2016] [Indexed: 11/30/2022] Open
Abstract
Loss of minichromosome maintenance protein 10 (Mcm10) causes replication stress. We uncovered that S. cerevisiae mcm10-1 mutants rely on the E3 SUMO ligase Mms21 and the SUMO-targeted ubiquitin ligase complex Slx5/8 for survival. Using quantitative mass spectrometry, we identified changes in the SUMO proteome of mcm10-1 mutants and revealed candidates regulated by Slx5/8. Such candidates included subunits of the chromosome passenger complex (CPC), Bir1 and Sli15, known to facilitate spindle assembly checkpoint (SAC) activation. We show here that Slx5 counteracts SAC activation in mcm10-1 mutants under conditions of moderate replication stress. This coincides with the proteasomal degradation of sumoylated Bir1. Importantly, Slx5-dependent mitotic relief was triggered not only by Mcm10 deficiency but also by treatment with low doses of the alkylating drug methyl methanesulfonate. Based on these findings, we propose a model in which Slx5/8 allows for passage through mitosis when replication stress is tolerable.
Collapse
Affiliation(s)
- Yee Mon Thu
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Susan Kaye Van Riper
- University of Minnesota Informatics Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tianji Zhang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jordan Robert Becker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Todd William Markowski
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hai Dang Nguyen
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Timothy Jon Griffin
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Anja Katrin Bielinsky
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
11
|
Ring closure activates yeast γTuRC for species-specific microtubule nucleation. Nat Struct Mol Biol 2015; 22:132-7. [PMID: 25599398 PMCID: PMC4318760 DOI: 10.1038/nsmb.2953] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 12/12/2014] [Indexed: 12/23/2022]
Abstract
The γ-tubulin ring complex (γTuRC) is the primary microtubule nucleator in cells. γTuRC is assembled from repeating γ-tubulin small complex (γTuSC) subunits and is thought to function as a template by presenting a γ-tubulin ring that mimics microtubule geometry. However, a previous yeast γTuRC structure showed γTuSC in an open conformation that prevents matching to microtubule symmetry. By contrast, we show here that γ-tubulin complexes are in a closed conformation when attached to microtubules. To confirm the functional importance of the closed γTuSC ring, we trapped the closed state and determined its structure, showing that the γ-tubulin ring precisely matches microtubule symmetry and providing detailed insight into γTuRC architecture. Importantly, the closed state is a stronger nucleator, thus suggesting that this conformational switch may allosterically control γTuRC activity. Finally, we demonstrate that γTuRCs have a strong preference for tubulin from the same species.
Collapse
|
12
|
Saleh AA, Bhadra AK, Roy I. Cytotoxicity of mutant huntingtin fragment in yeast can be modulated by the expression level of wild type huntingtin fragment. ACS Chem Neurosci 2014; 5:205-15. [PMID: 24377263 PMCID: PMC3963126 DOI: 10.1021/cn400171d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 12/26/2013] [Indexed: 12/23/2022] Open
Abstract
Conflicting reports exist in the literature regarding the role of wild-type huntingtin in determining the toxicity of the aggregated, mutant huntingtin in Huntington's disease (HD). Some studies report the amelioration of toxicity of the mutant protein in the presence of the wild-type protein, while others indicate sequestration of the wild-type protein by mutant huntingtin. Over the years, yeast has been established as a valid model organism to study molecular changes associated with HD, especially at the protein level. We have used an inducible system to express human huntingtin fragments harboring normal (25Q) and pathogenic (103Q) polyglutamine lengths under the control of a galactose promoter in a yeast model of HD. We show that the relative expression level of each allele (wild-type/mutant) decides the cellular phenotype. When the expression level of wild-type huntingtin is high, an increase in the solubility of the mutant protein is observed. Fluorescence-recovery-after-photobleaching (FRAP) studies show that solubility reaches ∼94% in these cells. This leads to reduction in oxidative stress and cytotoxicity, and increases cell viability. In-cell FRET studies show that interaction between these proteins does not require the presence of a mediator. When the expression of wild-type huntingtin is low, it is sequestered into aggregates by the mutant protein. Even under these conditions, cytotoxicity is attenuated. Our findings indicate that the presence of wild-type huntingtin has a beneficial role even when its relative expression level is lower than that of the mutant protein.
Collapse
Affiliation(s)
- Aliabbas Ahmedbhai Saleh
- Department of Biotechnology, National Institute
of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab 160 062, India
| | - Ankan Kumar Bhadra
- Department of Biotechnology, National Institute
of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab 160 062, India
| | - Ipsita Roy
- Department of Biotechnology, National Institute
of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab 160 062, India
| |
Collapse
|
13
|
Phosphorylation of Sli15 by Ipl1 is important for proper CPC localization and chromosome stability in Saccharomyces cerevisiae. PLoS One 2014; 9:e89399. [PMID: 24558497 PMCID: PMC3928436 DOI: 10.1371/journal.pone.0089399] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/19/2014] [Indexed: 12/29/2022] Open
Abstract
The chromosomal passenger complex (CPC) is a key regulator of eukaryotic cell division, consisting of the protein kinase Aurora B/Ipl1 in association with its activator (INCENP/Sli15) and two additional proteins (Survivin/Bir1 and Borealin/Nbl1). Here we have identified multiple sites of CPC autophosphorylation on yeast Sli15 that are located within its central microtubule-binding domain and examined the functional significance of their phosphorylation by Ipl1 through mutation of these sites, either to non-phosphorylatable alanine (sli15-20A) or to acidic residues to mimic constitutive phosphorylation (sli15-20D). Both mutant sli15 alleles confer chromosome instability, but this is mediated neither by changes in the capacity of Sli15 to activate Ipl1 kinase nor by decreased efficiency of chromosome biorientation, a key process in cell division that requires CPC function. Instead, we find that mimicking constitutive phosphorylation of Sli15 on the Ipl1 phosphorylation sites causes delocalization of the CPC in metaphase, whereas blocking phosphorylation of Sli15 on the Ipl1 sites drives excessive localization of Sli15 to the mitotic spindle in pre-anaphase cells. Consistent with these results, direct interaction of Sli15 with microtubules in vitro is greatly reduced either following phosphorylation by Ipl1 or when constitutive phosphorylation at the Ipl1-dependent phosphorylation sites is mimicked by aspartate or glutamate substitutions. Furthermore, we find that mimicking Ipl1 phosphorylation of Sli15 interferes with the ‘tension checkpoint’ – the CPC-dependent mechanism through which cells activate the spindle assembly checkpoint to delay anaphase in the absence of tension on kinetochore-microtubule attachments. Ipl1-dependent phosphorylation of Sli15 therefore inhibits its association with microtubules both in vivo and in vitro and may negatively regulate the tension checkpoint mechanism.
Collapse
|
14
|
Tanaka TU, Clayton L, Natsume T. Three wise centromere functions: see no error, hear no break, speak no delay. EMBO Rep 2013; 14:1073-83. [PMID: 24232185 PMCID: PMC3849490 DOI: 10.1038/embor.2013.181] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 10/18/2013] [Indexed: 12/17/2022] Open
Abstract
The main function of the centromere is to promote kinetochore assembly for spindle microtubule attachment. Two additional functions of the centromere, however, are becoming increasingly clear: facilitation of robust sister-chromatid cohesion at pericentromeres and advancement of replication of centromeric regions. The combination of these three centromere functions ensures correct chromosome segregation during mitosis. Here, we review the mechanisms of the kinetochore-microtubule interaction, focusing on sister-kinetochore bi-orientation (or chromosome bi-orientation). We also discuss the biological importance of robust pericentromeric cohesion and early centromere replication, as well as the mechanisms orchestrating these two functions at the microtubule attachment site.
Collapse
Affiliation(s)
- Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | | | | |
Collapse
|
15
|
Tension sensing by Aurora B kinase is independent of survivin-based centromere localization. Nature 2013; 497:118-21. [PMID: 23604256 PMCID: PMC3644022 DOI: 10.1038/nature12057] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/05/2013] [Indexed: 12/18/2022]
Abstract
Accurate segregation of the replicated genome requires chromosome biorientation on the spindle. Biorientation is ensured by Aurora B kinase, a member of the 4-subunit chromosomal passenger complex (CPC)1,2. Localization of the CPC to the inner centromere is central to the current model for how tension ensures chromosome biorientation—kinetochore-spindle attachments not under tension remain close to the inner centromere and are destabilized by Aurora B phosphorylation, whereas kinetochores under tension are pulled away from the influence of Aurora B, stabilizing their microtubule attachments3–5. Here we show that an engineered truncation of the INCENP/Sli15 subunit of budding yeast CPC that eliminates association with the inner centromere nevertheless supports proper chromosome segregation during both mitosis and meiosis. Truncated INCENP/Sli15 suppresses the deletion phenotypes of the inner centromere-targeting proteins Survivin/Bir1, Borealin/Nbl1, Bub1 and Sgo16. Unlike wildtype INCENP/Sli15, truncated INCENP/Sli15 localizes to pre-anaphase spindle microtubules. Premature targeting of full-length INCENP/Sli15 to microtubules by preventing Cdk1 phosphorylation also suppresses inviability of Survivin/Bir1 deletion. These results suggest that activation of Aurora B/Ipl1 by clustering either on chromatin or on microtubules is sufficient for chromosome biorientation.
Collapse
|
16
|
Abstract
Nuclear pore complexes (NPCs) and kinetochores perform distinct tasks, yet their shared ability to bind several proteins suggests their functions are intertwined. Among these shared proteins is Mad1p, a component of the yeast spindle assembly checkpoint (SAC). Here we describe a role for Mad1p in regulating nuclear import that employs its ability to sense a disruption of kinetochore-microtubule interactions during mitosis. We show that kinetochore-microtubule detachment arrests nuclear import mediated by the transport factor Kap121p through a mechanism that requires Mad1p cycling between unattached, metaphase kinetochores and binding sites at the NPC. This signaling pathway requires the Aurora B-like kinase Ipl1p, and the resulting transport changes inhibit the nuclear import of Glc7p, a phosphatase that acts as an Ipl1p antagonist. We propose that a distinct branch of the SAC exists in which Mad1p senses unattached kinetochores and, by altering NPC transport activity, regulates the nuclear environment of the spindle.
Collapse
|
17
|
Gao K, Xiong Q, Xu J, Wang K, Wang K. CpBir1 is required for conidiation, virulence and anti-apoptotic effects and influences hypovirus transmission in Cryphonectria parasitica. Fungal Genet Biol 2012; 51:60-71. [PMID: 23084963 DOI: 10.1016/j.fgb.2012.09.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 12/29/2022]
Abstract
Inhibitors of apoptosis proteins (IAPs) are critically important in the regulation of unicellular yeast and metazoan apoptosis. All IAPs contain one to three baculovirus IAP repeat (BIR) domains, which are essential for the anti-apoptotic activity of the IAPs. A homolog of IAPs, CpBir1, which bears two BIR domains, was recently identified from the chestnut blight fungus Cryphonectria parasitica genome. CpIAP was deleted by gene replacement, and the phenotypes of ΔIAP were characterized. CpBir1 was significantly down-regulated by hypovirus infection but up-regulated by H(2)O(2). Similar to Saccharomyces cerevisiae Bir1p, the Cpbir1 mutant was sensitive to H(2)O(2), and constitutive overexpression of CpBir1 increased resistance to H(2)O(2). The Cpbir1 mutant also showed defects in aerial hyphal formation, colony growth, mycelial morphology, conidiogenesis, pigmentation, resistance to stress conditions and virulence. Genetic complementation with native Cpbir1 fully recovered all these defective phenotypes. The CpBir1-eGFP fusion protein was localized to the nucleus in juvenile cultures, while it was found in the cytoplasm in old cultures, suggesting that the localization pattern of CpBir1 may correlate with the process of anti-apoptosis. Increased accumulation of reactive oxygen species (ROS) in the Cpbir1 deletion mutant further supports the anti-apoptotic function of CpBir1. Among five selected vegetative compatible (vc) types of C. parasitica, Cpbir1 deletion was found to block virus from transferring between Cpbir1 mutants. However, hypovirus infected Cpbir1 mutants showed a similar ability to transmit virus to other virus-free isolates compared with the infected wild-type strain. In summary, Cpbir1 encodes an IAP CpBir1 that is down-regulated by hypovirus infection and required for conidiation, virulence and anti-apoptosis, as well as affects hypovirus transmission in chestnut blight fungus C. parasitica.
Collapse
Affiliation(s)
- Kun Gao
- Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing 210095, China
| | | | | | | | | |
Collapse
|
18
|
Coffman VC, Wu JQ. Counting protein molecules using quantitative fluorescence microscopy. Trends Biochem Sci 2012; 37:499-506. [PMID: 22948030 DOI: 10.1016/j.tibs.2012.08.002] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 08/01/2012] [Accepted: 08/07/2012] [Indexed: 11/24/2022]
Abstract
In recent years, quantification of absolute protein numbers in cellular structures using fluorescence microscopy has become a reality. Two popular methods are available to a broad range of researchers with minimal equipment and analysis requirements: stepwise photobleaching to count discrete changes in intensity from a small number of fluorescent fusion proteins, and comparing the fluorescence intensity of a protein to a known in vivo or in vitro standard. This review summarizes the advantages and disadvantages of each method, and gives recent examples of each that answer important questions in their respective fields. We also highlight new counting methods that could become widely available in the future.
Collapse
Affiliation(s)
- Valerie C Coffman
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA
| | | |
Collapse
|
19
|
Umbreit NT, Davis TN. Mitosis puts sisters in a strained relationship: force generation at the kinetochore. Exp Cell Res 2012; 318:1361-6. [PMID: 22564894 DOI: 10.1016/j.yexcr.2012.04.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 04/21/2012] [Accepted: 04/23/2012] [Indexed: 11/24/2022]
Abstract
During mitosis, kinetochores couple chromosomes to the dynamic tips of spindle microtubules. These attachments convert chemical energy stored in the microtubule lattice into mechanical energy, generating force to move chromosomes. In addition to mediating robust microtubule attachments, kinetochores also integrate and respond to regulatory signals that ensure the accuracy of chromosome segregation during each cell division. Signals for corrective detachment act specifically on kinetochore-microtubule attachments that fail to generate normal levels of tension, although it is unclear how tension is sensed and how the attachments are released. In this review, we discuss the mechanisms by which kinetochore-microtubule attachments generate force during chromosome biorientation, and the pathways of maturation and regulation that lead to the formation of correct attachments.
Collapse
Affiliation(s)
- Neil T Umbreit
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | | |
Collapse
|
20
|
Coffman VC, Wu P, Parthun MR, Wu JQ. CENP-A exceeds microtubule attachment sites in centromere clusters of both budding and fission yeast. ACTA ACUST UNITED AC 2012; 195:563-72. [PMID: 22084306 PMCID: PMC3257534 DOI: 10.1083/jcb.201106078] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The stoichiometries of kinetochores and their constituent proteins in yeast and vertebrate cells were determined using the histone H3 variant CENP-A, known as Cse4 in budding yeast, as a counting standard. One Cse4-containing nucleosome exists in the centromere (CEN) of each chromosome, so it has been assumed that each anaphase CEN/kinetochore cluster contains 32 Cse4 molecules. We report that anaphase CEN clusters instead contained approximately fourfold more Cse4 in Saccharomyces cerevisiae and ~40-fold more CENP-A (Cnp1) in Schizosaccharomyces pombe than predicted. These results suggest that the number of CENP-A molecules exceeds the number of kinetochore-microtubule (MT) attachment sites on each chromosome and that CENP-A is not the sole determinant of kinetochore assembly sites in either yeast. In addition, we show that fission yeast has enough Dam1-DASH complex for ring formation around attached MTs. The results of this study suggest the need for significant revision of existing CEN/kinetochore architectural models.
Collapse
Affiliation(s)
- Valerie C Coffman
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA
| | | | | | | |
Collapse
|
21
|
Srikantan S, Abdelmohsen K, Lee EK, Tominaga K, Subaran SS, Kuwano Y, Kulshrestha R, Panchakshari R, Kim HH, Yang X, Martindale JL, Marasa BS, Kim MM, Wersto RP, Indig FE, Chowdhury D, Gorospe M. Translational control of TOP2A influences doxorubicin efficacy. Mol Cell Biol 2011; 31:3790-801. [PMID: 21768308 PMCID: PMC3165726 DOI: 10.1128/mcb.05639-11] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 07/05/2011] [Indexed: 12/15/2022] Open
Abstract
The cellular abundance of topoisomerase IIα (TOP2A) critically maintains DNA topology after replication and determines the efficacy of TOP2 inhibitors in chemotherapy. Here, we report that the RNA-binding protein HuR, commonly overexpressed in cancers, binds to the TOP2A 3'-untranslated region (3'UTR) and increases TOP2A translation. Reducing HuR levels triggered the recruitment of TOP2A transcripts to RNA-induced silencing complex (RISC) components and to cytoplasmic processing bodies. Using a novel MS2-tagged RNA precipitation method, we identified microRNA miR-548c-3p as a mediator of these effects and further uncovered that the interaction of miR-548c-3p with the TOP2A 3'UTR repressed TOP2A translation by antagonizing the action of HuR. Lowering TOP2A by silencing HuR or by overexpressing miR-548c-3p selectively decreased DNA damage after treatment with the chemotherapeutic agent doxorubicin. In sum, HuR enhances TOP2A translation by competing with miR-548c-3p; their combined actions control TOP2A expression levels and determine the effectiveness of doxorubicin.
Collapse
MESH Headings
- 3' Untranslated Regions
- Antibiotics, Antineoplastic/pharmacology
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Antigens, Surface/genetics
- Antigens, Surface/metabolism
- DNA/metabolism
- DNA Damage/drug effects
- DNA Topoisomerases, Type II/biosynthesis
- DNA Topoisomerases, Type II/genetics
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/genetics
- Doxorubicin/pharmacology
- ELAV Proteins
- ELAV-Like Protein 1
- Gene Expression Regulation
- HeLa Cells
- Humans
- MicroRNAs/genetics
- MicroRNAs/metabolism
- Poly-ADP-Ribose Binding Proteins
- Protein Biosynthesis
- RNA Interference
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering
- RNA-Binding Proteins/antagonists & inhibitors
- RNA-Binding Proteins/biosynthesis
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- RNA-Induced Silencing Complex/metabolism
Collapse
Affiliation(s)
- Subramanya Srikantan
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Kotb Abdelmohsen
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Eun Kyung Lee
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Kumiko Tominaga
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Sarah S. Subaran
- Research Resources Branch, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Yuki Kuwano
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Ritu Kulshrestha
- Dana-Farber Cancer Institute, Department of Radiation Oncology, Harvard Medical School, Boston, Massachusetts 02118
| | - Rohit Panchakshari
- Dana-Farber Cancer Institute, Department of Radiation Oncology, Harvard Medical School, Boston, Massachusetts 02118
| | - Hyeon Ho Kim
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
- Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Xiaoling Yang
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | | | - Bernard S. Marasa
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Mihee M. Kim
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Robert P. Wersto
- Research Resources Branch, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Fred E. Indig
- Research Resources Branch, NIA-IRP, NIH, Baltimore, Maryland 21224
| | - Dipanjan Chowdhury
- Dana-Farber Cancer Institute, Department of Radiation Oncology, Harvard Medical School, Boston, Massachusetts 02118
| | - Myriam Gorospe
- Laboratory of Molecular Biology and Immunology, NIA-IRP, NIH, Baltimore, Maryland 21224
| |
Collapse
|
22
|
Nakajima Y, Cormier A, Tyers RG, Pigula A, Peng Y, Drubin DG, Barnes G. Ipl1/Aurora-dependent phosphorylation of Sli15/INCENP regulates CPC-spindle interaction to ensure proper microtubule dynamics. ACTA ACUST UNITED AC 2011; 194:137-53. [PMID: 21727193 PMCID: PMC3135399 DOI: 10.1083/jcb.201009137] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Dynamic microtubules facilitate chromosome arrangement before anaphase, whereas during anaphase microtubule stability assists chromosome separation. Changes in microtubule dynamics at the metaphase-anaphase transition are regulated by Cdk1. Cdk1-mediated phosphorylation of Sli15/INCENP promotes preanaphase microtubule dynamics by preventing chromosomal passenger complex (CPC; Sli15/INCENP, Bir1/Survivin, Nbl1/Borealin, Ipl1/Aurora) association with spindles. However, whether Cdk1 has sole control over microtubule dynamics, and how CPC-microtubule association influences microtubule behavior, are unclear. Here, we show that Ipl1/Aurora-dependent phosphorylation of Sli15/INCENP modulates microtubule dynamics by preventing CPC binding to the preanaphase spindle and to the central spindle until late anaphase, facilitating spatiotemporal control of microtubule dynamics required for proper metaphase centromere positioning and anaphase spindle elongation. Decreased Ipl1-dependent Sli15 phosphorylation drives direct CPC binding to microtubules, revealing how the CPC influences microtubule dynamics. We propose that Cdk1 and Ipl1/Aurora cooperatively modulate microtubule dynamics and that Ipl1/Aurora-dependent phosphorylation of Sli15 controls spindle function by excluding the CPC from spindle regions engaged in microtubule polymerization.
Collapse
Affiliation(s)
- Yuko Nakajima
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | | | | | | | | | | | | |
Collapse
|
23
|
Wargacki MM, Tay JC, Muller EG, Asbury CL, Davis TN. Kip3, the yeast kinesin-8, is required for clustering of kinetochores at metaphase. Cell Cycle 2011; 9:2581-8. [PMID: 20603597 DOI: 10.4161/cc.9.13.12076] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In Saccharomyces cerevisiae, chromosome congression clusters kinetochores on either side of the spindle equator at metaphase. Many organisms require one or more kinesin-8 molecular motors to achieve chromosome alignment. The yeast kinesin-8, Kip3, has been well studied in vitro but a role in chromosome congression has not been reported. We investigated Kip3's role in this process using semi-automated, quantitative fluorescence microscopy and time-lapse imaging and found that Kip3 is required for congression. Deletion of KIP3 increases inter-kinetochore distances and increases the variability in the position of sister kinetochores along the spindle axis during metaphase. Kip3 does not regulate spindle length and is not required for kinetochore-microtubule attachment. Instead, Kip3 clusters kinetochores on the metaphase spindle by tightly regulating kinetochore microtubule lengths.
Collapse
Affiliation(s)
- Megan M Wargacki
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | | | | | | | | |
Collapse
|
24
|
Storchová Z, Becker JS, Talarek N, Kögelsberger S, Pellman D. Bub1, Sgo1, and Mps1 mediate a distinct pathway for chromosome biorientation in budding yeast. Mol Biol Cell 2011; 22:1473-85. [PMID: 21389114 PMCID: PMC3084670 DOI: 10.1091/mbc.e10-08-0673] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The conserved mitotic kinase Bub1 performs multiple functions that are only partially characterized. Besides its role in the spindle assembly checkpoint and chromosome alignment, Bub1 is crucial for the kinetochore recruitment of multiple proteins, among them Sgo1. Both Bub1 and Sgo1 are dispensable for growth of haploid and diploid budding yeast, but they become essential in cells with higher ploidy. We find that overexpression of SGO1 partially corrects the chromosome segregation defect of bub1Δ haploid cells and restores viability to bub1Δ tetraploid cells. Using an unbiased high-copy suppressor screen, we identified two members of the chromosomal passenger complex (CPC), BIR1 (survivin) and SLI15 (INCENP, inner centromere protein), as suppressors of the growth defect of both bub1Δ and sgo1Δ tetraploids, suggesting that these mutants die due to defects in chromosome biorientation. Overexpression of BIR1 or SLI15 also complements the benomyl sensitivity of haploid bub1Δ and sgo1Δ cells. Mutants lacking SGO1 fail to biorient sister chromatids attached to the same spindle pole (syntelic attachment) after nocodazole treatment. Moreover, the sgo1Δ cells accumulate syntelic attachments in unperturbed mitoses, a defect that is partially corrected by BIR1 or SLI15 overexpression. We show that in budding yeast neither Bub1 nor Sgo1 is required for CPC localization or affects Aurora B activity. Instead we identify Sgo1 as a possible partner of Mps1, a mitotic kinase suggested to have an Aurora B-independent function in establishment of biorientation. We found that Sgo1 overexpression rescues defects caused by metaphase inactivation of Mps1 and that Mps1 is required for Sgo1 localization to the kinetochore. We propose that Bub1, Sgo1, and Mps1 facilitate chromosome biorientation independently of the Aurora B-mediated pathway at the budding yeast kinetochore and that both pathways are required for the efficient turnover of syntelic attachments.
Collapse
Affiliation(s)
- Zuzana Storchová
- Department of Pediatric Oncology, Children's Hospital, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | | | | | | | | |
Collapse
|
25
|
Shimogawa MM, Wargacki MM, Muller EG, Davis TN. Laterally attached kinetochores recruit the checkpoint protein Bub1, but satisfy the spindle checkpoint. Cell Cycle 2011; 9:3619-28. [PMID: 20928940 DOI: 10.4161/cc.9.17.12907] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Kinetochore attachment to the ends of dynamic microtubules is a conserved feature of mitotic spindle organization that is thought to be critical for proper chromosome segregation. Although kinetochores have been described to transition from lateral to end-on attachments, the phase of lateral attachment has been difficult to study in yeast due to its transient nature. We have previously described a kinetochore mutant, DAM1-765, which exhibits lateral attachments and misregulation of microtubule length. Here we show that the misregulation of microtubule length in DAM1-765 cells occurs despite localization of microtubule associated proteins Bik1, Stu2, Cin8, and Kip3 to microtubules. DAM1-765 kinetochores recruit the spindle checkpoint protein Bub1, however Bub1 localization to DAM1-765 kinetochores is not sufficient to cause a cell cycle arrest. Interestingly, the DAM1-765 mutation rescues the temperature sensitivity of a biorientation-deficient ipl1-321 mutant, and DAM1-765 chromosome loss rates are similar to wild-type cells. The spindle checkpoint in DAM1-765 cells responds properly to unattached kinetochores created by nocodazole treatment and loss of tension caused by a cohesin mutant. Progression of DAM1-765 cells through mitosis therefore suggests that satisfaction of the checkpoint depends more highly on biorientation of sister kinetochores than on achievement of a specific interaction between kinetochores and microtubule plus ends.
Collapse
|
26
|
Kinetochore-microtubule interactions: steps towards bi-orientation. EMBO J 2010; 29:4070-82. [PMID: 21102558 DOI: 10.1038/emboj.2010.294] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 10/29/2010] [Indexed: 11/08/2022] Open
Abstract
Eukaryotic cells segregate their chromosomes accurately to opposite poles during mitosis, which is necessary for maintenance of their genetic integrity. This process mainly relies on the forces generated by kinetochore-microtubule (KT-MT) attachment. During prometaphase, the KT initially interacts with a single MT extending from a spindle pole and then moves towards a spindle pole. Subsequently, MTs from the other spindle pole also interact with the KT. Eventually, one sister KT becomes attached to MTs from one pole while the other sister to those from the other pole (sister KT bi-orientation). If sister KTs interact with MTs with aberrant orientation, this must be corrected to attain proper bi-orientation (error correction) before the anaphase is initiated. Here, I discuss how KTs initially interact with MTs and how this interaction develops into bi-orientation; both processes are fundamentally crucial for proper chromosome segregation in the subsequent anaphase.
Collapse
|
27
|
Leber B, Maier B, Fuchs F, Chi J, Riffel P, Anderhub S, Wagner L, Ho AD, Salisbury JL, Boutros M, Krämer A. Proteins required for centrosome clustering in cancer cells. Sci Transl Med 2010; 2:33ra38. [PMID: 20505215 DOI: 10.1126/scitranslmed.3000915] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Current cancer chemotherapies are limited by the lack of tumor-specific targets, which would allow for selective eradication of malignant cells without affecting healthy tissues. In contrast to normal cells, most tumor cells contain multiple centrosomes, which tend to cause the formation of multipolar mitotic spindles, chromosome segregation defects, and cell death. Nevertheless, many cancer cells divide successfully because they can cluster multiple centrosomes into two spindle poles. Inhibition of this centrosomal clustering, with consequent induction of multipolar spindles and subsequent cell death, would specifically target cancer cells and overcome one limitation of current cancer treatments. We have performed a genome-wide RNA interference screen to identify proteins involved in the prevention of spindle multipolarity in human cancer cells with supernumerary centrosomes. The chromosomal passenger complex, Ndc80 microtubule-kinetochore attachment complex, sister chromatid cohesion, and microtubule formation via the augmin complex were identified as necessary for centrosomal clustering. We show that spindle tension is required to cluster multiple centrosomes into a bipolar spindle array in tumor cells with extra centrosomes. These findings may explain the specificity of drugs that interfere with spindle tension for cancer cells and provide entry points for the development of therapeutics.
Collapse
Affiliation(s)
- Blanka Leber
- Clinical Cooperation Unit Molecular Hematology/Oncology, German Cancer Research Center and Department of Internal Medicine V, University of Heidelberg, 69120 Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Keating P, Rachidi N, Tanaka TU, Stark MJR. Ipl1-dependent phosphorylation of Dam1 is reduced by tension applied on kinetochores. J Cell Sci 2010; 122:4375-82. [PMID: 19923271 DOI: 10.1242/jcs.055566] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The conserved Aurora B protein kinase (Ipl1 in Saccharomyces cerevisiae) is essential for ensuring that sister kinetochores become attached to microtubules from opposite spindle poles (bi-orientation) before anaphase onset. When sister chromatids become attached to microtubules from a single pole, Aurora B/Ipl1 facilitates turnover of kinetochore-microtubule attachments. This process requires phosphorylation by Aurora B/Ipl1 of kinetochore components such as Dam1 in yeast. Once bi-orientation is established and tension is applied on kinetochores, Aurora B/Ipl1 must stop promoting this turnover, otherwise correct attachment would never be stabilised. How this is achieved remains elusive: it might be due to dephosphorylation of Aurora B/Ipl1 substrates at kinetochores, or might take place independently, for example because of conformational changes in kinetochores. Here, we show that Ipl1-dependent phosphorylation at crucial sites on Dam1 is maximal during S phase and minimal during metaphase, matching the cell cycle window when chromosome bi-orientation occurs. Intriguingly, when we reduced tension at kinetochores through failure to establish sister chromatid cohesion, Dam1 phosphorylation persisted in metaphase-arrested cells. We propose that Aurora B/Ipl1-facilitated bi-orientation is stabilised in response to tension at kinetochores by dephosphorylation of Dam1, resulting in termination of kinetochore-microtubule attachment turnover.
Collapse
Affiliation(s)
- Patrick Keating
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, MSI/WTB Complex, University of Dundee, Dundee, DD1 5EH, UK
| | | | | | | |
Collapse
|
29
|
Ng TM, Waples WG, Lavoie BD, Biggins S. Pericentromeric sister chromatid cohesion promotes kinetochore biorientation. Mol Biol Cell 2009; 20:3818-27. [PMID: 19605555 DOI: 10.1091/mbc.e09-04-0330] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Accurate chromosome segregation depends on sister kinetochores making bioriented attachments to microtubules from opposite poles. An essential regulator of biorientation is the Ipl1/Aurora B protein kinase that destabilizes improper microtubule-kinetochore attachments. To identify additional biorientation pathways, we performed a systematic genetic analysis between the ipl1-321 allele and all nonessential budding yeast genes. One of the mutants, mcm21Delta, precociously separates pericentromeres and this is associated with a defect in the binding of the Scc2 cohesin-loading factor at the centromere. Strikingly, Mcm21 becomes essential for biorientation when Ipl1 function is reduced, and this appears to be related to its role in pericentromeric cohesion. When pericentromeres are artificially tethered, Mcm21 is no longer needed for biorientation despite decreased Ipl1 activity. Taken together, these data reveal a specific role for pericentromeric linkage in ensuring kinetochore biorientation.
Collapse
Affiliation(s)
- Tessie M Ng
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | | | | |
Collapse
|
30
|
Efficient chromosome biorientation and the tension checkpoint in Saccharomyces cerevisiae both require Bir1. Mol Cell Biol 2009; 29:4552-62. [PMID: 19528231 DOI: 10.1128/mcb.01911-08] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Accurate chromosome segregation requires the capture of sister kinetochores by microtubules from opposite spindle poles prior to the initiation of anaphase, a state termed chromosome biorientation. In the budding yeast Saccharomyces cerevisiae, the conserved protein kinase Ipl1 (Aurora B in metazoans) is critical for ensuring correct chromosomal alignment. Ipl1 associates with its activators Sli15 (INCENP), Nbl1 (Borealin), and Bir1 (Survivin), but while Sli15 clearly functions with Ipl1 to promote chromosome biorientation, the role of Bir1 has been uncertain. Using a temperature-sensitive bir1 mutant (bir1-17), we show that Bir1 is needed to permit efficient chromosome biorientation. However, once established, chromosome biorientation is maintained in bir1-17 cells at the restrictive temperature. Ipl1 is partially delocalized in bir1-17 cells, and its protein kinase activity is markedly reduced under nonpermissive conditions. bir1-17 cells arrest normally in response to microtubule depolymerization but fail to delay anaphase when sister kinetochore tension is reduced. Thus, Bir1 is required for the tension checkpoint. Despite their robust mitotic arrest in response to nocodazole, bir1-17 cells are hypersensitive to microtubule-depolymerizing drugs and show a more severe biorientation defect on recovery from nocodazole treatment. The role of Bir1 therefore may become more critical when spindle formation is delayed.
Collapse
|
31
|
Abstract
DNA topoisomerases are enzymes that disentangle the topological problems that arise in double-stranded DNA. Many of these can be solved by the generation of either single or double strand breaks. However, where there is a clear requirement to alter DNA topology by introducing transient double strand breaks, only DNA topoisomerase II (TOP2) can carry out this reaction. Extensive biochemical and structural studies have provided detailed models of how TOP2 alters DNA structure, and recent molecular studies have greatly expanded knowledge of the biological contexts in which TOP2 functions, such as DNA replication, transcription and chromosome segregation -- processes that are essential for preventing tumorigenesis.
Collapse
Affiliation(s)
- John L Nitiss
- Molecular Pharmacology Department, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
| |
Collapse
|
32
|
Nakajima Y, Tyers RG, Wong CCL, Yates JR, Drubin DG, Barnes G. Nbl1p: a Borealin/Dasra/CSC-1-like protein essential for Aurora/Ipl1 complex function and integrity in Saccharomyces cerevisiae. Mol Biol Cell 2009; 20:1772-84. [PMID: 19158380 DOI: 10.1091/mbc.e08-10-1011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The Aurora kinase complex, also called the chromosomal passenger complex (CPC), is essential for faithful chromosome segregation and completion of cell division. In Fungi and Animalia, this complex consists of the kinase Aurora B/AIR-2/Ipl1p, INCENP/ICP-1/Sli15p, and Survivin/BIR-1/Bir1p. A fourth subunit, Borealin/Dasra/CSC-1, is required for CPC targeting to centromeres and central spindles and has only been found in Animalia. Here we identified a new core component of the CPC in budding yeast, Nbl1p. NBL1 is essential for viability and nbl1 mutations cause chromosome missegregation and lagging chromosomes. Nbl1p colocalizes and copurifies with the CPC, and it is essential for CPC localization, stability, integrity, and function. Nbl1p is related to the N-terminus of Borealin/Dasra/CSC-1 and is similarly involved in connecting the other CPC subunits. Distant homology searching identified nearly 200, mostly unannotated, Borealin/Dasra/CSC-1-related proteins from nearly 150 species within Fungi and Animalia. Analysis of the sequence of these proteins, combined with comparative protein structure modeling of Bir1p-Nbl1p-Sli15p using the crystal structure of the human Survivin-Borealin-INCENP complex, revealed a striking structural conservation across a broad range of species. Our biological and computational analyses therefore establish that the fundamental design of the CPC is conserved from Fungi to Animalia.
Collapse
Affiliation(s)
- Yuko Nakajima
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
| | | | | | | | | | | |
Collapse
|