1
|
Rizzo M, Soisangwan N, Vega-Estevez S, Price RJ, Uyl C, Iracane E, Shaw M, Soetaert J, Selmecki A, Buscaino A. Stress combined with loss of the Candida albicans SUMO protease Ulp2 triggers selection of aneuploidy via a two-step process. PLoS Genet 2022; 18:e1010576. [PMID: 36574460 PMCID: PMC9829183 DOI: 10.1371/journal.pgen.1010576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 01/09/2023] [Accepted: 12/16/2022] [Indexed: 12/29/2022] Open
Abstract
A delicate balance between genome stability and instability ensures genome integrity while generating genetic diversity, a critical step for evolution. Indeed, while excessive genome instability is harmful, moderated genome instability can drive adaptation to novel environments by maximising genetic variation. Candida albicans, a human fungal pathogen that colonises different parts of the human body, adapts rapidly and frequently to different hostile host microenvironments. In this organism, the ability to generate large-scale genomic variation is a key adaptative mechanism triggering dangerous infections even in the presence of antifungal drugs. Understanding how fitter novel karyotypes are selected is key to determining how C. albicans and other microbial pathogens establish infections. Here, we identified the SUMO protease Ulp2 as a regulator of C. albicans genome integrity through genetic screening. Deletion of ULP2 leads to increased genome instability, enhanced genome variation and reduced fitness in the absence of additional stress. The combined stress caused by the lack of ULP2 and antifungal drug treatment leads to the selection of adaptive segmental aneuploidies that partially rescue the fitness defects of ulp2Δ/Δ cells. Short and long-read genomic sequencing demonstrates that these novel genotypes are selected via a two-step process leading to the formation of novel chromosomal fragments with breakpoints at microhomology regions and DNA repeats.
Collapse
Affiliation(s)
- Marzia Rizzo
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
| | - Natthapon Soisangwan
- University of Minnesota, Department of Microbiology and Immunology, Minneapolis, Minnesota, United States of America
| | - Samuel Vega-Estevez
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
| | | | - Chloe Uyl
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
| | - Elise Iracane
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
| | - Matt Shaw
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
| | - Jan Soetaert
- Blizard Advanced Light Microscopy (BALM), Queen Mary University of London, United Kingdom
| | - Anna Selmecki
- University of Minnesota, Department of Microbiology and Immunology, Minneapolis, Minnesota, United States of America
| | - Alessia Buscaino
- University of Kent, School of Biosciences, Kent Fungal Group, Canterbury Kent, United Kingdom
- * E-mail:
| |
Collapse
|
2
|
Kumar S, Schoonderwoerd MJA, Kroonen JS, de Graaf IJ, Sluijter M, Ruano D, González-Prieto R, Verlaan-de Vries M, Rip J, Arens R, de Miranda NFCC, Hawinkels LJAC, van Hall T, Vertegaal ACO. Targeting pancreatic cancer by TAK-981: a SUMOylation inhibitor that activates the immune system and blocks cancer cell cycle progression in a preclinical model. Gut 2022; 71:2266-2283. [PMID: 35074907 PMCID: PMC9554032 DOI: 10.1136/gutjnl-2021-324834] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 12/29/2021] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Pancreatic ductal adenocarcinoma (PDAC) has the characteristics of high-density desmoplastic stroma, a distinctive immunosuppressive microenvironment and is profoundly resistant to all forms of chemotherapy and immunotherapy, leading to a 5-year survival rate of 9%. Our study aims to add novel small molecule therapeutics for the treatment of PDAC. DESIGN We have studied whether TAK-981, a novel highly selective and potent small molecule inhibitor of the small ubiquitin like modifier (SUMO) activating enzyme E1 could be used to treat a preclinical syngeneic PDAC mouse model and we have studied the mode of action of TAK-981. RESULTS We found that SUMOylation, a reversible post-translational modification required for cell cycle progression, is increased in PDAC patient samples compared with normal pancreatic tissue. TAK-981 decreased SUMOylation in PDAC cells at the nanomolar range, thereby causing a G2/M cell cycle arrest, mitotic failure and chromosomal segregation defects. TAK-981 efficiently limited tumour burden in the KPC3 syngeneic mouse model without evidence of systemic toxicity. In vivo treatment with TAK-981 enhanced the proportions of activated CD8 T cells and natural killer (NK) cells but transiently decreased B cell numbers in tumour, peripheral blood, spleen and lymph nodes. Single cell RNA sequencing revealed activation of the interferon response on TAK-981 treatment in lymphocytes including T, B and NK cells. TAK-981 treatment of CD8 T cells ex vivo induced activation of STAT1 and interferon target genes. CONCLUSION Our findings indicate that pharmacological inhibition of the SUMO pathway represents a potential strategy to target PDAC via a dual mechanism: inhibiting cancer cell cycle progression and activating anti-tumour immunity by inducing interferon signalling.
Collapse
Affiliation(s)
- Sumit Kumar
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Jessie S Kroonen
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ilona J de Graaf
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Marjolein Sluijter
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Dina Ruano
- Pathology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Román González-Prieto
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Jasper Rip
- Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ramon Arens
- Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - Thorbald van Hall
- Department of Medical Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Alfred C O Vertegaal
- Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
3
|
K6-linked SUMOylation of BAF regulates nuclear integrity and DNA replication in mammalian cells. Proc Natl Acad Sci U S A 2020; 117:10378-10387. [PMID: 32332162 PMCID: PMC7229763 DOI: 10.1073/pnas.1912984117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Barrier-to-autointegration factor (BAF) is a highly conserved protein in metazoans that has multiple functions during the cell cycle. We found that BAF is SUMOylated at K6, and that this modification is essential for its nuclear localization and function, including nuclear integrity maintenance and DNA replication. K6-linked SUMOylation of BAF promotes binding and interaction with lamin A/C to regulate nuclear integrity. K6-linked SUMOylation of BAF also supports BAF binding to DNA and proliferating cell nuclear antigen and regulates DNA replication. SENP1 and SENP2 catalyze the de-SUMOylation of BAF at K6. Disrupting the SUMOylation and de-SUMOylation cycle of BAF at K6 not only disturbs nuclear integrity, but also induces DNA replication failure. Taken together, our findings demonstrate that SUMOylation at K6 is an important regulatory mechanism that governs the nuclear functions of BAF in mammalian cells.
Collapse
|
4
|
Break-induced replication promotes formation of lethal joint molecules dissolved by Srs2. Nat Commun 2017; 8:1790. [PMID: 29176630 PMCID: PMC5702615 DOI: 10.1038/s41467-017-01987-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/27/2017] [Indexed: 12/20/2022] Open
Abstract
Break-induced replication (BIR) is a DNA double-strand break repair pathway that leads to genomic instabilities similar to those observed in cancer. BIR proceeds by a migrating bubble where asynchrony between leading and lagging strand synthesis leads to accumulation of long single-stranded DNA (ssDNA). It remains unknown how this ssDNA is prevented from unscheduled pairing with the template, which can lead to genomic instability. Here, we propose that uncontrolled Rad51 binding to this ssDNA promotes formation of toxic joint molecules that are counteracted by Srs2. First, Srs2 dislodges Rad51 from ssDNA preventing promiscuous strand invasions. Second, it dismantles toxic intermediates that have already formed. Rare survivors in the absence of Srs2 rely on structure-specific endonucleases, Mus81 and Yen1, that resolve toxic joint-molecules. Overall, we uncover a new feature of BIR and propose that tight control of ssDNA accumulated during this process is essential to prevent its channeling into toxic structures threatening cell viability. Break-induced replication (BIR) is a double-strand break repair pathway that can lead to genomic instability. Here the authors show that the absence of Srs2 helicase during BIR leads to uncontrolled binding of Rad51 to single-stranded DNA, which promotes the formation of toxic intermediates that need to be resolved by Mus81 or Yen1.
Collapse
|
5
|
Reversible regulation of ORC2 SUMOylation by PIAS4 and SENP2. Oncotarget 2017; 8:70142-70155. [PMID: 29050267 PMCID: PMC5642542 DOI: 10.18632/oncotarget.19594] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 06/20/2017] [Indexed: 01/14/2023] Open
Abstract
The small ubiquitin-related modifier (SUMO) system is essential for smooth progression of cell cycle at the G2/M phase. Many centromeric proteins are reversibly SUMOylated to ensure proper chromosome segregation at the mitosis. SUMOylation of centromeric Origin Recognition Complex subunit 2 (ORC2) at the G2/M phase is essential in maintaining genome integrity. However, how ORC2 SUMOylation is regulated remains largely unclear. Here we show that ORC2 SUMOylation is reversibly controlled by SUMO E3 ligase PIAS4 and De-SUMOylase SENP2. Either depletion of PIAS4 or overexpression of SENP2 eliminated SUMOylation of ORC2 at the G/M phase and consequently resulted in abnormal centromeric histone H3 lysine 4 methylation. Cells stably expressing SENP2 protein or small interfering RNA for PIAS4 bypassed mitosis and endoreduplicated their genome to become polyploidy. Furthermore, percentage of polyploid cells is reduced after coexpression of ORC2-SUMO2 fusion protein. Thus, the proper regulation of ORC2 SUMOylation at the G2/M phase by PIAS4 and SENP2 is critical for smooth progression of the mitotic cycle of cells.
Collapse
|
6
|
Jongjitwimol J, Baldock RA, Morley SJ, Watts FZ. Sumoylation of eIF4A2 affects stress granule formation. J Cell Sci 2016; 129:2407-15. [PMID: 27160682 PMCID: PMC4920252 DOI: 10.1242/jcs.184614] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/29/2016] [Indexed: 01/27/2023] Open
Abstract
Regulation of protein synthesis is crucial for cells to maintain viability and to prevent unscheduled proliferation that could lead to tumorigenesis. Exposure to stress results in stalling of translation, with many translation initiation factors, ribosomal subunits and mRNAs being sequestered into stress granules or P bodies. This allows the re-programming of the translation machinery. Many aspects of translation are regulated by post-translational modification. Several proteomic screens have identified translation initiation factors as targets for sumoylation, although in many cases the role of this modification has not been determined. We show here that eIF4A2 is modified by SUMO, with sumoylation occurring on a single residue (K226). We demonstrate that sumoylation of eIF4A2 is modestly increased in response to arsenite and ionising radiation, but decreases in response to heat shock or hippuristanol. In arsenite-treated cells, but not in hippuristanol-treated cells, eIF4A2 is recruited to stress granules, suggesting sumoylation of eIF4A2 correlates with its recruitment to stress granules. Furthermore, we demonstrate that the inability to sumoylate eIF4A2 results in impaired stress granule formation, indicating a new role for sumoylation in the stress response. Summary: In response to stress, proteins required to initiate protein synthesis are modified; we demonstrate that sumoylation of eIF4A2 correlates with its recruitment to stress granules.
Collapse
Affiliation(s)
- Jirapas Jongjitwimol
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Robert A Baldock
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Simon J Morley
- Department of Biochemistry and Biomedical Science, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Felicity Z Watts
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| |
Collapse
|
7
|
Huang C, Cheng J, Bawa-Khalfe T, Yao X, Chin YE, Yeh ETH. SUMOylated ORC2 Recruits a Histone Demethylase to Regulate Centromeric Histone Modification and Genomic Stability. Cell Rep 2016; 15:147-157. [PMID: 27052177 DOI: 10.1016/j.celrep.2016.02.091] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 12/17/2015] [Accepted: 02/26/2016] [Indexed: 01/25/2023] Open
Abstract
Origin recognition complex 2 (ORC2), a subunit of the ORC, is essential for DNA replication initiation in eukaryotic cells. In addition to a role in DNA replication initiation at the G1/S phase, ORC2 has been shown to localize to the centromere during the G2/M phase. Here, we show that ORC2 is modified by small ubiquitin-like modifier 2 (SUMO2), but not SUMO1, at the G2/M phase of the cell cycle. SUMO2-modification of ORC2 is important for the recruitment of KDM5A in order to convert H3K4me3 to H3K4me2, a "permissive" histone marker for α-satellite transcription at the centromere. Persistent expression of SUMO-less ORC2 led to reduced α-satellite transcription and impaired pericentric heterochromatin silencing, which resulted in re-replication of heterochromatin DNA. DNA re-replication eventually activated the DNA damage response, causing the bypass of mitosis and the formation of polyploid cells. Thus, ORC2 sustains genomic stability by recruiting KDM5A to maintain centromere histone methylation in order to prevent DNA re-replication.
Collapse
Affiliation(s)
- Chao Huang
- Texas Heart Institute, Houston, TX 77030, USA; Department of Cardiology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA; The Central Lab at Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jinke Cheng
- Texas Heart Institute, Houston, TX 77030, USA; Department of Biochemistry and Molecular and Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Tasneem Bawa-Khalfe
- Department of Cardiology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA; Center for Nuclear Receptors and Cell Signaling and Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA
| | - Xuebiao Yao
- Anhui Key Laboratory of Cellular Dynamics and Hefei National Laboratory for Physical Sciences at Nanoscale, University of Science and Technology of China, Hefei 230026, China
| | - Y Eugene Chin
- The Central Lab at Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Edward T H Yeh
- Texas Heart Institute, Houston, TX 77030, USA; Department of Cardiology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
| |
Collapse
|
8
|
Xu HD, Shi SP, Chen X, Qiu JD. Systematic Analysis of the Genetic Variability That Impacts SUMO Conjugation and Their Involvement in Human Diseases. Sci Rep 2015; 5:10900. [PMID: 26154679 PMCID: PMC4495600 DOI: 10.1038/srep10900] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 05/05/2015] [Indexed: 12/12/2022] Open
Abstract
Protein function has been observed to rely on select essential sites instead of requiring all sites to be indispensable. Small ubiquitin-related modifier (SUMO) conjugation or sumoylation, which is a highly dynamic reversible process and its outcomes are extremely diverse, ranging from changes in localization to altered activity and, in some cases, stability of the modified, has shown to be especially valuable in cellular biology. Motivated by the significance of SUMO conjugation in biological processes, we report here on the first exploratory assessment whether sumoylation related genetic variability impacts protein functions as well as the occurrence of diseases related to SUMO. Here, we defined the SUMOAMVR as sumoylation related amino acid variations that affect sumoylation sites or enzymes involved in the process of connectivity, and categorized four types of potential SUMOAMVRs. We detected that 17.13% of amino acid variations are potential SUMOAMVRs and 4.83% of disease mutations could lead to SUMOAMVR with our system. More interestingly, the statistical analysis demonstrates that the amino acid variations that directly create new potential lysine sumoylation sites are more likely to cause diseases. It can be anticipated that our method can provide more instructive guidance to identify the mechanisms of genetic diseases.
Collapse
Affiliation(s)
- Hao-Dong Xu
- Department of Chemistry, Nanchang University, Nanchang 330031, P.R.China
| | - Shao-Ping Shi
- Department of Mathematics, Nanchang University, Nanchang 330031, P.R.China
| | - Xiang Chen
- Department of Chemistry, Nanchang University, Nanchang 330031, P.R.China
| | - Jian-Ding Qiu
- 1] Department of Chemistry, Nanchang University, Nanchang 330031, P.R.China [2] Department of Materials and Chemical Engineering, Pingxiang College, Pingxiang 337055, P.R.China
| |
Collapse
|
9
|
Sridharan V, Park H, Ryu H, Azuma Y. SUMOylation regulates polo-like kinase 1-interacting checkpoint helicase (PICH) during mitosis. J Biol Chem 2015; 290:3269-76. [PMID: 25564610 DOI: 10.1074/jbc.c114.601906] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mitotic SUMOylation has an essential role in faithful chromosome segregation in eukaryotes, although its molecular consequences are not yet fully understood. In Xenopus egg extract assays, we showed that poly(ADP-ribose) polymerase 1 (PARP1) is modified by SUMO2/3 at mitotic centromeres and that its enzymatic activity could be regulated by SUMOylation. To determine the molecular consequence of mitotic SUMOylation, we analyzed SUMOylated PARP1-specific binding proteins. We identified Polo-like kinase 1-interacting checkpoint helicase (PICH) as an interaction partner of SUMOylated PARP1 in Xenopus egg extract. Interestingly, PICH also bound to SUMOylated topoisomerase IIα (TopoIIα), a major centromeric small ubiquitin-like modifier (SUMO) substrate. Purified recombinant human PICH interacted with SUMOylated substrates, indicating that PICH directly interacts with SUMO, and this interaction is conserved among species. Further analysis of mitotic chromosomes revealed that PICH localized to the centromere independent of mitotic SUMOylation. Additionally, we found that PICH is modified by SUMO2/3 on mitotic chromosomes and in vitro. PICH SUMOylation is highly dependent on protein inhibitor of activated STAT, PIASy, consistent with other mitotic chromosomal SUMO substrates. Finally, the SUMOylation of PICH significantly reduced its DNA binding capability, indicating that SUMOylation might regulate its DNA-dependent ATPase activity. Collectively, our findings suggest a novel SUMO-mediated regulation of the function of PICH at mitotic centromeres.
Collapse
Affiliation(s)
- Vinidhra Sridharan
- From the Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045
| | - Hyewon Park
- From the Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045
| | - Hyunju Ryu
- From the Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045
| | - Yoshiaki Azuma
- From the Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045
| |
Collapse
|
10
|
Yavuz AS, Sezerman OU. Predicting sumoylation sites using support vector machines based on various sequence features, conformational flexibility and disorder. BMC Genomics 2014; 15 Suppl 9:S18. [PMID: 25521314 PMCID: PMC4290605 DOI: 10.1186/1471-2164-15-s9-s18] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sumoylation, which is a reversible and dynamic post-translational modification, is one of the vital processes in a cell. Before a protein matures to perform its function, sumoylation may alter its localization, interactions, and possibly structural conformation. Abberations in protein sumoylation has been linked with a variety of disorders and developmental anomalies. Experimental approaches to identification of sumoylation sites may not be effective due to the dynamic nature of sumoylation, laborsome experiments and their cost. Therefore, computational approaches may guide experimental identification of sumoylation sites and provide insights for further understanding sumoylation mechanism. RESULTS In this paper, the effectiveness of using various sequence properties in predicting sumoylation sites was investigated with statistical analyses and machine learning approach employing support vector machines. These sequence properties were derived from windows of size 7 including position-specific amino acid composition, hydrophobicity, estimated sub-window volumes, predicted disorder, and conformational flexibility. 5-fold cross-validation results on experimentally identified sumoylation sites revealed that our method successfully predicts sumoylation sites with a Matthew's correlation coefficient, sensitivity, specificity, and accuracy equal to 0.66, 73%, 98%, and 97%, respectively. Additionally, we have showed that our method compares favorably to the existing prediction methods and basic regular expressions scanner. CONCLUSIONS By using support vector machines, a new, robust method for sumoylation site prediction was introduced. Besides, the possible effects of predicted conformational flexibility and disorder on sumoylation site recognition were explored computationally for the first time to our knowledge as an additional parameter that could aid in sumoylation site prediction.
Collapse
|
11
|
Ma L, Aslanian A, Sun H, Jin M, Shi Y, Yates JR, Hunter T. Identification of small ubiquitin-like modifier substrates with diverse functions using the Xenopus egg extract system. Mol Cell Proteomics 2014; 13:1659-75. [PMID: 24797264 DOI: 10.1074/mcp.m113.035626] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Post-translational modification by SUMO is a highly conserved pathway in eukaryotes that plays very important regulatory roles in many cellular processes. Deregulation of the SUMO pathway contributes to the development and progression of many diseases including cancer. Therefore, identifying additional SUMO substrates and studying how their cellular and biological functions are regulated by sumoylation should provide new insights. Our studies showed that sumoylation activity was significant in Xenopus egg extracts, and that a high level of sumoylation was associated with sperm chromatin when SUMO was incubated with Xenopus egg extracts. By isolating SUMO-conjugated substrates using His-tagged SUMO1 or SUMO2 proteins under denaturing conditions, we identified 346 proteins by mass spectrometry analysis that were not present in control pull-downs. Among them, 167 proteins were identified from interphase egg extracts, 86 proteins from mitotic phase egg extracts, and 93 proteins from both. Thirty-three proteins were pulled down by SUMO1, 85 proteins by SUMO2, and 228 proteins by both. We validated the sumoylation of five candidates, CKB, ATXN10, BTF3, HABP4, and BZW1, by co-transfecting them along with SUMO in HEK293T cells. Gene ontology analysis showed that SUMO substrates identified in this study were involved in diverse biological processes. Additionally, SUMO substrates identified from different cell cycle stages or pulled down by different SUMO homologs were enriched for distinct cellular components and functional categories. Our results comprehensively profile the sumoylation occurring in the Xenopus egg extract system.
Collapse
Affiliation(s)
- Li Ma
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Aaron Aslanian
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA; §Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Huaiyu Sun
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Mingji Jin
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Yu Shi
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - John R Yates
- §Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Tony Hunter
- From the ‡Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA;
| |
Collapse
|
12
|
Hu H, Yu Z, Liu Y, Wang T, Wei Y, Li Z. The Aurora B kinase in Trypanosoma brucei undergoes post-translational modifications and is targeted to various subcellular locations through binding to TbCPC1. Mol Microbiol 2013; 91:256-74. [PMID: 24224936 DOI: 10.1111/mmi.12458] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2013] [Indexed: 11/30/2022]
Abstract
The chromosomal passenger complex (CPC) in animals, consisting of Aurora B kinase and three evolutionarily conserved proteins, plays crucial roles in mitosis and cytokinesis. However, Trypanosoma brucei expresses an unusual CPC consisting of an Aurora-like kinase, TbAUK1, and two kinetoplastid-specific proteins, TbCPC1 and TbCPC2. Despite their essential functions, little is known about the regulation of TbAUK1 and the roles of TbCPC1 and TbCPC2. Here, we investigate the effect of post-translational modification on the activity and spatiotemporal control of TbAUK1, and demonstrate that phosphorylation of two conserved threonine residues in the activation loop of the kinase domain contributes to TbAUK1 activation and function. TbAUK1 is SUMOylated in vivo, and mutation of the SUMO-conjugation site compromises TbAUK1 function. Degradation of TbAUK1 requires two destruction boxes and is mediated by the anaphase-promoting complex/cyclosome (APC/C), whereas degradation of TbCPC1 and TbCPC2 is not dependent on the predicted destruction boxes and is APC/C-independent. Moreover, we determine the domains in CPC subunits that mediate the pairwise interactions, and show that disruption of the interaction impairs the localization of TbAUK1 and TbCPC2 but not TbCPC1. Our results demonstrate the requirement of post-translational modifications for TbAUK1 function and a crucial role of TbCPC1 in mediating TbAUK1 localization.
Collapse
Affiliation(s)
- Huiqing Hu
- Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, Houston, TX, 77030, USA
| | | | | | | | | | | |
Collapse
|
13
|
Ijaz A. SUMOhunt: Combining Spatial Staging between Lysine and SUMO with Random Forests to Predict SUMOylation. ISRN BIOINFORMATICS 2013; 2013:671269. [PMID: 25937950 PMCID: PMC4393069 DOI: 10.1155/2013/671269] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 05/28/2013] [Indexed: 11/20/2022]
Abstract
Modification with SUMO protein has many key roles in eukaryotic systems which renders the identification of its target proteins and sites of considerable importance. Information regarding the SUMOylation of a protein may tell us about its subcellular localization, function, and spatial orientation. This modification occurs at particular and not all lysine residues in a given protein. In competition with biochemical means of modified-site recognition, computational methods are strong contenders in the prediction of SUMOylation-undergoing sites on proteins. In this research, physicochemical properties of amino acids retrieved from AAIndex, especially those involved in docking of modifier and target proteins and optimal presentation of target lysine, in combination with sequence information and random forest-based classifier presented in WEKA have been used to develop a prediction model, SUMOhunt, with statistics significantly better than all previous predictors. In this model 97.56% accuracy, 100% sensitivity, 94% specificity, and 0.95 MCC have been achieved which shows that proposed amino acid properties have a significant role in SUMO attachment. SUMOhunt will hence bring great reliability and efficiency in SUMOylation prediction.
Collapse
Affiliation(s)
- Amna Ijaz
- National Institute of Biotechnology and Genetic Engineering, P.O. Box 577, Jhang Road, Faisalabad, Pakistan
| |
Collapse
|
14
|
Peluso JJ. Progesterone receptor membrane component 1 and its role in ovarian follicle growth. Front Neurosci 2013; 7:99. [PMID: 23781168 PMCID: PMC3680780 DOI: 10.3389/fnins.2013.00099] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 05/22/2013] [Indexed: 12/11/2022] Open
Abstract
Progesterone (P4) is synthesized in the ovary and acts directly on granulosa cells of developing ovarian follicles to suppress their rate of mitosis and apoptosis. Granulosa cells do not express nuclear progesterone receptor (PGR) but rather progesterone receptor membrane component-1 (PGRMC1). PGRMC1 binds P4 and mediates P4's actions, as evidenced by PGRMC1 siRNA studies. PGRMC1 acts by binding plasminogen activator inhibitor 1 RNA-binding protein and regulating gene expression. Specifically, PGRMC1 suppresses some genes that promote cell death (i.e., Bad, Caspase-3, Caspase-4). P4 regulates gene expression in part by inhibiting PGRMC1 binding to Tcf/Lef transcription sites, thereby reducing Tcf/Lef transcriptional activity. Since Tcf/Lef transcription sites are located within the promoters of genes that initiate mitosis and/or apoptosis (i.e., c-jun and c-myc), P4-PGRMC1 mediated suppression of these Tcf/Lef regulated genes could account for P4's actions. PGRMC1 expression is also altered in women with polycystic ovarian syndrome, premature ovarian failure and infertility. Collectively, these observations support a role for PGRMC1 in regulating human ovarian follicle development.
Collapse
Affiliation(s)
- John J Peluso
- Department of Cell Biology, University of Connecticut Health Center Farmington CT, USA ; Department of Obstetrics and Gynecology, University of Connecticut Health Center Farmington CT, USA
| |
Collapse
|
15
|
Wan J, Subramonian D, Zhang XD. SUMOylation in control of accurate chromosome segregation during mitosis. Curr Protein Pept Sci 2013; 13:467-81. [PMID: 22812528 PMCID: PMC3474960 DOI: 10.2174/138920312802430563] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 02/26/2012] [Accepted: 06/11/2012] [Indexed: 12/15/2022]
Abstract
Posttranslational protein modification by small ubiquitin-related modifier (SUMO) has emerged as an important regulatory mechanism for chromosome segregation during mitosis. This review focuses on how SUMOylation regulates the centromere and kinetochore activities to achieve accurate chromosome segregation during mitosis. Kinetochores are assembled on the specialized chromatin domains called centromeres and serve as the sites for attaching spindle microtubule to segregate sister chromatids to daughter cells. Many proteins associated with mitotic centromeres and kinetochores have been recently found to be modified by SUMO. Although we are still at the early stage of elucidating how SUMOylation controls chromosome segregation during mitosis, a substantial progress has been achieved over the past decade. Furthermore, a major theme that has emerged from the recent studies of SUMOylation in mitosis is that both SUMO conjugation and deconjugation are critical for kinetochore assembly and disassembly. Lastly, we propose a model that SUMOylation coordinates multiple centromere and kinetochore activities to ensure accurate chromosome segregation.
Collapse
Affiliation(s)
- Jun Wan
- Department of Biological Sciences, Wayne State University, Detroit, Michigan 48202, USA
| | | | | |
Collapse
|
16
|
Liu HW, Zhang J, Heine GF, Arora M, Gulcin Ozer H, Onti-Srinivasan R, Huang K, Parvin JD. Chromatin modification by SUMO-1 stimulates the promoters of translation machinery genes. Nucleic Acids Res 2012; 40:10172-86. [PMID: 22941651 PMCID: PMC3488252 DOI: 10.1093/nar/gks819] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
SUMOylation of transcription factors and chromatin proteins is in many cases a negative mark that recruits factors that repress gene expression. In this study, we determined the occupancy of Small Ubiquitin-like MOdifier (SUMO)-1 on chromatin in HeLa cells by use of chromatin affinity purification coupled with next-generation sequencing. We found SUMO-1 localization on chromatin was dynamic throughout the cell cycle. Surprisingly, we observed that from G1 through late S phase, but not during mitosis, SUMO-1 marks the chromatin just upstream of the transcription start site on many of the most active housekeeping genes, including genes encoding translation factors and ribosomal subunit proteins. Moreover, we found that SUMO-1 distribution on promoters was correlated with H3K4me3, another general chromatin activation mark. Depletion of SUMO-1 resulted in downregulation of the genes that were marked by SUMO-1 at their promoters during interphase, supporting the concept that the marking of promoters by SUMO-1 is associated with transcriptional activation of genes involved in ribosome biosynthesis and in the protein translation process.
Collapse
Affiliation(s)
- Hui-wen Liu
- The Department of Biomedical Informatics and the Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Expression characteristics of the SUMOylation genes SUMO-1 and Ubc9 in the developing testis and ovary of Chinese mitten crab, Eriocheir sinensis. Gene 2012; 501:135-43. [DOI: 10.1016/j.gene.2012.04.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 03/19/2012] [Accepted: 04/05/2012] [Indexed: 11/30/2022]
|
18
|
Pérez de Castro I, Aguirre-Portolés C, Martin B, Fernández-Miranda G, Klotzbucher A, Kubbutat MHG, Megías D, Arlot-Bonnemains Y, Malumbres M. A SUMOylation Motif in Aurora-A: Implications for Spindle Dynamics and Oncogenesis. Front Oncol 2011; 1:50. [PMID: 22649767 PMCID: PMC3355891 DOI: 10.3389/fonc.2011.00050] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 11/22/2011] [Indexed: 11/13/2022] Open
Abstract
Aurora-A is a serine/threonine kinase that plays critical roles in centrosome maturation, spindle dynamics, and chromosome orientation and it is frequently over-expressed in human cancers. In this work, we show that Aurora-A interacts with the SUMO-conjugating enzyme UBC9 and co-localizes with SUMO1 in mitotic cells. Aurora-A can be SUMOylated in vitro and in vivo. Mutation of the highly conserved SUMOylation residue lysine 249 significantly disrupts Aurora-A SUMOylation and mitotic defects characterized by defective and multipolar spindles ensue. The Aurora-AK249R mutant has normal kinase activity but displays altered dynamics at the mitotic spindle. In addition, ectopic expression of the Aurora-AK249R mutant results in a significant increase in susceptibility to malignant transformation induced by the Ras oncogene. These data suggest that modification by SUMO residues may control Aurora-A function at the spindle and that deficiency of SUMOylation of this kinase may have important implications for tumor development.
Collapse
Affiliation(s)
- Ignacio Pérez de Castro
- Molecular Oncology Programme, Cell Division and Cancer Group, Centro Nacional de Investigaciones Oncológicas Madrid, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Orelio C, van der Sluis RM, Verkuijlen P, Nethe M, Hordijk PL, van den Berg TK, Kuijpers TW. Altered intracellular localization and mobility of SBDS protein upon mutation in Shwachman-Diamond syndrome. PLoS One 2011; 6:e20727. [PMID: 21695142 PMCID: PMC3113850 DOI: 10.1371/journal.pone.0020727] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2010] [Accepted: 05/09/2011] [Indexed: 11/18/2022] Open
Abstract
Shwachman-Diamond Syndrome (SDS) is a rare inherited disease caused by mutations in the SBDS gene. Hematopoietic defects, exocrine pancreas dysfunction and short stature are the most prominent clinical features. To gain understanding of the molecular properties of the ubiquitously expressed SBDS protein, we examined its intracellular localization and mobility by live cell imaging techniques. We observed that SBDS full-length protein was localized in both the nucleus and cytoplasm, whereas patient-related truncated SBDS protein isoforms localize predominantly to the nucleus. Also the nucleo-cytoplasmic trafficking of these patient-related SBDS proteins was disturbed. Further studies with a series of SBDS mutant proteins revealed that three distinct motifs determine the intracellular mobility of SBDS protein. A sumoylation motif in the C-terminal domain, that is lacking in patient SBDS proteins, was found to play a pivotal role in intracellular motility. Our structure-function analyses provide new insight into localization and motility of the SBDS protein, and show that patient-related mutant proteins are altered in their molecular properties, which may contribute to the clinical features observed in SDS patients.
Collapse
Affiliation(s)
- Claudia Orelio
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Blood Cell Research, University of Amsterdam, Amsterdam, The Netherlands
| | - Renée M. van der Sluis
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Blood Cell Research, University of Amsterdam, Amsterdam, The Netherlands
| | - Paul Verkuijlen
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Blood Cell Research, University of Amsterdam, Amsterdam, The Netherlands
| | - Micha Nethe
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Molecular Cell Biology, University of Amsterdam, Amsterdam, The Netherlands
| | - Peter L. Hordijk
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Molecular Cell Biology, University of Amsterdam, Amsterdam, The Netherlands
| | - Timo K. van den Berg
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Blood Cell Research, University of Amsterdam, Amsterdam, The Netherlands
| | - Taco W. Kuijpers
- Sanquin Research and Landsteiner Laboratory of the Academic Medical Center (AMC), Department of Blood Cell Research, University of Amsterdam, Amsterdam, The Netherlands
- Emma Children's Hospital, Academic Medical Center (AMC), Amsterdam, The Netherlands
- * E-mail:
| |
Collapse
|
20
|
Ryu H, Furuta M, Kirkpatrick D, Gygi SP, Azuma Y. PIASy-dependent SUMOylation regulates DNA topoisomerase IIalpha activity. J Cell Biol 2010; 191:783-94. [PMID: 21079245 PMCID: PMC2983052 DOI: 10.1083/jcb.201004033] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Accepted: 10/13/2010] [Indexed: 11/30/2022] Open
Abstract
DNA topoisomerase IIα (TopoIIα) is an essential chromosome-associated enzyme with activity implicated in the resolution of tangled DNA at centromeres before anaphase onset. However, the regulatory mechanism of TopoIIα activity is not understood. Here, we show that PIASy-mediated small ubiquitin-like modifier 2/3 (SUMO2/3) modification of TopoIIα strongly inhibits TopoIIα decatenation activity. Using mass spectrometry and biochemical analysis, we demonstrate that TopoIIα is SUMOylated at lysine 660 (Lys660), a residue located in the DNA gate domain, where both DNA cleavage and religation take place. Remarkably, loss of SUMOylation on Lys660 eliminates SUMOylation-dependent inhibition of TopoIIα, which indicates that Lys660 SUMOylation is critical for PIASy-mediated inhibition of TopoIIα activity. Together, our findings provide evidence for the regulation of TopoIIα activity on mitotic chromosomes by SUMOylation. Therefore, we propose a novel mechanism for regulation of centromeric DNA catenation during mitosis by PIASy-mediated SUMOylation of TopoIIα.
Collapse
Affiliation(s)
- Hyunju Ryu
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045
| | - Maiko Furuta
- Laboratory of Gene Regulation and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | | | - Steven P. Gygi
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115
| | - Yoshiaki Azuma
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045
| |
Collapse
|
21
|
Elrouby N, Coupland G. Proteome-wide screens for small ubiquitin-like modifier (SUMO) substrates identify Arabidopsis proteins implicated in diverse biological processes. Proc Natl Acad Sci U S A 2010; 107:17415-20. [PMID: 20855607 PMCID: PMC2951436 DOI: 10.1073/pnas.1005452107] [Citation(s) in RCA: 142] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Covalent modification of proteins by small ubiquitin-like modifier (SUMO) regulates various cellular activities in yeast and mammalian cells. In Arabidopsis, inactivation of genes encoding SUMO or SUMO-conjugation enzymes is lethal, emphasizing the importance of SUMOylation in plant development. Despite this, little is known about SUMO targets in plants. Here we identified 238 Arabidopsis proteins as potential SUMO substrates because they interacted with SUMO-conjugating enzyme and/or SUMO protease (ESD4) in the yeast two-hybrid system. Compared with the whole Arabidopsis proteome, the identified proteins were strongly enriched for those containing high-probability consensus SUMO attachment sites, further supporting that they are true SUMO substrates. A high-throughput assay was developed in Escherichia coli and used to test the SUMOylation of 56% of these proteins. More than 92% of the proteins tested were SUMOylated in this assay by at least one SUMO isoform. Furthermore, ADA2b, an ESD4 interactor that was SUMOylated in the E. coli system, also was shown to be SUMOylated in Arabidopsis. The identified SUMO substrates are involved in a wide range of plant processes, many of which were not previously known to involve SUMOylation. These proteins provide a basis for exploring the function of SUMOylation in the regulation of diverse processes in Arabidopsis.
Collapse
Affiliation(s)
- Nabil Elrouby
- Max Planck Institute for Plant Breeding Research, Carl-von-Linne Weg 10, Cologne 50829, Germany
| | - George Coupland
- Max Planck Institute for Plant Breeding Research, Carl-von-Linne Weg 10, Cologne 50829, Germany
| |
Collapse
|
22
|
Boyd LK, Mercer B, Thompson D, Main E, Watts FZ. Characterisation of the SUMO-like domains of Schizosaccharomyces pombe Rad60. PLoS One 2010; 5:e13009. [PMID: 20885950 PMCID: PMC2946365 DOI: 10.1371/journal.pone.0013009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 08/24/2010] [Indexed: 11/25/2022] Open
Abstract
The S. pombe Rad60 protein is required for the repair of DNA double strand breaks, recovery from replication arrest, and is essential for cell viability. It has two SUMO-like domains (SLDs) at its C-terminus, an SXS motif and three sequences that have been proposed to be SUMO-binding motifs (SBMs). SMB1 is located in the middle of the protein, SBM2 is in SLD1 and SBM3 is at the C-terminus of SLD2. We have probed the functions of the two SUMO-like domains, SLD1 and SLD2, and the putative SBMs. SLD1 is essential for viability, while SLD2 is not. rad60-SLD2Δ cells are sensitive to DNA damaging agents and hydroxyurea. Neither ubiquitin nor SUMO can replace SLD1 or SLD2. Cells in which either SBM1 or SBM2 has been mutated are viable and are wild type for response to MMS and HU. In contrast mutation of SBM3 results in significant sensitivity to MMS and HU. These results indicate that the lethality resulting from deletion of SLD1 is not due to loss of SBM2, but that mutation of SBM3 produces a more severe phenotype than does deletion of SLD2. Using chemical denaturation studies, FPLC and dynamic light scattering we show this is likely due to the destabilisation of SLD2. Thus we propose that the region corresponding to the putative SBM3 forms part of the hydrophobic core of SLD2 and is not a SUMO-interacting motif. Over-expression of Hus5, which is the SUMO conjugating enzyme and known to interact with Rad60, does not rescue rad60-SLD2Δ, implying that as well as having a role in the sumoylation process as previously described [1], Rad60 has a Hus5-independent function.
Collapse
Affiliation(s)
- Lara K. Boyd
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Brenda Mercer
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Darren Thompson
- Division of Biochemistry and Biomedical Sciences, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Ewan Main
- Division of Chemistry, School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Felicity Z. Watts
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, United Kingdom
- * E-mail:
| |
Collapse
|
23
|
Obado SO, Bot C, Echeverry MC, Bayona JC, Alvarez VE, Taylor MC, Kelly JM. Centromere-associated topoisomerase activity in bloodstream form Trypanosoma brucei. Nucleic Acids Res 2010; 39:1023-33. [PMID: 20864447 PMCID: PMC3035458 DOI: 10.1093/nar/gkq839] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Topoisomerase-II accumulates at centromeres during prometaphase, where it resolves the DNA catenations that represent the last link between sister chromatids. Previously, using approaches including etoposide-mediated topoisomerase-II cleavage, we mapped centromeric domains in trypanosomes, early branching eukaryotes in which chromosome segregation is poorly understood. Here, we show that in bloodstream form Trypanosoma brucei, RNAi-mediated depletion of topoisomerase-IIα, but not topoisomerase-IIβ, results in the abolition of centromere-localized activity and is lethal. Both phenotypes can be rescued by expression of the corresponding enzyme from T. cruzi. Therefore, processes which govern centromere-specific topoisomerase-II accumulation/activation have been functionally conserved within trypanosomes, despite the long evolutionary separation of these species and differences in centromeric DNA organization. The variable carboxyl terminal region of topoisomerase-II has a major role in regulating biological function. We therefore generated T. brucei lines expressing T. cruzi topoisomerase-II truncated at the carboxyl terminus and examined activity at centromeres after the RNAi-mediated depletion of the endogenous enzyme. A region necessary for nuclear localization was delineated to six residues. In other organisms, sumoylation of topoisomerase-II has been shown to be necessary for regulated chromosome segregation. Evidence that we present here suggests that sumoylation of the T. brucei enzyme is not required for centromere-specific cleavage activity.
Collapse
Affiliation(s)
- Samson O Obado
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | | | | | | | | | | |
Collapse
|
24
|
Fernández-Miranda G, Pérez de Castro I, Carmena M, Aguirre-Portolés C, Ruchaud S, Fant X, Montoya G, Earnshaw WC, Malumbres M. SUMOylation modulates the function of Aurora-B kinase. J Cell Sci 2010; 123:2823-33. [PMID: 20663916 DOI: 10.1242/jcs.065565] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aurora kinases are central regulators of mitotic-spindle assembly, chromosome segregation and cytokinesis. Aurora B is a member of the chromosomal passenger complex (CPC) with crucial functions in regulation of the attachment of kinetochores to microtubules and in cytokinesis. We report here that Aurora B contains a conserved SUMO modification motif within its kinase domain. Aurora B can bind SUMO peptides in vitro when bound to the IN-box domain of its CPC partner INCENP. Mutation of Lys207 to arginine (Aurora B(K207R)) impairs the formation of conjugates of Aurora B and SUMO in vivo. Expression of the SUMO-null form of Aurora B results in abnormal chromosome segregation and cytokinesis failure and it is not able to rescue mitotic defects in Aurora-B-knockout cells. These defects are accompanied by increased levels of the CPC on chromosome arms and defective centromeric function, as detected by decreased phosphorylation of the Aurora-B substrate CENP-A. The Aurora-B(K207R) mutant does not display reduced kinase activity, suggesting that functional defects are probably a consequence of the altered localization, rather than decreased intrinsic kinase activity. These data suggest that SUMOylation of Aurora B modulates its function, possibly by mediating the extraction of CPC complexes from chromosome arms during prometaphase.
Collapse
|
25
|
Liao S, Wang T, Fan K, Tu X. The small ubiquitin-like modifier (SUMO) is essential in cell cycle regulation in Trypanosoma brucei. Exp Cell Res 2010; 316:704-15. [PMID: 20045687 DOI: 10.1016/j.yexcr.2009.12.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 12/17/2009] [Accepted: 12/18/2009] [Indexed: 01/18/2023]
Abstract
SUMO, a reversible post-translational protein modifier, plays important roles in many processes of higher eukaryotic cell life. Although SUMO has been identified in many eukaryotes, SUMO and SUMO system are still unknown in some eukaryotic unicellular organisms, such as Trypanosoma brucei (T. brucei). In this study, only one SUMO homologue (TbSUMO) was identified in T. brucei. Expression of TbSUMO was knocked down by using RNA interference technique in procyclic-form T. brucei. The growth of TbSUMO-deficient cells was significantly inhibited. TbSUMO-deficient cells were arrested in G2/M phase accompanied with an obvious increase of 0N1K cells (zoids), and failed in chromosome segregation. These results indicate that TbSUMO is essential in cell cycle regulation, with one important role in mitosis. Meanwhile, the enrichment of zoids suggests the inhibition of mitosis does not prevent the cell division in procyclic-form T. brucei. HA-tagged TbSUMO was overexpressed in T. brucei and was shown to be localized to the nucleus through the whole cell cycle, further revealing its distinguished functions in nucleus. All these accumulated data imply that a SUMO system essential for regulating cell cycle progression might exist in the procyclic-form T. brucei.
Collapse
Affiliation(s)
- Shanhui Liao
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230026, PR China
| | | | | | | |
Collapse
|
26
|
Srilunchang KO, Krohn NG, Dresselhaus T. DiSUMO-like DSUL is required for nuclei positioning, cell specification and viability during female gametophyte maturation in maize. Development 2010; 137:333-45. [PMID: 20040499 DOI: 10.1242/dev.035964] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Reversible post-translational modification of numerous proteins by small ubiquitin-related modifiers (SUMOs) represents a major regulatory process in various eukaryotic cellular and developmental processes. To study the role of sumoylation during female gametophyte (FG) development in maize, we identified Zea mays genes encoding SUMO (ZmSUMO1a and ZmSUMO1b) and a diSUMO-like protein called ZmDSUL that contains two head-to-tail SUMO-like domains. Whereas ZmSUMO1a and ZmSUMO1b are almost ubiquitously expressed, ZmDSUL transcripts were detected exclusively in the egg apparatus and zygote. ZmDSUL was selected for detailed studies. ZmDSUL is processed close to the C-terminus, generating a dimeric protein that is similar to animal FAT10 and ISG15, which contain two ubiquitin-like domains. Whereas GFP fused to the ZmDSUL N-terminus was located in the cytoplasm and predominately in the nucleoplasm of some transiently transformed maize suspension cells, C-terminal GFP fusions exclusively accumulated at the nuclear surface. GFP or ZmDSUL-GFP under control of the ZmDSUL promoter first displayed GFP signals in the micropylar-most position of the FG at stage 5/6, when migration of polar nuclei and cellularization occurs. Mature FGs displayed GFP signals exclusively in the egg cell, but the strongest signals were observed shortly after fertilization and disappeared during the first asymmetric zygotic division. RNAi silencing of ZmDSUL showed that it is required for FG viability. Moreover, nuclei segregation and positioning defects occurred at stage FG 5 after mitotic nuclear divisions were completed. In summary, we report a diSUMO-like protein that appears to be essential for nuclei segregation and positioning, the prerequisite for cell specification during FG maturation.
Collapse
Affiliation(s)
- Kanok-orn Srilunchang
- Cell Biology and Plant Biochemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | | | | |
Collapse
|
27
|
Spirek M, Estreicher A, Csaszar E, Wells J, McFarlane RJ, Watts FZ, Loidl J. SUMOylation is required for normal development of linear elements and wild-type meiotic recombination in Schizosaccharomyces pombe. Chromosoma 2009; 119:59-72. [PMID: 19756689 DOI: 10.1007/s00412-009-0241-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 07/24/2009] [Accepted: 07/27/2009] [Indexed: 01/20/2023]
Abstract
In the fission yeast, Schizosaccharomyces pombe, synaptonemal complexes (SCs) are not formed during meiotic prophase. However, structures resembling the axial elements of SCs, the so-called linear elements (LinEs) appear. By in situ immunostaining, we found Pmt3 (S. pombe's SUMO protein) transiently along LinEs, suggesting that SUMOylation of some component(s) of LinEs occurs during meiosis. Mutation of the SUMO ligase Pli1 caused aberrant LinE formation and reduced genetic recombination indicating a role for SUMOylation of LinEs for the regulation of meiotic recombination. Western blot analysis of TAP-tagged Rec10 demonstrated that there is a Pli1-dependent posttranslational modification of this protein, which is a major LinE component and a distant homolog of the SC protein Red1. Mass spectrometry (MS) analysis revealed that Rec10 is both phosphorylated and ubiquitylated, but no evidence for SUMOylation of Rec10 was found. These findings indicate that the regulation of LinE and Rec10 function is modulated by Pli1-dependent SUMOylation of LinE protein(s) which directly or indirectly regulates Rec10 modification. On the side, MS analysis confirmed the interaction of Rec10 with the known LinE components Rec25, Rec27, and Hop1 and identified the meiotically upregulated protein Mug20 as a novel putative LinE-associated protein.
Collapse
Affiliation(s)
- Mario Spirek
- Department of Chromosome Biology, Center for Molecular Biology of the University of Vienna (MFPL), Dr. Bohr Gasse 1, 1030, Vienna, Austria
| | | | | | | | | | | | | |
Collapse
|
28
|
Skilton A, Ho JCY, Mercer B, Outwin E, Watts FZ. SUMO chain formation is required for response to replication arrest in S. pombe. PLoS One 2009; 4:e6750. [PMID: 19707600 PMCID: PMC2727700 DOI: 10.1371/journal.pone.0006750] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2009] [Accepted: 07/15/2009] [Indexed: 11/28/2022] Open
Abstract
SUMO is a ubiquitin-like protein that is post-translationally attached to one or more lysine residues on target proteins. Despite having only 18% sequence identity with ubiquitin, SUMO contains the conserved ββαββαβ fold present in ubiquitin. However, SUMO differs from ubiquitin in having an extended N-terminus. In S. pombe the N-terminus of SUMO/Pmt3 is significantly longer than those of SUMO in S. cerevisiae, human and Drosophila. Here we investigate the role of this N-terminal region. We have used two dimensional gel electrophoresis to demonstrate that S. pombe SUMO/Pmt3 is phosphorylated, and that this occurs on serine residues at the extreme N-terminus of the protein. Mutation of these residues (in pmt3-1) results in a dramatic reduction in both the levels of high Mr SUMO-containing species and of total SUMO/Pmt3, indicating that phosphorylation of SUMO/Pmt3 is required for its stability. Despite the significant reduction in high Mr SUMO-containing species, pmt3-1 cells do not display an aberrant cell morphology or sensitivity to genotoxins or stress. Additionally, we demonstrate that two lysine residues in the N-terminus of S. pombe SUMO/Pmt3 (K14 and K30) can act as acceptor sites for SUMO chain formation in vitro. Inability to form SUMO chains results in aberrant cell and nuclear morphologies, including stretched and fragmented chromatin. SUMO chain mutants are sensitive to the DNA synthesis inhibitor, hydroxyurea (HU), but not to other genotoxins, such as UV, MMS or CPT. This implies a role for SUMO chains in the response to replication arrest in S. pombe.
Collapse
Affiliation(s)
- Andrew Skilton
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, United Kingdom
| | - Jenny C. Y. Ho
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, United Kingdom
| | - Brenda Mercer
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, United Kingdom
| | - Emily Outwin
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, United Kingdom
| | - Felicity Z. Watts
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, United Kingdom
- * E-mail:
| |
Collapse
|
29
|
Abstract
Centrins are multifunctional Ca(2+)-binding proteins that are highly conserved from yeast to humans. Centrin-2 is a core component of the centrosome of higher eukaryotes. In addition, it is present within the nucleus, in which it is part of the xeroderma pigmentosum group C (XPC) complex, which controls nucleotide excision repair (NER). Regulation of the subcellular distribution of centrin-2 has so far remained elusive. Here we show that centrin-2 is a substrate of SUMOylation in vitro and in vivo, and that it is preferentially modified by SUMO2/3. Moreover, we identify the SUMO E3-like ligase human polycomb protein 2 (PC2; also known as hPC2) as essential for centrin-2 modification. Interference with the SUMOylation pathway leads to a striking defect in nuclear localization of centrin-2 and accumulation in the cytoplasm, whereas centrosomal recruitment of centrin-2 is unaffected. Depletion of the XPC protein mimics this situation and we provide evidence that SUMO conjugation of centrin-2 enhances its binding to the XPC protein. These data show that the nucleocytoplasmic shuttling of centrin-2 depends on the SUMO system and indicates that localization of centrin-2 within the nucleus depends on its ability to bind to the XPC protein.
Collapse
Affiliation(s)
- Ulf R Klein
- Department of Cell Biology, Max-Planck Institute of Biochemistry, D-82152 Martinsried, Germany.
| | | |
Collapse
|
30
|
Kim KI, Baek SH. Small ubiquitin-like modifiers in cellular malignancy and metastasis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 273:265-311. [PMID: 19215907 DOI: 10.1016/s1937-6448(08)01807-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Small ubiquitin-like modifiers (SUMOs) mediate a variety of cellular functions of protein targets mainly in the nucleus but in other cellular compartments as well, and thereby participate in maintaining cellular homeostasis. SUMO system plays important roles in transcriptional regulation, DNA damage responses, maintaining genome integrity, and signaling pathways. Thus, in some cases, loss of regulated control on SUMOylation/deSUMOylation processes causes a defect in maintaining homeostasis and hence gives a cue to cancer development and progression. Furthermore, recent studies have revealed that SUMO system is involved in cancer metastasis. In this review, we will summarize the possible role of SUMO system in cancer development, progression, and metastasis and discuss future directions.
Collapse
Affiliation(s)
- Keun Il Kim
- Department of Biological Sciences, Research Center for Women's Disease, Sookmyung Women's University, Seoul, Korea
| | | |
Collapse
|
31
|
Abstract
Post-translational modification by SUMO is now recognized as an important regulatory method employed by the cell to reversibly modulate the activity, stability, or localization of intracellular proteins. A dedicated enzymatic machinery is involved in the processing, attachment, and removal of the modifier with high selectivity. SUMO modification generally alters the properties of the modified target by influencing-either positively or negatively-its interactions with other cellular factors. As a consequence, the SUMO system contributes to the regulation of numerous biological pathways, ranging from nucleocytoplasmic transport to the repression of transcriptional activity and the maintenance of genome stability by its influence on DNA recombination and repair. This chapter gives a brief overview over the enzymes of the SUMO system, its regulation, and its functions.
Collapse
Affiliation(s)
- Helle D Ulrich
- Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms, UK
| |
Collapse
|
32
|
Klein UR, Haindl M, Nigg EA, Muller S. RanBP2 and SENP3 function in a mitotic SUMO2/3 conjugation-deconjugation cycle on Borealin. Mol Biol Cell 2008; 20:410-8. [PMID: 18946085 DOI: 10.1091/mbc.e08-05-0511] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The ubiquitin-like SUMO system controls cellular key functions, and several lines of evidence point to a critical role of SUMO for mitotic progression. However, in mammalian cells mitotic substrates of sumoylation and the regulatory components involved are not well defined. Here, we identify Borealin, a component of the chromosomal passenger complex (CPC), as a mitotic target of SUMO. The CPC, which additionally comprises INCENP, Survivin, and Aurora B, regulates key mitotic events, including chromosome congression, the spindle assembly checkpoint, and cytokinesis. We show that Borealin is preferentially modified by SUMO2/3 and demonstrate that the modification is dynamically regulated during mitotic progression, peaking in early mitosis. Intriguingly, the SUMO ligase RanBP2 interacts with the CPC, stimulates SUMO modification of Borealin in vitro, and is required for its modification in vivo. Moreover, the SUMO isopeptidase SENP3 is a specific interaction partner of Borealin and catalyzes the removal of SUMO2/3 from Borealin. These data thus delineate a mitotic SUMO2/3 conjugation-deconjugation cycle of Borealin and further assign a regulatory function of RanBP2 and SENP3 in the mitotic SUMO pathway.
Collapse
Affiliation(s)
- Ulf R Klein
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | | | | | | |
Collapse
|
33
|
Developmental control of sumoylation pathway proteins in mouse male germ cells. Dev Biol 2008; 321:227-37. [PMID: 18602382 DOI: 10.1016/j.ydbio.2008.06.020] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 05/15/2008] [Accepted: 06/12/2008] [Indexed: 01/15/2023]
Abstract
Protein sumoylation regulates a variety of nuclear functions and has been postulated to be involved in meiotic chromosome dynamics as well as other processes of spermatogenesis. Here, the expression and distribution of sumoylation pathway genes and proteins were determined in mouse male germ cells, with a particular emphasis on prophase I of meiosis. Immunofluorescence microscopy revealed that SUMO1, SUMO2/3 and UBE2I (also known as UBC9) were localized to the XY body in pachytene and diplotene spermatocytes, while only SUMO2/3 and UBE2I were detected near centromeres in metaphase I spermatocytes. Quantitative RT-PCR and Western blotting were used to examine the expression of sumoylation pathway genes and proteins in enriched preparations of leptotene/zygotene spermatocytes, prepubertal and adult pachytene spermatocytes, as well as round spermatids. Two general expression profiles emerged from these data. The first profile, where expression was more prominent during meiosis, identified sumoylation pathway participants that could be involved in meiotic chromosome dynamics. The second profile, elevated expression in post-meiotic spermatids, suggested proteins that could be involved in spermiogenesis-related sumoylation events. In addition to revealing differential expression of protein sumoylation mediators, which suggests differential functioning, these data demonstrate the dynamic nature of SUMO metabolism during spermatogenesis.
Collapse
|
34
|
SUMO-2/3 modification and binding regulate the association of CENP-E with kinetochores and progression through mitosis. Mol Cell 2008; 29:729-41. [PMID: 18374647 DOI: 10.1016/j.molcel.2008.01.013] [Citation(s) in RCA: 194] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Revised: 11/15/2007] [Accepted: 01/07/2008] [Indexed: 12/31/2022]
Abstract
SUMOylation is essential for cell-cycle regulation in invertebrates; however, its functions during the mammalian cell cycle are largely uncharacterized. Mammals express three SUMO paralogs: SUMO-1, SUMO-2, and SUMO-3 (SUMO-2 and SUMO-3 are 96% identical and referred to as SUMO-2/3). We found that SUMO-2/3 localize to centromeres and condensed chromosomes, whereas SUMO-1 localizes to the mitotic spindle and spindle midzone, indicating that SUMO paralogs regulate distinct mitotic processes in mammalian cells. Consistent with this, global inhibition of SUMOylation caused a prometaphase arrest due to defects in targeting the microtubule motor protein CENP-E to kinetochores. CENP-E was found to be modified specifically by SUMO-2/3 and to possess SUMO-2/3 polymeric chain-binding activity essential for kinetochore localization. Our findings indicate that SUMOylation is a key regulator of the mammalian cell cycle, with SUMO-1 and SUMO-2/3 modification of different proteins regulating distinct processes.
Collapse
|
35
|
Agostinho M, Santos V, Ferreira F, Costa R, Cardoso J, Pinheiro I, Rino J, Jaffray E, Hay RT, Ferreira J. Conjugation of human topoisomerase 2 alpha with small ubiquitin-like modifiers 2/3 in response to topoisomerase inhibitors: cell cycle stage and chromosome domain specificity. Cancer Res 2008; 68:2409-18. [PMID: 18381449 DOI: 10.1158/0008-5472.can-07-2092] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Type 2 topoisomerases, in particular the alpha isoform in human cells, play a key role in cohesion and sister chromatid separation during mitosis. These enzymes are thus vital for cycling cells and are obvious targets in cancer chemotherapy. Evidence obtained in yeast and Xenopus model systems indicates that conjugation of topoisomerase 2 with small ubiquitin-like modifier (SUMO) proteins is required for its mitotic functions. Here, we provide biochemical and cytologic evidence that topoisomerase 2 alpha is conjugated to SUMO-2/3 during interphase and mitosis in response to topoisomerase 2 inhibitors and "poisons" (ICRF-187, etoposide, doxorubicin) that stabilize catalytic intermediates (cleavage complexes, closed clamp forms) of the enzyme onto target DNA. During mitosis, SUMO-2/3-modified forms of topoisomerase 2 alpha localize to centromeres and chromosome cores/axes. However, centromeres are unresponsive to inhibitors during interphase. Furthermore, formation of topoisomerase 2 alpha-SUMO-2/3 conjugates within mitotic chromosomes strongly correlates with incomplete chromatid decatenation and decreases progressively as cells approach the metaphase-anaphase transition. We also found that the PIASy protein, an E3 ligase for SUMO proteins, colocalizes with SUMO-2/3 at the mitotic chromosomal cores/axes and is necessary for both formation of SUMO-2/3 conjugates and proper chromatid segregation. We suggest that the efficacy of topoisomerase inhibitors to arrest cells traversing mitosis may relate to their targeting of topoisomerase 2 alpha-SUMO-2/3 conjugates that concentrate at mitotic chromosome axes and are directly involved in chromatid arm separation.
Collapse
Affiliation(s)
- Marta Agostinho
- Instituto de Medicina Molecular, Faculdade de Medicina, Lisboa, Portugal
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
A SIM-ultaneous role for SUMO and ubiquitin. Trends Biochem Sci 2008; 33:201-8. [PMID: 18403209 DOI: 10.1016/j.tibs.2008.02.001] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 02/08/2008] [Accepted: 02/12/2008] [Indexed: 11/22/2022]
Abstract
Ubiquitin and ubiquitin-like proteins (Ubls) share a beta-GRASP fold and have key roles in cellular growth and suppression of genome instability. Despite their common fold, SUMO and ubiquitin are classically portrayed as distinct, and they can have antagonistic roles. Recently, a new family of proteins, the small ubiquitin-related modifier (SUMO)-targeted ubiquitin ligases (STUbLs), which directly connect sumoylation and ubiquitylation, has been discovered. Uniquely, STUbLs use SUMO-interaction motifs (SIMs) to recognize their sumoylated targets. STUbLs are global regulators of protein sumoylation levels, and cells lacking STUbLs display genomic instability and hypersensitivity to genotoxic stress. The human STUbL, RNF4, is implicated in several diseases including cancer, highlighting the importance of characterizing the cellular functions of STUbLs.
Collapse
|
37
|
Abstract
Attachment of the SUMO (small ubiquitin-related modifier) to the replication factor PCNA (proliferating-cell nuclear antigen) in the budding yeast has been shown to recruit a helicase, Srs2, to active replication forks, which in turn prevents unscheduled recombination events. In the present review, I will discuss how the interaction between SUMOylated PCNA and Srs2 serves as an example for a mechanism by which SUMO modulates the properties of its targets and mediates the activation of downstream effector proteins.
Collapse
|
38
|
Abstract
In the eukaryotic nucleus, gene expression and maintenance of genome integrity are tightly controlled at multiple levels, from the molecular details to the higher-order structure of the genome. The nucleus contains spatially and functionally distinct compartments in which these fundamental processes are carried out. While the dynamics and functions of some nuclear subdomains, like the nucleolus, have been well studied, other domains, like the PML-nuclear bodies, remain enigmatic. Recent evidence has now implicated the SUMOylation pathway as an important player in subnuclear architecture, particularly in the assembly of PML-nuclear bodies. Related functions include the organization of chromatin loops and maintenance of rDNA repeat stability. Consequently, complete loss of SUMO modification profoundly affects nuclear organization and cell viability.
Collapse
Affiliation(s)
- Patrick Heun
- Max Planck Institute of Immunobiology, Stübeweg 51, Freiburg 79108, Germany.
| |
Collapse
|
39
|
Current awareness on yeast. Yeast 2007. [DOI: 10.1002/yea.1452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|