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Delisle SV, Labreche C, Lara-Márquez M, Abou-Hamad J, Garland B, Lamarche-Vane N, Sabourin LA. Expression of a kinase inactive SLK is embryonic lethal and impairs cell migration in fibroblasts. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119783. [PMID: 38871226 DOI: 10.1016/j.bbamcr.2024.119783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 06/03/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024]
Abstract
Kinases are known to have kinase activity independent functions. To gain further insights into potential kinase-independent functions of SLK/STK2, we have developed a kinase-dead allele, SLKK63R using in vivo CRISPR/Cas technology. Our studies show that blastocysts homozygote for SLKK63R do not develop into viable mice. However, heterozygotes are viable and fertile with no overt phenotypes. Analyses of mouse embryonic fibroblasts show that expression of SLKK63R results in a 50% decrease in kinase activity in heterozygotes. In contrast to previous studies, our data show that SLK does not form homodimers and that the kinase defective allele does not act in a dominant negative fashion. Expression of SLKK63R leads to altered Rac1 and RhoA activity, increased stress fiber formation and delayed focal adhesion turnover. Our data support a previously observed role for SLK in cell migration and suggest that at least 50% kinase activity is sufficient for embryonic development.
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Affiliation(s)
- Samuel V Delisle
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Cedrik Labreche
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Mónica Lara-Márquez
- Cancer Research Program, Research Institute of the McGill University Health Centre and Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - John Abou-Hamad
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Dept. of Cancer Therapeutics, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Brennan Garland
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Nathalie Lamarche-Vane
- Cancer Research Program, Research Institute of the McGill University Health Centre and Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Luc A Sabourin
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Dept. of Cancer Therapeutics, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
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2
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Tao M, Li Z, Liu M, Ma H, Liu W. Association analysis of polymorphisms in SLK, ARHGEF9, WWC2, GAB3, and FSHR genes with reproductive traits in different sheep breeds. Front Genet 2024; 15:1371872. [PMID: 38680425 PMCID: PMC11045898 DOI: 10.3389/fgene.2024.1371872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/01/2024] [Indexed: 05/01/2024] Open
Abstract
The aim was to investigate the relationship between polymorphisms of gene mutation loci and reproductive traits in local sheep breeds (Duolang Sheep) and introduced sheep breeds (Suffolk, Hu Sheep) in Xinjiang to provide new molecular markers for the selection and breeding of high fecundity sheep. The expression pattern of typing successful genes in sheep tissues was investigated by RT-qPCR technology, providing primary data for subsequent verification of gene function. The 26 mutation loci of WWC2, ARHGEF9, SLK, GAB3, and FSHR genes were typed using KASP. Association analyses were performed using SPSS 25.0, and the typing results showed that five genes with six loci, WWC2 (g.14962207 C>T), ARHGEF9 (g.48271079 C>A), SLK (g.27107842 T>C, g.27108855 G>A), GAB3 (g.86134602 G>A), and FSHR (g.80789180 T>G) were successfully typed. The results of the association analyses showed that WWC2 (g.14962207 C>T), SLK (g.27108855 G>A), ARHGEF9 (g.48271079 C>A), and FSHR (g.80789180 T>G) caused significant or extremely significant effects on the litter size in Duolang, Suffolk and Hu Sheep populations. The expression distribution pattern of the five genes in 12 sheep reproduction-related tissues was examined by RT-qPCR. The results showed that the expression of the SLK gene in the uterus, the FSHR gene in the ovary, and the ARHGEF9 gene in hypothalamic-pituitary-gonadal axis-related tissues were significantly higher than in the tissues of other parts of the sheep. WWC2 and GAB3 genes were highly expressed both in reproductive organs and visceral tissues. In summary, the WWC2 (g.14962207 C>T), SLK (g.27108855 G>A), ARHGEF9 (g.48271079 C>A), and FSHR (g.80789180 T>G) loci can be used as potential molecular markers for detecting differences in reproductive performance in sheep. Due to variations in typing results, the SLK (g.27107842 T>C) and GAB3 (g.86134602 G>A) loci need further validation.
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Affiliation(s)
- Meini Tao
- College of Animal Science, Xinjiang Agricultural University, Urumqi, China
- Adsen Biotechnology Co., Ltd., Urumchi, China
| | - Zhiqiang Li
- Adsen Biotechnology Co., Ltd., Urumchi, China
| | - Meng Liu
- College of Animal Science, Xinjiang Agricultural University, Urumqi, China
| | - Haiyu Ma
- College of Animal Science, Xinjiang Agricultural University, Urumqi, China
| | - Wujun Liu
- College of Animal Science, Xinjiang Agricultural University, Urumqi, China
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3
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Zeng X, Jiang S, Zhong Z, Yang X, Chen Q, Li J, Zhu Z, Song J, Yang C. DIRECT: Digital Microfluidics for Isolation-Free Shared Library Construction of Single-Cell DNA Methylome and Transcriptome. SMALL METHODS 2024; 8:e2301075. [PMID: 37772685 DOI: 10.1002/smtd.202301075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/04/2023] [Indexed: 09/30/2023]
Abstract
Simultaneous profiling of DNA methylation and gene expression within single cells is a powerful technology to dissect complex gene regulatory network of cells. However, existing methods are based on picking a single-cell in a tube and split single-cell lysate into two parts for transcriptome and methylome library construction, respectively, which is costly and cumbersome. Here, DIRECT is proposed, a digital microfluidics-based method for high-efficiency single-cell isolation and simultaneous analysis of the methylome and transcriptome in a single library construction. The accuracy of DIRECT is demonstrated in comparison with bulk and single-omics data, and the high CpG site coverage of DIRECT allows for precise analysis of copy number variation information, enabling expansion of single cell analysis from two- to three-omics. By applying DIRECT to monitor the dynamics of mouse embryonic stem cell differentiation, the relationship between DNA methylation and changes in gene expression during differentiation is revealed. DIRECT enables accurate, robust, and reproducible single-cell DNA methylation and gene expression co-analysis in a more cost-effective, simpler library preparation and automated manner, broadening the application scenarios of single-cell multi-omics analysis and revealing a more comprehensive and fine-grained map of cellular regulatory landscapes.
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Affiliation(s)
- Xi Zeng
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Shaowei Jiang
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Zhixing Zhong
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Xiaoping Yang
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Qiuyue Chen
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Jin Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, 200433, P. R. China
| | - Zhi Zhu
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Jia Song
- Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200120, P. R. China
| | - Chaoyong Yang
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
- Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200120, P. R. China
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4
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Dou Y, Liu Y, Yi X, Olsen LK, Zhu H, Gao Q, Zhou H, Zhang B. SEPepQuant enhances the detection of possible isoform regulations in shotgun proteomics. Nat Commun 2023; 14:5809. [PMID: 37726316 PMCID: PMC10509223 DOI: 10.1038/s41467-023-41558-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 09/06/2023] [Indexed: 09/21/2023] Open
Abstract
Shotgun proteomics is essential for protein identification and quantification in biomedical research, but protein isoform characterization is challenging due to the extensive number of peptides shared across proteins, hindering our understanding of protein isoform regulation and their roles in normal and disease biology. We systematically assess the challenge and opportunities of shotgun proteomics-based protein isoform characterization using in silico and experimental data, and then present SEPepQuant, a graph theory-based approach to maximize isoform characterization. Using published data from one induced pluripotent stem cell study and two human hepatocellular carcinoma studies, we demonstrate the ability of SEPepQuant in addressing the key limitations of existing methods, providing more comprehensive isoform-level characterization, identifying hundreds of isoform-level regulation events, and facilitating streamlined cross-study comparisons. Our analysis provides solid evidence to support a widespread role of protein isoform regulation in normal and disease processes, and SEPepQuant has broad applications to biological and translational research.
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Affiliation(s)
- Yongchao Dou
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Yuejia Liu
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, 210023, Nanjing, Jiangsu, China
| | - Xinpei Yi
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Lindsey K Olsen
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Hongwen Zhu
- Department of Analytical Chemistry, State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, 201203, Shanghai, China
| | - Qiang Gao
- Department of Liver Surgery and Transplantation, Liver Cancer Institute, Zhongshan Hospital, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education, 180 Fenglin Road, 200032, Shanghai, China
| | - Hu Zhou
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, 210023, Nanjing, Jiangsu, China
- Department of Analytical Chemistry, State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, 201203, Shanghai, China
| | - Bing Zhang
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, 77030, USA.
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
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5
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Song K, Jiang X, Xu X, Chen Y, Zhang J, Tian Y, Wang Q, Weng J, Liang Y, Ma W. Ste20-like kinase activity promotes meiotic resumption and spindle microtubule stability in mouse oocytes. Cell Prolif 2022; 56:e13391. [PMID: 36579845 PMCID: PMC10068952 DOI: 10.1111/cpr.13391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/30/2022] Open
Abstract
Ste20-like kinase (SLK) is involved in cell proliferation and migration in somatic cells. This study aims to explore SLK expression and function in mouse oocyte meiosis. Western blot, immunofluorescence, Co-immunoprecipitation, drug treatment, cRNA construct and in vitro transcription, microinjection of morpholino oilgo (MO) and cRNA were performed in oocytes. High and stable protein expression of SLK was detected in mouse oocyte meiosis, with dynamic distribution in the nucleus, chromosomes and spindle apparatus. SLK phosphorylation emerges around meiotic resumption and reaches a peak during metaphase I (MI) and metaphase II. SLK knockdown with MO or expression of kinase-dead SLK K63R dramatically delays meiotic resumption due to sequentially suppressed phosphorylation of Polo-like kinase 1 (Plk1) and cell division cycle 25C (CDC25C) and dephosphorylation of cyclin-dependent kinase 1 (CDK1). SLK depletion promotes ubiquitination-mediated degradation of paxillin, an antagonist to α-tubulin deacetylation, and thus destroys spindle assembly and chromosome alignment; these phenotypes can be substantially rescued by exogenous expression of SLK kinase active fragment. Additionally, exogenous SLK effectively promotes meiotic progression and spindle assembly in aging oocytes with reduced SLK. Collectively, this study reveals SLK is required for meiotic resumption and spindle assembly in mouse oocyte meiosis.
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Affiliation(s)
- Ke Song
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Xiuying Jiang
- Division of Sport Anatomy, School of Sport Science, Beijing Sport University, Beijing, China
| | - Xiangning Xu
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Ye Chen
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Jiaqi Zhang
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Ying Tian
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Qian Wang
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Jing Weng
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yuanjing Liang
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Wei Ma
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
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6
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Ste20-like Kinase Is Critical for Inhibitory Synapse Maintenance and Its Deficiency Confers a Developmental Dendritopathy. J Neurosci 2021; 41:8111-8125. [PMID: 34400520 DOI: 10.1523/jneurosci.0352-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/18/2021] [Accepted: 05/29/2021] [Indexed: 11/21/2022] Open
Abstract
The size and structure of the dendritic arbor play important roles in determining how synaptic inputs of neurons are converted to action potential output. The regulatory mechanisms governing the development of dendrites, however, are insufficiently understood. The evolutionary conserved Ste20/Hippo kinase pathway has been proposed to play an important role in regulating the formation and maintenance of dendritic architecture. A key element of this pathway, Ste20-like kinase (SLK), regulates cytoskeletal dynamics in non-neuronal cells and is strongly expressed throughout neuronal development. However, its function in neurons is unknown. We show that, during development of mouse cortical neurons, SLK has a surprisingly specific role for proper elaboration of higher, ≥ third-order dendrites both in male and in female mice. Moreover, we demonstrate that SLK is required to maintain excitation-inhibition balance. Specifically, SLK knockdown caused a selective loss of inhibitory synapses and functional inhibition after postnatal day 15, whereas excitatory neurotransmission was unaffected. Finally, we show that this mechanism may be relevant for human disease, as dysmorphic neurons within human cortical malformations revealed significant loss of SLK expression. Overall, the present data identify SLK as a key regulator of both dendritic complexity during development and inhibitory synapse maintenance.SIGNIFICANCE STATEMENT We show that dysmorphic neurons of human epileptogenic brain lesions have decreased levels of the Ste20-like kinase (SLK). Decreasing SLK expression in mouse neurons revealed that SLK has essential functions in forming the neuronal dendritic tree and in maintaining inhibitory connections with neighboring neurons.
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7
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Serafim RAM, Sorrell FJ, Berger BT, Collins RJ, Vasconcelos SNS, Massirer KB, Knapp S, Bennett J, Fedorov O, Patel H, Zuercher WJ, Elkins JM. Discovery of a Potent Dual SLK/STK10 Inhibitor Based on a Maleimide Scaffold. J Med Chem 2021; 64:13259-13278. [PMID: 34463505 DOI: 10.1021/acs.jmedchem.0c01579] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
SLK (STE20-like kinase) and STK10 (serine/threonine kinase 10) are closely related kinases whose enzymatic activity is linked to the regulation of ezrin, radixin, and moesin function and to the regulation of lymphocyte migration and the cell cycle. We identified a series of 3-anilino-4-arylmaleimides as dual inhibitors of SLK and STK10 with good kinome-wide selectivity. Optimization of this series led to multiple SLK/STK10 inhibitors with nanomolar potency. Crystal structures of exemplar inhibitors bound to SLK and STK10 demonstrated the binding mode of the inhibitors and rationalized their selectivity. Cellular target engagement assays demonstrated the binding of the inhibitors to SLK and STK10 in cells. Further selectivity analyses, including analysis of activity of the reported inhibitors against off-targets in cells, identified compound 31 as the most potent and selective inhibitor of SLK and STK10 yet reported.
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Affiliation(s)
- Ricardo A M Serafim
- Center for Medicinal Chemistry (CQMED), Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP 13083-875, Brazil.,Structural Genomics Consortium, University of Campinas (UNICAMP), Av. Dr. André Tosello, 550, Barão Geraldo, Campinas, SP 13083-886, Brazil
| | - Fiona J Sorrell
- Centre for Medicines Discovery, University of Oxford, Old Road Campus Research Building, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, U.K
| | - Benedict-Tilman Berger
- Structural Genomics Consortium, Johann Wolfgang Goethe University, Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Str. 15, D-60438 Frankfurt am Main, DE, Germany.,Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, DE, Germany
| | - Ross J Collins
- Medicines Discovery Institute, School of Biosciences, Cardiff University, Cardiff CF10 3AT, U.K
| | - Stanley N S Vasconcelos
- Center for Medicinal Chemistry (CQMED), Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP 13083-875, Brazil.,Structural Genomics Consortium, University of Campinas (UNICAMP), Av. Dr. André Tosello, 550, Barão Geraldo, Campinas, SP 13083-886, Brazil
| | - Katlin B Massirer
- Center for Medicinal Chemistry (CQMED), Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, SP 13083-875, Brazil.,Structural Genomics Consortium, University of Campinas (UNICAMP), Av. Dr. André Tosello, 550, Barão Geraldo, Campinas, SP 13083-886, Brazil
| | - Stefan Knapp
- Structural Genomics Consortium, Johann Wolfgang Goethe University, Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Str. 15, D-60438 Frankfurt am Main, DE, Germany.,Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe University, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, DE, Germany
| | - James Bennett
- Centre for Medicines Discovery, University of Oxford, Old Road Campus Research Building, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, U.K
| | - Oleg Fedorov
- Centre for Medicines Discovery, University of Oxford, Old Road Campus Research Building, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, U.K
| | - Hitesh Patel
- Medicines Discovery Institute, School of Biosciences, Cardiff University, Cardiff CF10 3AT, U.K
| | - William J Zuercher
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jonathan M Elkins
- Structural Genomics Consortium, University of Campinas (UNICAMP), Av. Dr. André Tosello, 550, Barão Geraldo, Campinas, SP 13083-886, Brazil.,Centre for Medicines Discovery, University of Oxford, Old Road Campus Research Building, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, U.K
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8
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Garland B, Delisle S, Al-Zahrani KN, Pryce BR, Sabourin LA. The Ste20-like kinase - a Jack of all trades? J Cell Sci 2021; 134:261804. [PMID: 33961052 DOI: 10.1242/jcs.258269] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Over the past 20 years, the Ste20-like kinase (SLK; also known as STK2) has emerged as a central regulator of cytoskeletal dynamics. Reorganization of the cytoskeleton is necessary for a plethora of biological processes including apoptosis, proliferation, migration, tissue repair and signaling. Several studies have also uncovered a role for SLK in disease progression and cancer. Here, we review the recent findings in the SLK field and summarize the various roles of SLK in different animal models and discuss the biochemical mechanisms regulating SLK activity. Together, these studies have revealed multiple roles for SLK in coupling cytoskeletal dynamics to cell growth, in muscle repair and in negative-feedback loops critical for cancer progression. Furthermore, the ability of SLK to regulate some systems appears to be kinase activity independent, suggesting that it may be an important scaffold for signal transduction pathways. These various findings reveal highly complex functions and regulation patterns of SLK in development and disease, making it a potential therapeutic target.
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Affiliation(s)
- Brennan Garland
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Samuel Delisle
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Khalid N Al-Zahrani
- Center for Molecular and Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G1X5, Canada
| | - Benjamin R Pryce
- Department of Pediatrics, Hollings Cancer Center, Medical University of South Carolina,Charleston, SC 29425, USA
| | - Luc A Sabourin
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
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9
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Wang Y, Wang R, Tang DD. Ste20-like Kinase-mediated Control of Actin Polymerization Is a New Mechanism for Thin Filament-associated Regulation of Airway Smooth Muscle Contraction. Am J Respir Cell Mol Biol 2020; 62:645-656. [PMID: 31913659 PMCID: PMC7193783 DOI: 10.1165/rcmb.2019-0310oc] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/07/2020] [Indexed: 12/26/2022] Open
Abstract
It has been reported that actin polymerization is regulated by protein tyrosine phosphorylation in smooth muscle on contractile stimulation. The role of protein serine/threonine phosphorylation in modulating actin dynamics is underinvestigated. SLK (Ste20-like kinase) is a serine/threonine protein kinase that plays a role in apoptosis, cell cycle, proliferation, and migration. The function of SLK in smooth muscle is mostly unknown. Here, SLK knockdown (KD) inhibited acetylcholine (ACh)-induced actin polymerization and contraction without affecting myosin light chain phosphorylation at Ser-19 in human airway smooth muscle. Stimulation with ACh induced paxillin phosphorylation at Ser-272, which was reduced in SLK KD cells. However, SLK did not catalyze paxillin Ser-272 phosphorylation in vitro. But, SLK KD attenuated Plk1 (polo-like kinase 1) phosphorylation at Thr-210. Plk1 mediated paxillin phosphorylation at Ser-272 in vitro. Expression of the nonphosphorylatable paxillin mutant S272A (substitution of alanine at Ser-272) attenuated the agonist-enhanced F-actin/G-actin ratios without affecting myosin light chain phosphorylation. Because N-WASP (neuronal Wiskott-Aldrich Syndrome Protein) phosphorylation at Tyr-256 (an indication of its activation) promotes actin polymerization, we also assessed the role of paxillin phosphorylation in N-WASP activation. S272A paxillin inhibited the ACh-enhanced N-WASP phosphorylation at Tyr-256. Together, these results suggest that SLK regulates paxillin phosphorylation at Ser-272 via Plk1, which modulates N-WASP activation and actin polymerization in smooth muscle. SLK-mediated actin cytoskeletal reorganization may facilitate force transmission between the contractile units and the extracellular matrix.
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Affiliation(s)
- Yinna Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Ruping Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Dale D Tang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
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10
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Cybulsky AV, Papillon J, Guillemette J, Belkina N, Patino-Lopez G, Torban E. Ste20-like kinase, SLK, a novel mediator of podocyte integrity. Am J Physiol Renal Physiol 2017; 315:F186-F198. [PMID: 29187370 DOI: 10.1152/ajprenal.00238.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
SLK is essential for embryonic development and may play a key role in wound healing, tumor growth, and metastasis. Expression and activation of SLK are increased in kidney development and during recovery from ischemic acute kidney injury. Overexpression of SLK in glomerular epithelial cells/podocytes in vivo induces injury and proteinuria. Conversely, reduced SLK expression leads to abnormalities in cell adhesion, spreading, and motility. Tight regulation of SLK expression thus may be critical for normal renal structure and function. We produced podocyte-specific SLK-knockout mice to address the functional role of SLK in podocytes. Mice with podocyte-specific deletion of SLK showed reduced glomerular SLK expression and activity compared with control. Podocyte-specific deletion of SLK resulted in albuminuria at 4-5 mo of age in male mice and 8-9 mo in female mice, which persisted for up to 13 mo. At 11-12 mo, knockout mice showed ultrastructural changes, including focal foot process effacement and microvillous transformation of podocyte plasma membranes. Mean foot process width was approximately twofold greater in knockout mice compared with control. Podocyte number was reduced by 35% in knockout mice compared with control, and expression of nephrin, synaptopodin, and podocalyxin was reduced in knockout mice by 20-30%. In summary, podocyte-specific deletion of SLK leads to albuminuria, loss of podocytes, and morphological evidence of podocyte injury. Thus, SLK is essential to the maintenance of podocyte integrity as mice age.
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Affiliation(s)
- Andrey V Cybulsky
- Department of Medicine, McGill University Health Centre Research Institute, McGill University , Montreal, Quebec , Canada
| | - Joan Papillon
- Department of Medicine, McGill University Health Centre Research Institute, McGill University , Montreal, Quebec , Canada
| | - Julie Guillemette
- Department of Medicine, McGill University Health Centre Research Institute, McGill University , Montreal, Quebec , Canada
| | - Natalya Belkina
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health , Bethesda, Maryland
| | - Genaro Patino-Lopez
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health , Bethesda, Maryland
| | - Elena Torban
- Department of Medicine, McGill University Health Centre Research Institute, McGill University , Montreal, Quebec , Canada
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11
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Transforming growth factor β-induced epithelial to mesenchymal transition requires the Ste20-like kinase SLK independently of its catalytic activity. Oncotarget 2017; 8:98745-98756. [PMID: 29228724 PMCID: PMC5716764 DOI: 10.18632/oncotarget.21928] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 08/26/2017] [Indexed: 12/27/2022] Open
Abstract
Invasion can be stimulated in vitro using the soluble ligand transforming growth factor-β (TGFβ) to induce a process called epithelial-to-mesenchymal transition (EMT) characterized by cell-cell junction breakdown and an invasive phenotype. We have previously demonstrated a role for Ste20-like kinase SLK cell migration and invasion. Here we show that SLK depletion in NMuMG mammary epithelial cells significantly impairs their TGFβ-induced migration and invasion. Immunofluorescence studies show that a fraction of SLK localizes to E-cadherin-positive adherens junction and that SLK impairs the breakdown of cell-cell contacts. We find that SLK-depleted cultures express significantly lower levels of vimentin protein as well as Snai1 and E-cadherin mRNA levels following TGF-β treatment. Surprisingly, our data show that SLK depletion does not affect the activation and nuclear translocation of Smad3. Furthermore, we show that expression of a dominant negative kinase does not impair tight junction breakdown and rescues Snai1 mRNA expression levels. Together these data suggest that SLK plays a novel role in TGFβ-induced EMT, independent of Smads, in a kinase activity-independent manner.
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12
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Cybulsky AV, Guillemette J, Papillon J, Abouelazm NT. Regulation of Ste20-like kinase, SLK, activity: Dimerization and activation segment phosphorylation. PLoS One 2017; 12:e0177226. [PMID: 28475647 PMCID: PMC5419656 DOI: 10.1371/journal.pone.0177226] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/24/2017] [Indexed: 12/11/2022] Open
Abstract
The Ste20-like kinase, SLK, has diverse cellular functions. SLK mediates organ development, cell cycle progression, cytoskeletal remodeling, cytokinesis, and cell survival. Expression and activity of SLK are enhanced in renal ischemia-reperfusion injury, and overexpression of SLK was shown to induce apoptosis in cultured glomerular epithelial cells (GECs) and renal tubular cells, as well as GEC/podocyte injury in vivo. The SLK protein consists of a N-terminal catalytic domain and an extensive C-terminal domain, which contains coiled-coils. The present study addresses the regulation of SLK activity. Controlled dimerization of the SLK catalytic domain enhanced autophosphorylation of SLK at T183 and S189, which are located in the activation segment. The full-length ectopically- and endogenously-expressed SLK was also autophosphorylated at T183 and S189. Using ezrin as a model SLK substrate (to address exogenous kinase activity), we demonstrate that dimerized SLK 1–373 or full-length SLK can effectively induce activation-specific phosphorylation of ezrin. Mutations in SLK, including T183A, S189A or T193A reduced T183 or S189 autophosphorylation, and showed a greater reduction in ezrin phosphorylation. Mutations in the coiled-coil region of full-length SLK that impair dimerization, in particular I848G, significantly reduced ezrin phosphorylation and tended to reduce autophosphorylation of SLK at T183. In experimental membranous nephropathy in rats, proteinuria and GEC/podocyte injury were associated with increased glomerular SLK activity and ezrin phosphorylation. In conclusion, dimerization via coiled-coils and phosphorylation of T183, S189 and T193 play key roles in the activation and signaling of SLK, and provide targets for novel therapeutic approaches.
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Affiliation(s)
- Andrey V. Cybulsky
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
- * E-mail:
| | - Julie Guillemette
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
| | - Joan Papillon
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
| | - Nihad T. Abouelazm
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
- Department of Clinical Pharmacology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
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13
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Pelaseyed T, Viswanatha R, Sauvanet C, Filter JJ, Goldberg ML, Bretscher A. Ezrin activation by LOK phosphorylation involves a PIP 2-dependent wedge mechanism. eLife 2017; 6. [PMID: 28430576 PMCID: PMC5400502 DOI: 10.7554/elife.22759] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/27/2017] [Indexed: 12/15/2022] Open
Abstract
How cells specify morphologically distinct plasma membrane domains is poorly understood. Prior work has shown that restriction of microvilli to the apical aspect of epithelial cells requires the localized activation of the membrane-F-actin linking protein ezrin. Using an in vitro system, we now define a multi-step process whereby the kinase LOK specifically phosphorylates ezrin to activate it. Binding of PIP2 to ezrin induces a conformational change permitting the insertion of the LOK C-terminal domain to wedge apart the membrane and F-actin-binding domains of ezrin. The N-terminal LOK kinase domain can then access a site 40 residues distal from the consensus sequence that collectively direct phosphorylation of the appropriate threonine residue. We suggest that this elaborate mechanism ensures that ezrin is only phosphorylated at the plasma membrane, and with high specificity by the apically localized kinase LOK. DOI:http://dx.doi.org/10.7554/eLife.22759.001
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Affiliation(s)
- Thaher Pelaseyed
- Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Raghuvir Viswanatha
- Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States.,Department of Genetics, Harvard Medical School, Boston, United States
| | - Cécile Sauvanet
- Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Joshua J Filter
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Michael L Goldberg
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Anthony Bretscher
- Weill Institute for Molecular and Cell Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
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14
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Deletion of the Ste20-like kinase SLK in skeletal muscle results in a progressive myopathy and muscle weakness. Skelet Muscle 2017; 7:3. [PMID: 28153048 PMCID: PMC5288853 DOI: 10.1186/s13395-016-0119-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 12/26/2016] [Indexed: 12/16/2022] Open
Abstract
Background The Ste20-like kinase, SLK, plays an important role in cell proliferation and cytoskeletal remodeling. In fibroblasts, SLK has been shown to respond to FAK/Src signaling and regulate focal adhesion turnover through Paxillin phosphorylation. Full-length SLK has also been shown to be essential for embryonic development. In myoblasts, the overexpression of a dominant negative SLK is sufficient to block myoblast fusion. Methods In this study, we crossed the Myf5-Cre mouse model with our conditional SLK knockout model to delete SLK in skeletal muscle. A thorough analysis of skeletal muscle tissue was undertaken in order to identify defects in muscle development caused by the lack of SLK. Isometric force analysis was performed on adult knockout mice and compared to age-matched wild-type mice. Furthermore, cardiotoxin injections were performed followed by immunohistochemistry for myogenic markers to assess the efficiency muscle regeneration following SLK deletion. Results We show here that early deletion of SLK from the myogenic lineage does not markedly impair skeletal muscle development but delays the regenerative process. Interestingly, adult mice (~6 months) display an increase in the proportion of central nuclei and increased p38 activation. Furthermore, mice as young as 3 months old present with decreased force generation, suggesting that the loss of SLK impairs myofiber stability and function. Assessment of structural components revealed aberrant localization of focal adhesion proteins, such as FAK and paxillin. Our data show that the loss of SLK results in unstable myofibers resulting in a progressive myopathy. Additionally, the loss of SLK resulted in a delay in muscle regeneration following cardiotoxin injections. Conclusions Our results show that SLK is dispensable for muscle development and regeneration but is required for myofiber stability and optimal force generation. Electronic supplementary material The online version of this article (doi:10.1186/s13395-016-0119-1) contains supplementary material, which is available to authorized users.
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15
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Cybulsky AV, Guillemette J, Papillon J. Ste20-like kinase, SLK, activates the heat shock factor 1 - Hsp70 pathway. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1863:2147-55. [PMID: 27216364 DOI: 10.1016/j.bbamcr.2016.05.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/17/2016] [Accepted: 05/19/2016] [Indexed: 10/21/2022]
Abstract
Expression and activation of SLK increases during renal ischemia-reperfusion injury. When highly expressed, SLK signals via c-Jun N-terminal kinase and p38 to induce apoptosis, and it exacerbates apoptosis induced by ischemia-reperfusion injury. Overexpression of SLK in glomerular epithelial cells (GECs)/podocytes in vivo induces injury and proteinuria. In response to various stresses, cells enhance expression of chaperones or heat shock proteins (e.g. Hsp70), which are involved in the folding and maturation of newly synthesized proteins, and can refold denatured or misfolded proteins. We address the interaction of SLK with the heat shock factor 1 (HSF1)-Hsp70 pathway. Increased expression of SLK in GECs (following transfection) induced HSF1 transcriptional activity. Moreover, HSF1 transcriptional activity was increased by in vitro ischemia-reperfusion injury (chemical anoxia/recovery) and heat shock, and in both instances was amplified further by SLK overexpression. HSF1 binds to promoters of target genes, such as Hsp70 and induces their transcription. By analogy to HSF1, SLK stimulated Hsp70 expression. Hsp70 was also enhanced by anoxia/recovery and was further amplified by SLK overexpression. Induction of HSF1 and Hsp70 was dependent on the kinase activity of SLK, and was mediated via polo-like kinase-1. Transfection of constitutively active HSF1 enhanced Hsp70 expression and inhibited SLK-induced apoptosis. Conversely, the proapoptotic action of SLK was augmented by HSF1 shRNA, or the Hsp70 inhibitor, pifithrin-μ. In conclusion, increased expression/activity of SLK activates the HSF1-Hsp70 pathway. Hsp70 attenuates the primary proapoptotic effect of SLK. Modulation of chaperone expression may potentially be harnessed as cytoprotective therapy in renal cell injury.
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Affiliation(s)
- Andrey V Cybulsky
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada.
| | - Julie Guillemette
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
| | - Joan Papillon
- Department of Medicine, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
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16
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Leroy C, Belkina NV, Long T, Deruy E, Dissous C, Shaw S, Tulasne D. Caspase Cleavages of the Lymphocyte-oriented Kinase Prevent Ezrin, Radixin, and Moesin Phosphorylation during Apoptosis. J Biol Chem 2016; 291:10148-61. [PMID: 26945071 DOI: 10.1074/jbc.m116.721365] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Indexed: 11/06/2022] Open
Abstract
The lymphocyte-oriented kinase (LOK), also called serine threonine kinase 10 (STK10), is synthesized mainly in lymphocytes. It is involved in lymphocyte migration and polarization and can phosphorylate ezrin, radixin, and moesin (the ERM proteins). In a T lymphocyte cell line and in purified human lymphocytes, we found LOK to be cleaved by caspases during apoptosis. The first cleavage occurs at aspartic residue 332, located between the kinase domain and the coiled-coil regulation domain. This cleavage generates an N-terminal fragment, p50 N-LOK, containing the kinase domain and a C-terminal fragment, which is further cleaved during apoptosis. Although these cleavages preserve the entire kinase domain, p50 N-LOK displays no kinase activity. In apoptotic lymphocytes, caspase cleavages of LOK are concomitant with a decrease in ERM phosphorylation. When non-apoptotic lymphocytes from mice with homozygous and heterozygous LOK knockout were compared, the latter showed a higher level of ERM phosphorylation, but when apoptosis was induced, LOK(-/-) and LOK(+/-) lymphocytes showed the same low level, confirming in vivo that LOK-induced ERM phosphorylation is prevented during lymphocyte apoptosis. Our results demonstrate that cleavage of LOK during apoptosis abolishes its kinase activity, causing a decrease in ERM phosphorylation, crucial to the role of the ERM proteins in linking the plasma membrane to actin filaments.
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Affiliation(s)
- Catherine Leroy
- From the University of Lille, CNRS, Institut Pasteur de Lille, Unité Mixte de Recherche (UMR) 8161, Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | | | - Thavy Long
- the University of Lille, CNRS, INSERM, Centre Hospitalier Régional Universitaire de Lille, Institut Pasteur de Lille, U1019-UMR 8204, Center for Infection and Immunity of Lille, 59000 Lille, France
| | - Emeric Deruy
- the University of Lille, CNRS, INSERM, Centre Hospitalier Régional Universitaire de Lille, Institut Pasteur de Lille, U1019-UMR 8204, Center for Infection and Immunity of Lille, 59000 Lille, France
| | - Colette Dissous
- the University of Lille, CNRS, INSERM, Centre Hospitalier Régional Universitaire de Lille, Institut Pasteur de Lille, U1019-UMR 8204, Center for Infection and Immunity of Lille, 59000 Lille, France
| | - Stephen Shaw
- Experimental Immunology Branch Branches, NCI/National Institutes of Health, Bethesda, Maryland 20892, and
| | - David Tulasne
- From the University of Lille, CNRS, Institut Pasteur de Lille, Unité Mixte de Recherche (UMR) 8161, Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
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17
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Fokin AI, Klementeva TS, Nadezhdina ES, Burakov AV. SLK/LOSK kinase regulates cell motility independently of microtubule organization and Golgi polarization. Cytoskeleton (Hoboken) 2016; 73:83-92. [PMID: 26818812 DOI: 10.1002/cm.21276] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 10/16/2015] [Accepted: 01/20/2016] [Indexed: 12/31/2022]
Abstract
Cell motility is an essential complex process that requires actin and microtubule cytoskeleton reorganization and polarization. Such extensive rearrangement is closely related to cell polarization as a whole. The serine/threonine kinase SLK/LOSK is a potential regulator of cell motility, as it phosphorylates a series of cytoskeleton-bound proteins that collectively participate in the remodeling of migratory cell architecture. In this work, we report that SLK/LOSK is an indispensable regulator of cell locomotion that primarily acts through the small GTPase RhoA and the dynactin subunit p150(Glued). Both RhoA and dynactin affect cytoskeleton organization, polarization, and general cell locomotory activity to various extents. However, it seems that these events are independent of each other. Thus, SLK/LOSK kinase effectively functions as a switch that links all of the processes underlying cell motility to provide robust directional movement.
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Affiliation(s)
- Artem I Fokin
- A.N.Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskye Gory, Moscow, 119992, Russia
| | - Tatiana S Klementeva
- Institute of Protein Research of Russian Academy of Sciences, Moscow Region, Pushchino, Institutskaya Str, 4, 142290, Russia
| | - Elena S Nadezhdina
- A.N.Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskye Gory, Moscow, 119992, Russia.,Institute of Protein Research of Russian Academy of Sciences, Moscow Region, Pushchino, Institutskaya Str, 4, 142290, Russia
| | - Anton V Burakov
- A.N.Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskye Gory, Moscow, 119992, Russia
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18
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Jaberi A, Hooker E, Guillemette J, Papillon J, Kristof AS, Cybulsky AV. Identification of Tpr and α-actinin-4 as two novel SLK-interacting proteins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2539-52. [DOI: 10.1016/j.bbamcr.2015.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 06/11/2015] [Accepted: 06/17/2015] [Indexed: 01/05/2023]
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19
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Tse ACK, Li JW, Chan TF, Wu RSS, Lai KP. Hypoxia induces miR-210, leading to anti-apoptosis in ovarian follicular cells of marine medaka Oryzias melastigma. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 165:189-196. [PMID: 26074452 DOI: 10.1016/j.aquatox.2015.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/29/2015] [Accepted: 06/02/2015] [Indexed: 06/04/2023]
Abstract
Hypoxia is a major global problem that impairs reproductive functions and reduces the quality and quantity of gametes and the fertilization success of marine fish. Nevertheless, the detailed molecular mechanism underlying hypoxia-induced female reproductive impairment remains largely unknown. There is increasing evidence that miRNA is vital in regulating ovarian functions and is closely associated with female fertility in humans. Certain miRNAs that regulate apoptotic genes can be induced by hypoxia, resulting in cell apoptosis. Using primary ovarian follicular cells of the marine medaka, Oryzias melastigma, as a model, we investigated the response of miR-210 to hypoxic stress in ovarian tissues to see if it would interrupt reproductive functions. A significant induction of miR-210 was found in primary ovarian follicular cells exposed to hypoxia, and gene ontology analysis further highlighted the potential roles of miR-210 in cell proliferation, cell differentiation, and cell apoptosis. A number of miR-210 target apoptotic genes, including Deleted in liver cancer 1 protein (DLC1), STE20-like serine/threonine-protein kinase (SLK), tumor necrosis factor receptor superfamily member 10b (TNFRSF10B), RNA binding motif protein 25 (RBM25), and Ubiquitin-specific-processing protease 7 (USP7), were identified. We further showed that ectopic expression of miR-210 would result in down-regulation of these apoptotic genes. On the other hand, the inhibition of miR-210 promoted apoptotic cell death and the expression of apoptotic marker - caspase 3 in follicular cells under hypoxic treatment, supporting the regulatory role of miR-210 in ovarian cell apoptosis. This study provides new insights on how hypoxia induces miR-210, leading to anti-apoptosis in ovarian follicular cells in fish, which is fundamentally important in environmental sciences and reproductive biology.
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Affiliation(s)
- Anna Chung-Kwan Tse
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China; State Key Laboratory in Marine Pollution, Hong Kong SAR, China
| | - Jing-Woei Li
- School of Life Sciences, Hong Kong Bioinformatics Centre, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Ting-Fung Chan
- School of Life Sciences, Hong Kong Bioinformatics Centre, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Rudolf Shiu-Sun Wu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China; State Key Laboratory in Marine Pollution, Hong Kong SAR, China
| | - Keng-Po Lai
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China; State Key Laboratory in Marine Pollution, Hong Kong SAR, China.
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20
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Panneton V, Nath A, Sader F, Delaunay N, Pelletier A, Maier D, Oh K, Hipfner DR. Regulation of Catalytic and Non-catalytic Functions of the Drosophila Ste20 Kinase Slik by Activation Segment Phosphorylation. J Biol Chem 2015; 290:20960-20971. [PMID: 26170449 DOI: 10.1074/jbc.m115.645952] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Indexed: 01/21/2023] Open
Abstract
Protein kinases carry out important functions in cells both by phosphorylating substrates and by means of regulated non-catalytic activities. Such non-catalytic functions have been ascribed to many kinases, including some members of the Ste20 family. The Drosophila Ste20 kinase Slik phosphorylates and activates Moesin in developing epithelial tissues to promote epithelial tissue integrity. It also functions non-catalytically to promote epithelial cell proliferation and tissue growth. We carried out a structure-function analysis to determine how these two distinct activities of Slik are controlled. We find that the conserved C-terminal coiled-coil domain of Slik, which is necessary and sufficient for apical localization of the kinase in epithelial cells, is not required for Moesin phosphorylation but is critical for the growth-promoting function of Slik. Slik is auto- and trans-phosphorylated in vivo. Phosphorylation of at least two of three conserved sites in the activation segment is required for both efficient catalytic activity and non-catalytic signaling. Slik function is thus dependent upon proper localization of the kinase via the C-terminal coiled-coil domain and activation via activation segment phosphorylation, which enhances both phosphorylation of substrates like Moesin and engagement of effectors of its non-catalytic growth-promoting activity.
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Affiliation(s)
- Vincent Panneton
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada
| | - Apurba Nath
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada
| | - Fadi Sader
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Nathalie Delaunay
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Ariane Pelletier
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Dominic Maier
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 2B2, Canada
| | - Karen Oh
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - David R Hipfner
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 2B2, Canada; Department of Medicine, Université de Montréal, Montreal, Quebec H3C 3J7, Canada.
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21
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Baron KD, Al-Zahrani K, Conway J, Labrèche C, Storbeck CJ, Visvader JE, Sabourin LA. Recruitment and activation of SLK at the leading edge of migrating cells requires Src family kinase activity and the LIM-only protein 4. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1683-92. [PMID: 25882817 DOI: 10.1016/j.bbamcr.2015.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/20/2015] [Accepted: 04/03/2015] [Indexed: 12/26/2022]
Abstract
The Ste20-like kinase SLK plays a pivotal role in cell migration and focal adhesion turnover and is regulated by the LIM domain-binding proteins Ldb1 and Ldb2. These adapter proteins have been demonstrated to interact with LMO4 in the organization of transcriptional complexes. Therefore, we have assessed the ability of LMO4 to also interact and regulate SLK activity. Our data show that LMO4 can directly bind to SLK and activate its kinase activity in vitro and in vivo. LMO4 can be co-precipitated with SLK following the induction of cell migration by scratch wounding and Cre-mediated deletion of LMO4 in conditional LMO4(fl/fl) fibroblasts inhibits cell migration and SLK activation. Deletion of LMO4 impairs Ldb1 and SLK recruitment to the leading edge of migrating cells. Supporting this, Src/Yes/Fyn-deficient cells (SYF) expressing very low levels of LMO4 do not recruit SLK to the leading edge. Re-expression of wildtype Myc-LMO4 in SYF cells, but not a mutant version, restores SLK localization and kinase activity. Overall, our data suggest that activation of SLK by haptotactic signals requires its recruitment to the leading edge by LMO4 in a Src-dependent manner. Furthermore, this establishes a novel cytosolic role for the transcriptional co-activator LMO4.
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Affiliation(s)
- Kyla D Baron
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Khalid Al-Zahrani
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Jillian Conway
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Cédrik Labrèche
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Christopher J Storbeck
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Jane E Visvader
- Walter and Eliza Hall Institute Biotechnology Centre, Bundoora, Victoria 3086, Australia
| | - Luc A Sabourin
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, Canada.
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22
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Al-Zahrani KN, Sekhon P, Tessier DR, Yockell-Lelievre J, Pryce BR, Baron KD, Howe GA, Sriram RK, Daniel K, Mckay M, Lo V, Quizi J, Addison CL, Gruslin A, Sabourin LA. Essential role for the SLK protein kinase in embryogenesis and placental tissue development. Dev Dyn 2014; 243:640-51. [PMID: 24868594 DOI: 10.1002/dvdy.24106] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Over the past decade, the Ste20-like kinase SLK, has been implicated in several signaling processes. SLK repression has been shown to impair cell cycle kinetics and inhibit FAK-mediated cell migration. Here, using a gene trapped allele, we have generated mice expressing a truncated form of the SLK kinase. RESULTS Our results show that an SLK-LacZ fusion protein is expressed in embryonic stem cells and in embryos throughout development. We find that the SLK-LacZ fusion protein is less efficient at phosphorylating substrates resulting in reduced cell proliferation within the embryos and angiogenic defects in the placentae of the homozygous mutant animals at embryonic day (E) 12.5. This results in marked developmental defects and apoptotic lesions in the embryos by E14.5. CONCLUSIONS Homozygotes expressing the SLK-LacZ fusion protein present with an embryonic lethal phenotype occurring between E12.5 and E14.5. Overall, we demonstrate a requirement for SLK kinase activity in the developing embryo and placenta.
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23
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Chen X, Wei S, Ma Y, Lu J, Niu G, Xue Y, Chen X, Yang F. Quantitative proteomics analysis identifies mitochondria as therapeutic targets of multidrug-resistance in ovarian cancer. Am J Cancer Res 2014; 4:1164-75. [PMID: 25285166 PMCID: PMC4183995 DOI: 10.7150/thno.8502] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 03/14/2014] [Indexed: 12/31/2022] Open
Abstract
Doxorubicin is a widely used chemotherapeutic agent for the treatment of a variety of solid tumors. However, resistance to this anticancer drug is a major obstacle to the effective treatment of tumors. As mitochondria play important roles in cell life and death, we anticipate that mitochondria may be related to drug resistance. Here, stable isotope labeling by amino acids in cell culture (SILAC)-based quantitative proteomic strategy was applied to compare mitochondrial protein expression in doxorubicin sensitive OVCAR8 cells and its doxorubicin-resistant variant NCI_ADR/RES cells. A total of 2085 proteins were quantified, of which 122 proteins displayed significant changes in the NCI_ADR/RES cells. These proteins participated in a variety of cell processes including cell apoptosis, substance metabolism, transport, detoxification and drug metabolism. Then qRT-PCR and western blot were applied to validate the differentially expressed proteins quantified by SILAC. Further functional studies with RNAi demonstrated TOP1MT, a mitochondrial protein participated in DNA repair, was involved in doxorubicin resistance in NCI_ADR/RES cells. Besides the proteomic study, electron microscopy and fluorescence analysis also observed that mitochondrial morphology and localization were greatly altered in NCI_ADR/RES cells. Mitochondrial membrane potential was also decreased in NCI_ADR/RES cells. All these results indicate that mitochondrial function is impaired in doxorubicin-resistant cells and mitochondria play an important role in doxorubicin resistance. This research provides some new information about doxorubicin resistance, indicating that mitochondria could be therapeutic targets of doxorubicin resistance in ovarian cancer cells.
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Identification and characterization of a Ste20-like kinase in Artemia and its role in the developmental regulation and resistance to environmental stress. PLoS One 2014; 9:e92234. [PMID: 24637947 PMCID: PMC3956927 DOI: 10.1371/journal.pone.0092234] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 02/19/2014] [Indexed: 12/01/2022] Open
Abstract
Background To adapt to extreme environments, the crustacean Artemia has evolved two alternative reproductive pathways. During ovoviviparous (direct) development, nauplius larvae are produced. In contrast, Artemia females release encysted diapause embryos (cysts) via the oviparous pathway. To date, the cellular mechanisms that regulate stress resistance of Artemia remain largely unknown. Ste20-like kinase (SLK) participates in multiple biological processes, including stress responses, apoptosis, and cell cycle progression. Principal Finding We isolated and characterized a member of the SLK superfamily termed ArSLK from Artemia parthenogenetica. The ArSLK gene is transcribed throughout both ovoviviparous and oviparous development; however, the protein is located mainly in the nuclei of stress-resistant diapause cysts, unlike the nauplii and nauplius-destined embryos where it is cytoplasmic. Interestingly, exposure of nauplii to heat shock, acidic pH, and UV irradiation induced the translocation of ArSLK from cytoplasm to nucleus. This translocation was reversed following stress removal. Moreover, under physiologically-stressful conditions, the nauplius larvae produced by adults after gene knockdown of endogenous ArSLK by RNAi, lost the ability of free-swimming much earlier than those of control larvae from females injected with GFP dsRNA. Conclusions/Significance Taken together, this study demonstrated that trafficking of ArSLK between the cytoplasm and the nucleus participates in regulating the stress resistance of Artemia. Our findings may provide significant insight into the functions of members of the SLK superfamily.
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Hast BE, Cloer EW, Goldfarb D, Li H, Siesser PF, Yan F, Walter V, Zheng N, Hayes DN, Major MB. Cancer-derived mutations in KEAP1 impair NRF2 degradation but not ubiquitination. Cancer Res 2013; 74:808-17. [PMID: 24322982 DOI: 10.1158/0008-5472.can-13-1655] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
NRF2 is a transcription factor that mediates stress responses. Oncogenic mutations in NRF2 localize to one of its two binding interfaces with KEAP1, an E3 ubiquitin ligase that promotes proteasome-dependent degradation of NRF2. Somatic mutations in KEAP1 occur commonly in human cancer, where KEAP1 may function as a tumor suppressor. These mutations distribute throughout the KEAP1 protein but little is known about their functional impact. In this study, we characterized 18 KEAP1 mutations defined in a lung squamous cell carcinoma tumor set. Four mutations behaved as wild-type KEAP1, thus are likely passenger events. R554Q, W544C, N469fs, P318fs, and G333C mutations attenuated binding and suppression of NRF2 activity. The remaining mutations exhibited hypomorphic suppression of NRF2, binding both NRF2 and CUL3. Proteomic analysis revealed that the R320Q, R470C, G423V, D422N, G186R, S243C, and V155F mutations augmented the binding of KEAP1 and NRF2. Intriguingly, these "super-binder" mutants exhibited reduced degradation of NRF2. Cell-based and in vitro biochemical analyses demonstrated that despite its inability to suppress NRF2 activity, the R320Q "superbinder" mutant maintained the ability to ubiquitinate NRF2. These data strengthen the genetic interactions between KEAP1 and NRF2 in cancer and provide new insight into KEAP1 mechanics.
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Affiliation(s)
- Bridgid E Hast
- Authors' Affiliations: Department of Cell Biology and Physiology; Lineberger Comprehensive Cancer Center; and Division of Medical Oncology, Department of Internal Medicine and Otolaryngology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine; Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, Washington
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Zhapparova ON, Fokin AI, Vorobyeva NE, Bryantseva SA, Nadezhdina ES. Ste20-like protein kinase SLK (LOSK) regulates microtubule organization by targeting dynactin to the centrosome. Mol Biol Cell 2013; 24:3205-14. [PMID: 23985322 PMCID: PMC3806656 DOI: 10.1091/mbc.e13-03-0137] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The protein kinase SLK (LOSK) phosphorylates the 1A isoform of the p150Glued subunit of dynactin and targets it to the centrosome, where it maintains microtubule radial organization. In addition, dynactin phosphorylation is involved in Golgi reorientation in polarized cells. The microtubule- and centrosome-associated Ste20-like kinase (SLK; long Ste20-like kinase [LOSK]) regulates cytoskeleton organization and cell polarization and spreading. Its inhibition causes microtubule disorganization and release of centrosomal dynactin. The major function of dynactin is minus end–directed transport along microtubules in a complex with dynein motor. In addition, dynactin is required for maintenance of the microtubule radial array in interphase cells, and depletion of its centrosomal pool entails microtubule disorganization. Here we demonstrate that SLK (LOSK) phosphorylates the p150Glued subunit of dynactin and thus targets it to the centrosome, where it maintains microtubule radial organization. We show that phosphorylation is required only for centrosomal localization of p150Glued and does not affect its microtubule-organizing properties: artificial targeting of nonphosphorylatable p150Glued to the centrosome restores microtubule radial array in cells with inhibited SLK (LOSK). The phosphorylation site is located in a microtubule-binding region that is variable for two isoforms (1A and 1B) of p150Glued expressed in cultured fibroblast-like cells (isoform 1B lacks 20 amino acids in the basic microtubule-binding domain). The fact that SLK (LOSK) phosphorylates only a minor isoform 1A of p150Glued suggests that transport and microtubule-organizing functions of dynactin are distinctly divided between the two isoforms. We also show that dynactin phosphorylation is involved in Golgi reorientation in polarized cells.
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Affiliation(s)
- Olga N Zhapparova
- A. N. Belozersky Institute for Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia Institute of Protein Research, Russian Academy of Sciences, Moscow 117334, Russia
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Storbeck CJ, Al-Zahrani KN, Sriram R, Kawesa S, O'Reilly P, Daniel K, McKay M, Kothary R, Tsilfidis C, Sabourin LA. Distinct roles for Ste20-like kinase SLK in muscle function and regeneration. Skelet Muscle 2013; 3:16. [PMID: 23815977 PMCID: PMC3733878 DOI: 10.1186/2044-5040-3-16] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 05/02/2013] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Cell growth and terminal differentiation are controlled by complex signaling systems that regulate the tissue-specific expression of genes controlling cell fate and morphogenesis. We have previously reported that the Ste20-like kinase SLK is expressed in muscle tissue and is required for cell motility. However, the specific function of SLK in muscle tissue is still poorly understood. METHODS To gain further insights into the role of SLK in differentiated muscles, we expressed a kinase-inactive SLK from the human skeletal muscle actin promoter. Transgenic muscles were surveyed for potential defects. Standard histological procedures and cardiotoxin-induced regeneration assays we used to investigate the role of SLK in myogenesis and muscle repair. RESULTS High levels of kinase-inactive SLK in muscle tissue produced an overall decrease in SLK activity in muscle tissue, resulting in altered muscle organization, reduced litter sizes, and reduced breeding capacity. The transgenic mice did not show any differences in fiber-type distribution but displayed enhanced regeneration capacity in vivo and more robust differentiation in vitro. CONCLUSIONS Our results show that SLK activity is required for optimal muscle development in the embryo and muscle physiology in the adult. However, reduced kinase activity during muscle repair enhances regeneration and differentiation. Together, these results suggest complex and distinct roles for SLK in muscle development and function.
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Al-Zahrani KN, Baron KD, Sabourin LA. Ste20-like kinase SLK, at the crossroads: a matter of life and death. Cell Adh Migr 2012; 7:1-10. [PMID: 23154402 DOI: 10.4161/cam.22495] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Reorganization of the cytoskeleton is necessary for apoptosis, proliferation, migration, development and tissue repair. However, it is well established that mutations or overexpression of key regulators contribute to the phenotype and progression of several pathologies such as cancer. For instance, c-src mutations and the overexpression of FAK have been implicated in the invasive and metastatic process, suggesting that components of the motility system may represent a new class of therapeutic targets. Over the last several years, we and others have established distinct roles for the Ste20-like kinase SLK, encompassing apoptosis, growth, motility and development. Here, we review the SLK field from its initial cloning to the most recent findings from our laboratory. We summarize the various roles of SLK and the biochemical mechanisms that regulate its activity. These various findings reveal very complex functions and pattern of regulation for SLK in development and cancer, making it a potential therapeutic target.
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Luhovy AY, Jaberi A, Papillon J, Guillemette J, Cybulsky AV. Regulation of the Ste20-like kinase, SLK: involvement of activation segment phosphorylation. J Biol Chem 2011; 287:5446-58. [PMID: 22203681 DOI: 10.1074/jbc.m111.302018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression and activation of the Ste20-like kinase, SLK, is increased during kidney development and recovery from ischemic acute kidney injury. SLK promotes apoptosis, and it may regulate cell survival during injury or repair. This study addresses the role of phosphorylation in the regulation of kinase activity. We mutated serine and threonine residues in the putative activation segment of the SLK catalytic domain and expressed wild type (WT) and mutant proteins in COS-1 or glomerular epithelial cells. Compared with SLK WT, the T183A, S189A, and T183A/S189A mutants showed reduced in vitro kinase activity. SLK WT, but not mutants, increased activation-specific phosphorylation of c-Jun N-terminal kinase (JNK) and p38 kinase. Similarly, SLK WT stimulated activator protein-1 reporter activity, but activation of activator protein-1 by the three SLK mutants was ineffective. To test if homodimerization of SLK affects phosphorylation, the cDNA encoding SLK amino acids 1-373 (which include the catalytic domain) was fused with a cDNA for a modified FK506-binding protein, Fv (Fv-SLK 1-373). After transfection, the addition of AP20187 (an FK506 analog) induced regulated dimerization of Fv-SLK 1-373. AP20187-stimulated dimerization enhanced the kinase activity of Fv-SLK 1-373 WT. In contrast, kinase activity of Fv-SLK 1-373 T183A/S189A was weak and was not enhanced after dimerization. Finally, apoptosis was increased after expression of Fv-SLK 1-373 WT but not T183A/S189A. Thus, phosphorylation of Thr-183 and Ser-189 plays a key role in the activation and signaling of SLK and could represent a target for novel therapeutic approaches to renal injury.
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Affiliation(s)
- Artem Y Luhovy
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec H3A 1A1, Canada
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Cabrita MA, Jones LM, Quizi JL, Sabourin LA, McKay BC, Addison CL. Focal adhesion kinase inhibitors are potent anti-angiogenic agents. Mol Oncol 2011; 5:517-26. [PMID: 22075057 DOI: 10.1016/j.molonc.2011.10.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2011] [Accepted: 10/12/2011] [Indexed: 11/17/2022] Open
Abstract
Focal adhesion kinase (FAK), a cytoplasmic tyrosine kinase and scaffold protein localized to focal adhesions, is uniquely positioned at the convergence point of integrin and receptor tyrosine kinase signal transduction pathways. FAK is overexpressed in many tumor cells, hence various inhibitors targeting its activity have been tested for anti-tumor activity. However, the direct effects of these pharmacologic agents on the endothelial cells of the vasculature have not been examined. Using primary human umbilical vein endothelial cells (HUVEC), we characterized the effects of two FAK inhibitors, PF-573,228 and FAK Inhibitor 14 on essential processes for angiogenesis, such as migration, proliferation, viability and endothelial cell tube formation. We observed that treatment with either FAK Inhibitor 14 or PF-573,228 resulted in reduced HUVEC viability, migration and tube formation in response to vascular endothelial growth factor (VEGF). Furthermore, we found that PF-573,228 had the added ability to induce apoptosis of endothelial cells within 36 h post-drug administration even in the continued presence of VEGF stimulation. FAK inhibitors also resulted in modification of the actin cytoskeleton within HUVEC, with observed increased stress fiber formation in the presence of drug. Given that endothelial cells were sensitive to FAK inhibitors at concentrations well below those reported to inhibit tumor cell migration, we confirmed their ability to inhibit endothelial-derived FAK autophosphorylation and FAK-mediated phosphorylation of recombinant paxillin at these doses. Taken together, our data indicate that small molecule inhibitors of FAK are potent anti-angiogenic agents and suggest their utility in combinatorial therapeutic approaches targeting tumor angiogenesis.
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Affiliation(s)
- Miguel A Cabrita
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada K1H 8L6
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Takeda K, Naguro I, Nishitoh H, Matsuzawa A, Ichijo H. Apoptosis signaling kinases: from stress response to health outcomes. Antioxid Redox Signal 2011; 15:719-61. [PMID: 20969480 DOI: 10.1089/ars.2010.3392] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Apoptosis is a highly regulated process essential for the development and homeostasis of multicellular organisms. Whereas caspases, a large family of intracellular cysteine proteases, play central roles in the execution of apoptosis, other proapoptotic and antiapoptotic regulators such as the members of the Bcl-2 family are also critically involved in the regulation of apoptosis. A large body of evidence has revealed that a number of protein kinases are among such regulators and regulate cellular sensitivity to various proapoptotic signals at multiple steps in apoptosis. However, recent progress in the analysis of these apoptosis signaling kinases demonstrates that they generally act as crucial regulators of diverse cellular responses to a wide variety of stressors, beyond their roles in apoptosis regulation. In this review, we have cataloged apoptosis signaling kinases involved in cellular stress responses on the basis of their ability to induce apoptosis and discuss their roles in stress responses with particular emphasis on health outcomes upon their dysregulation.
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Affiliation(s)
- Kohsuke Takeda
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, Strategic Approach to Drug Discovery and Development in Pharmaceutical Sciences, Global Center of Excellence Program and Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, The University of Tokyo, Tokyo, Japan.
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Delarosa S, Guillemette J, Papillon J, Han YS, Kristof AS, Cybulsky AV. Activity of the Ste20-like kinase, SLK, is enhanced by homodimerization. Am J Physiol Renal Physiol 2011; 301:F554-64. [PMID: 21677149 DOI: 10.1152/ajprenal.00062.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The expression and activation of the Ste20-like kinase, SLK, is increased during renal development and recovery from ischemic acute renal failure. SLK promotes apoptosis, and during renal injury and repair, transcriptional induction or posttranscriptional control of SLK may, therefore, regulate cell survival. SLK contains protein interaction (coiled-coil) domains, suggesting that posttranslational homodimerization may also modulate SLK activity. We therefore expressed coiled-coil regions in the C-terminal domain of SLK as fusion proteins and demonstrated their homodimerization. By gel-filtration chromatography, endogenous and heterologously expressed SLK were detected in a macromolecular protein complex. To test the role of homodimerization in kinase activation, we constructed a fusion protein consisting of the SLK catalytic domain (amino acids 1-373) and a modified FK506 binding protein, Fv (Fv-SLK 1-373). Addition of AP20187 (an analog of FK506) enhanced the homodimerization of Fv-SLK 1-373. In an in vitro kinase assay, the dimeric Fv-SLK 1-373 displayed greater kinase activity than the monomeric form. In cells expressing Fv-SLK 1-373, homodimerization increased activation-specific phosphorylation of the proapoptotic kinases, c-Jun N-terminal kinase and p38 kinase. Compared with the monomer, dimeric Fv-SLK 1-373 enhanced the activation of a Bax promoter-luciferase reporter. Finally, expression of Fv-SLK 1-373 induced apoptosis, and the effect was increased by homodimerization. Thus the activity, downstream signaling, and functional effects of SLK are enhanced by dimerization of the kinase domain.
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Affiliation(s)
- Sierra Delarosa
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
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Keshet Y, Seger R. The MAP kinase signaling cascades: a system of hundreds of components regulates a diverse array of physiological functions. Methods Mol Biol 2010; 661:3-38. [PMID: 20811974 DOI: 10.1007/978-1-60761-795-2_1] [Citation(s) in RCA: 422] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Sequential activation of kinases within the mitogen-activated protein (MAP) kinase (MAPK) cascades is a common, and evolutionary-conserved mechanism of signal transduction. Four MAPK cascades have been identified in the last 20 years and those are usually named according to the MAPK components that are the central building blocks of each of the cascades. These are the extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-Terminal kinase (JNK), p38, and ERK5 cascades. Each of these cascades consists of a core module of three tiers of protein kinases termed MAPK, MAPKK, and MAP3K, and often two additional tiers, the upstream MAP4K and the downstream MAPKAPK, which can complete five tiers of each cascade in certain cell lines or stimulations. The transmission of the signal via each cascade is mediated by sequential phosphorylation and activation of the components in the sequential tiers. These cascades cooperate in transmitting various extracellular signals and thus control a large number of distinct and even opposing cellular processes such as proliferation, differentiation, survival, development, stress response, and apoptosis. One way by which the specificity of each cascade is regulated is through the existence of several distinct components in each tier of the different cascades. About 70 genes, which are each translated to several alternatively spliced isoforms, encode the entire MAPK system, and allow the wide array of cascade's functions. These components, their regulation, as well as their involvement together with other mechanisms in the determination of signaling specificity by the MAPK cascade is described in this review. Mis-regulation of the MAPKs signals usually leads to diseases such as cancer and diabetes; therefore, studying the mechanisms of specificity-determination may lead to better understanding of these signaling-related diseases.
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Affiliation(s)
- Yonat Keshet
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel
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Cybulsky AV, Takano T, Papillon J, Guillemette J, Herzenberg AM, Kennedy CRJ. Podocyte injury and albuminuria in mice with podocyte-specific overexpression of the Ste20-like kinase, SLK. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2290-9. [PMID: 20889563 DOI: 10.2353/ajpath.2010.100263] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SLK expression and activity are increased during kidney development and recovery from renal ischemia-reperfusion injury. In cultured cells, SLK promotes F-actin destabilization as well as apoptosis, partially via the p38 kinase pathway. To better understand the effects of SLK in vivo, a transgenic mouse model was developed where SLK was expressed in a podocyte-specific manner using the mouse nephrin promoter. Offspring of four founder mice carried the SLK transgene. Among male transgenic mice, 66% developed albuminuria at approximately 3 months of age, and the albuminuric mice originated from three of four founders. Overall, the male transgenic mice demonstrated about fivefold greater urinary albumin/creatinine compared with male non-transgenic mice. Transgenic and non-transgenic female mice did not develop albuminuria, suggesting that females were less susceptible to glomerular filtration barrier damage than their male counterparts. In transgenic mice, electron microscopy revealed striking podocyte injury, including poorly formed or effaced foot processes, and edematous and vacuolated cell bodies. By immunoblotting, nephrin expression was decreased in glomeruli of the albuminuric transgenic mice. Activation-specific phosphorylation of p38 was increased in transgenic mice compared with non-transgenic animals. Glomeruli of SLK transgenic mice showed around 30% fewer podocytes, and a reduction in F-actin compared with control glomeruli. Thus, podocyte SLK overexpression in vivo results in injury and podocyte loss, consistent with the effects of SLK in cultured cells.
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Affiliation(s)
- Andrey V Cybulsky
- Department of Medicine, McGill University Health Centre, McGill University, Division of Nephrology, Royal Victoria Hospital, 687 Pine Avenue West, Montreal, Quebec, Canada H3A 1A1.
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Exon-level transcriptome profiling in murine breast cancer reveals splicing changes specific to tumors with different metastatic abilities. PLoS One 2010; 5:e11981. [PMID: 20700505 PMCID: PMC2917353 DOI: 10.1371/journal.pone.0011981] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Accepted: 07/08/2010] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Breast cancer is the second most frequent type of cancer affecting women. We are increasingly aware that changes in mRNA splicing are associated with various characteristics of cancer. The most deadly aspect of cancer is metastasis, the process by which cancer spreads from the primary tumor to distant organs. However, little is known specifically about the involvement of alternative splicing in the formation of macroscopic metastases. Our study investigates transcript isoform changes that characterize tumors of different abilities to form growing metastases. METHODS AND FINDINGS To identify alternative splicing events (ASEs) that are associated with the fully metastatic phenotype in breast cancer, we used Affymetrix Exon Microarrays to profile mRNA isoform variations genome-wide in weakly metastatic (168FARN and 4T07) and highly metastatic (4T1) mammary carcinomas. Statistical analysis identified significant expression changes in 7606 out of 155,994 (4%) exons and in 1725 out of 189,460 (1%) intronic regions, which affect 2623 out of 16,654 (16%) genes. These changes correspond to putative alternative isoforms-several of which are novel-that are differentially expressed between tumors of varying metastatic phenotypes. Gene pathway analysis showed that 1224 of genes expressing alternative isoforms were involved in cell growth, cell interactions, cell proliferation, cell migration and cell death and have been previously linked to cancers and genetic disorders. We chose ten predicted splice variants for RT-PCR validation, eight of which were successfully confirmed (MED24, MFI2, SRRT, CD44, CLK1 and HNRNPH1). These include three novel intron retentions in CD44, a gene in which isoform variations have been previously associated with the metastasis of several cancers. CONCLUSION Our findings reveal that various genes are differently spliced and/or expressed in association with the metastatic phenotype of tumor cells. Identification of metastasis-specific isoforms may contribute to the development of improved breast cancer stage identification and targeted therapies.
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Karpov PA, Emets AI, Matusov VG, Nyporko AY, Nadezhdina ES, Blume YB. Bioinformatics search for plant homologues of Ste20-like serine/threonine protein kinases. CYTOL GENET+ 2009. [DOI: 10.3103/s0095452709060097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Schouest KR, Kurasawa Y, Furuta T, Hisamoto N, Matsumoto K, Schumacher JM. The germinal center kinase GCK-1 is a negative regulator of MAP kinase activation and apoptosis in the C. elegans germline. PLoS One 2009; 4:e7450. [PMID: 19826475 PMCID: PMC2757678 DOI: 10.1371/journal.pone.0007450] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 09/22/2009] [Indexed: 11/25/2022] Open
Abstract
The germinal center kinases (GCK) constitute a large, highly conserved family of proteins that has been implicated in a wide variety of cellular processes including cell growth and proliferation, polarity, migration, and stress responses. Although diverse, these functions have been attributed to an evolutionarily conserved role for GCKs in the activation of ERK, JNK, and p38 MAP kinase pathways. In addition, multiple GCKs from different species promote apoptotic cell death. In contrast to these paradigms, we found that a C. elegans GCK, GCK-1, functions to inhibit MAP kinase activation and apoptosis in the C. elegans germline. In the absence of GCK-1, a specific MAP kinase isoform is ectopically activated and oocytes undergo abnormal development. Moreover, GCK-1- deficient animals display a significant increase in germ cell death. Our results suggest that individual germinal center kinases act in mechanistically distinct ways and that these functions are likely to depend on organ- and developmental-specific contexts.
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Affiliation(s)
- Katherine R. Schouest
- Department of Genetics, The University of M.D. Anderson Cancer Center, Houston, Texas, United States of America
- Genes and Development Program, University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas, United States of America
| | - Yasuhiro Kurasawa
- Department of Genetics, The University of M.D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Tokiko Furuta
- Department of Genetics, The University of M.D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Naoki Hisamoto
- Department of Molecular Biology, Graduate School of Science, Institute for Advanced Research, Nagoya University, Nagoya, Japan
- CREST, Japan Science and Technology Corporation, Chikusa-ku, Nagoya, Japan
| | - Kunihiro Matsumoto
- Department of Molecular Biology, Graduate School of Science, Institute for Advanced Research, Nagoya University, Nagoya, Japan
- CREST, Japan Science and Technology Corporation, Chikusa-ku, Nagoya, Japan
| | - Jill M. Schumacher
- Department of Genetics, The University of M.D. Anderson Cancer Center, Houston, Texas, United States of America
- Genes and Development Program, University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas, United States of America
- * E-mail: .
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Storbeck CJ, Wagner S, O'Reilly P, McKay M, Parks RJ, Westphal H, Sabourin LA. The Ldb1 and Ldb2 transcriptional cofactors interact with the Ste20-like kinase SLK and regulate cell migration. Mol Biol Cell 2009; 20:4174-82. [PMID: 19675209 PMCID: PMC2754931 DOI: 10.1091/mbc.e08-07-0707] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 07/14/2009] [Accepted: 07/30/2009] [Indexed: 11/11/2022] Open
Abstract
Cell migration involves a multitude of signals that converge on cytoskeletal reorganization, essential for development, immune responses, and tissue repair. Here, we show that the microtubule-associated Ste20 kinase SLK, required for cell migration, interacts with the LIM domain binding transcriptional cofactor proteins Ldb1/CLIM2 and Ldb2/CLIM1/NLI. We demonstrate that Ldb1 and 2 bind directly to the SLK carboxy-terminal AT1-46 homology domain in vitro and in vivo. We find that Ldb1 and -2 colocalize with SLK in migrating cells and that both knockdown and overexpression of either factor results in increased motility. Supporting this, knockdown of Ldb1 increases focal adhesion turnover and enhances migration in fibroblasts. We propose that Ldb1/2 function to maintain SLK in an inactive state before its activation. These findings highlight a novel function for Ldb1 and -2 and expand their role to include the control of cell migration.
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Affiliation(s)
- Chris J. Storbeck
- *Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Simona Wagner
- *Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Paul O'Reilly
- *Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Marlene McKay
- Ottawa Hospital Research Institute, Ottawa, Ontario K1Y 4E9, Canada; and
| | - Robin J. Parks
- Ottawa Hospital Research Institute, Ottawa, Ontario K1Y 4E9, Canada; and
| | - Heiner Westphal
- Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Development, Bethesda, MD 20892
| | - Luc A. Sabourin
- *Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
- Ottawa Hospital Research Institute, Ottawa, Ontario K1Y 4E9, Canada; and
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39
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Cybulsky AV, Takano T, Guillemette J, Papillon J, Volpini RA, Di Battista JA. The Ste20-like kinase SLK promotes p53 transactivation and apoptosis. Am J Physiol Renal Physiol 2009; 297:F971-80. [DOI: 10.1152/ajprenal.00294.2009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Expression and activity of the germinal center SLK are increased during kidney development and recovery from renal ischemia-reperfusion injury. SLK promotes apoptosis, in part, via pathway(s) involving apoptosis signal-regulating kinase-1 and p38 mitogen-activated protein kinase. This study addresses the role of p53 as a potential effector of SLK. p53 transactivation was measured after transient transfection of a luciferase reporter plasmid that contains a p53 cis-acting enhancer element. Overexpression of SLK in COS-1 cells and cotransfection of SLK and p53-wild type (wt) cDNAs in glomerular epithelial cells (GECs) stimulated p53 transactivational activity, as measured by a p53 response element-driven luciferase reporter. In GECs, chemical anoxia followed by glucose reexposure (in vitro ischemia-reperfusion) increased p53 reporter activity, and this increase was amplified by overexpression of SLK. Expression of SLK induced p53 phosphorylation on serine (S)-33 and S315. In GECs, cotransfection of SLK with p53-wt, p53-S33A, p53-S315A, or p53-S33A+S315A mutants showed that only the double mutation abolished the SLK-induced increase in p53 reporter activity. SLK-induced stimulation of p53 reporter activity was attenuated by inhibition of JNK. Overexpression of SLK amplified apoptosis induced by subjecting cells to in vitro ischemia-reperfusion injury, while ectopic expression of a dominant negative SLK mutant attenuated the ischemia-reperfusion-induced apoptosis. The p53 transactivation inhibitor pifithrin-α significantly attenuated the amount of apoptosis after ischemia-reperfusion and SLK overexpression. Thus SLK induces p53 phosphorylation and transactivation, which enhances apoptosis after in vitro ischemia-reperfusion injury.
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Affiliation(s)
- Andrey V. Cybulsky
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Tomoko Takano
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Julie Guillemette
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Joan Papillon
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Rildo A. Volpini
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - John A. Di Battista
- Department of Medicine, McGill University Health Centre, McGill University, Montreal, Quebec, Canada
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Mammalian sterile 20-like kinase 3 (MST3) mediates oxidative-stress-induced cell death by modulating JNK activation. Biosci Rep 2009; 29:405-15. [PMID: 19604147 DOI: 10.1042/bsr20090096] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
MST3 (mammalian sterile 20-like kinase 3) is a sterile 20 kinase reported to have a role in Fas-ligation- and staurosporine-induced cell death by unknown mechanism(s). We found that MST3-deficient cells are resistant to H2O2, which was reversed by reconstituting recombinant MST3. H2O2-induced JNK (c-Jun N-terminal kinase) activation was greatly enhanced in shMST3 cells (a cell line treated with short hairpin RNA against MST3). Suppression of JNK activity by the inhibitor SP600125 or by dominant-negative JNK2 re-sensitized cells to H2O2. Furthermore, c-Jun Ser-63 phosphorylation was augmented in shMST3 cells, whereas JunAA (dominant-negative c-Jun) reduced H2O2 resistance, implicating an AP-1 (activator protein 1) pathway in H2O2-induced survival signalling. Total cytoprotective HO-1 (haem oxygenase 1) expression, which was attenuated by JunAA, was induced up to 5-fold higher in shMST3 cells compared with controls. Zinc protoporphyrin IX, a potent inhibitor of HO reversed the H2O2-resistance of shMST3 cells. Our results reveal that H2O2-induced MST3-mediated cell death involves suppressing both a JNK survival pathway and up-regulation of HO-1.
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41
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Roovers K, Wagner S, Storbeck CJ, O'Reilly P, Lo V, Northey JJ, Chmielecki J, Muller WJ, Siegel PM, Sabourin LA. The Ste20-like kinase SLK is required for ErbB2-driven breast cancer cell motility. Oncogene 2009; 28:2839-48. [PMID: 19525980 DOI: 10.1038/onc.2009.146] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The Ste20-like kinase, SLK, is involved in the control of cell motility through its effects on actin reorganization and focal adhesion turnover. Here we investigated the role of SLK in chemotaxis downstream of the tyrosine kinase receptor, HER2/ErbB2/Neu, which is frequently overexpressed in human breast cancers. Our results show that SLK is required for the efficient cell migration of human and mouse mammary epithelial cell lines in the presence of the Neu activator, heregulin, as a chemoattractant. SLK activity is stimulated by heregulin treatment or by overexpression of activated Neu. Phosphorylation of tyrosine 1201 or tyrosines 1226/7 on Neu is a key event for SLK activation and cell migration, and cancer cell invasion mediated by these tyrosines is inhibited by kinase-inactive SLK. Signaling pathway inhibitors show that Neu-mediated SLK activation is dependent on MEK, PI3K, PLCgamma and Shc signaling. Furthermore, heregulin-stimulated SLK activity requires signals from the focal adhesion proteins, FAK and src. Finally, phospho-FAK analysis shows that SLK is required for Neu-dependent focal adhesion turnover. Together, these studies define an interaction between Neu and SLK signaling in the regulation of cancer cell motility.
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Affiliation(s)
- K Roovers
- Centre for Cancer Therapeutics, Ottawa Health Research Institute, Ontario, Canada
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42
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Delpire E. The mammalian family of sterile 20p-like protein kinases. Pflugers Arch 2009; 458:953-67. [PMID: 19399514 DOI: 10.1007/s00424-009-0674-y] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2009] [Accepted: 04/15/2009] [Indexed: 12/12/2022]
Abstract
Twenty-eight kinases found in mammalian genomes share similarity to the budding yeast kinase Ste20p. This review article examines the biological function of these mammalian Ste20 kinases. Some of them have conserved the Ste20p function of transducing extracellular signals to mitogen-activated kinases. Others affect ion transport, cell cycle, cytoskeleton organization, and program cell death. A number of molecular details involved in the activation of the kinases are discussed including autophosphorylation, substrate recognition, autoinhibition, dimerization, and substrate binding.
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Affiliation(s)
- Eric Delpire
- Department of Anesthesiology, Vanderbilt University Medical Center, T-4202 MCN 1161 21st Avenue South, Nashville, TN 37232-2520, USA.
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43
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Wagner SM, Sabourin LA. A novel role for the Ste20 kinase SLK in adhesion signaling and cell migration. Cell Adh Migr 2009; 3:182-4. [PMID: 19262175 DOI: 10.4161/cam.3.2.7229] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
With over 60 members, the Sterile 20 family of kinases has been implicated in numerous biological processes, including growth, survival, apoptosis and cell migration. Recently, we have shown that, in addition to cell death, the Ste20-like kinase SLK is required for efficient cell migration in fibroblasts. We have observed that SLK is involved in cell motility through its effect on actin reorganization and microtubule-induced focal adhesion turnover. Scratch wounding of confluent monolayers results in SLK activation. The induction of SLK kinase activity requires the scaffold FAK and a MAPK-dependent pathway. However, its recruitment to the leading edge of migrating fibroblasts requires the activity of the Src family kinases. Since SLK is microtubule-associated, it may represent one of the signals delivered to focal contacts that induces adhesions turnover. A speculative model is proposed to illustrate the mechanism of SLK activation and recruitment at the leading edge of migrating cells.
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Affiliation(s)
- Simona M Wagner
- Department of Cellular and Molecular Medicine, University of Ottawa and Cancer Therapeutics, Ottawa Health Research Institute, ON, CA.
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44
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Yan Y, Merlin D. Ste20-related proline/alanine-rich kinase: A novel regulator of intestinal inflammation. World J Gastroenterol 2008; 14:6115-21. [PMID: 18985800 PMCID: PMC2761571 DOI: 10.3748/wjg.14.6115] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Recently, inflammatory bowel disease (IBD) has been the subject of considerable research, with increasing attention being paid to the loss of intestinal epithelial cell barrier function as a mechanism of pathogenesis. Ste20-related proline/alanine-rich kinase (SPAK) is involved in regulating barrier function. SPAK is known to interact with inflammation-related kinases (such as p38, JNK, NKCC1, PKCtheta;, WNK and MLCK), and with transcription factor AP-1, resulting in diverse biological phenomena, including cell differentiation, cell transformation and proliferation, cytoskeleton rearrangement, and regulation of chloride transport. This review examines the involvement of Ste20-like kinases and downstream mitogen-activated protein kinases (MAPKs) pathways in the pathogenesis and control of intestinal inflammation. The primary focus will be on the molecular features of intestinal inflammation, with an emphasis on the interaction between SPAK and other molecules, and the effect of these interactions on homeostatic maintenance, cell volume regulation and increased cell permeability in intestinal inflammation.
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45
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Guilluy C, Rolli-Derkinderen M, Loufrani L, Bourgé A, Henrion D, Sabourin L, Loirand G, Pacaud P. Ste20-Related Kinase SLK Phosphorylates Ser188 of RhoA to Induce Vasodilation in Response to Angiotensin II Type 2 Receptor Activation. Circ Res 2008; 102:1265-74. [DOI: 10.1161/circresaha.107.164764] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The small G protein Rho signaling pathways are recognized as major regulators of cardiovascular functions, and activation of Rho proteins appears to be a common component for the pathogenesis of hypertension and vascular proliferative disorders. Recent evidence suggests that modulation of Rho protein signaling by phosphorylation of Rho proteins provides an additional simple mechanism for coordinating Rho protein functions. Phosphorylation of RhoA by cAMP- or cGMP-activated kinase on Ser188 induces cytosolic sequestration of RhoA through increased interaction with guanine dissociation inhibitor, thereby resulting in inhibition of RhoA-dependent functions. Here we show that stimulation of angiotensin II (Ang II) type 2 receptor (AT
2
R) in vascular smooth muscle cells induces Ser188 phosphorylation of RhoA independently of cAMP- or cGMP-activated kinase. We identify the Ser/Thr kinase Ste20-related kinase SLK as a new kinase phosphorylating RhoA on Ser188. Activation of the signaling cascade involving Src homology 2 domain–containing protein-tyrosine phosphatase 1, casein kinase II and SLK is responsible for RhoA phosphorylation and inhibition of RhoA-mediated arterial contraction induced by AT
2
R activation. These results thus identify the molecular mechanism linking AT
2
R to RhoA inhibition and vasodilation.
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Affiliation(s)
- Christophe Guilluy
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Malvyne Rolli-Derkinderen
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Laurent Loufrani
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Anne Bourgé
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Daniel Henrion
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Luc Sabourin
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Gervaise Loirand
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
| | - Pierre Pacaud
- From Inserm U915 (C.G., M.R.-D., A.B., G.L., P.P.); Faculté des Sciences, l’institut du thorax (C.G., M.R.-D., A.B., G.L., P.P.); Centre Hospitalier Universitaire Nantes, l’institut du thorax (G.L.), Nantes, France; Inserm U771 and Centre National de la Recherche Scientifique Unité Mixte de Recherche 6214 (L.L., D.H.), Faculté de Médecine Angers, France; University of Ottawa and Ottawa Health Research Institute (L.S.), Ontario, Canada
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Wagner S, Storbeck CJ, Roovers K, Chaar ZY, Kolodziej P, McKay M, Sabourin LA. FAK/src-family dependent activation of the Ste20-like kinase SLK is required for microtubule-dependent focal adhesion turnover and cell migration. PLoS One 2008; 3:e1868. [PMID: 18382658 PMCID: PMC2270904 DOI: 10.1371/journal.pone.0001868] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2007] [Accepted: 02/15/2008] [Indexed: 11/19/2022] Open
Abstract
Cell migration involves a multitude of signals that converge on cytoskeletal reorganization, essential for development, immune responses and tissue repair. Using knockdown and dominant negative approaches, we show that the microtubule-associated Ste20-like kinase SLK is required for focal adhesion turnover and cell migration downstream of the FAK/c-src complex. Our results show that SLK co-localizes with paxillin, Rac1 and the microtubules at the leading edge of migrating cells and is activated by scratch wounding. SLK activation is dependent on FAK/c-src/MAPK signaling, whereas SLK recruitment to the leading edge is src-dependent but FAK independent. Our results show that SLK represents a novel focal adhesion disassembly signal.
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Affiliation(s)
- Simona Wagner
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Chris J. Storbeck
- Cancer Therapeutics, Ottawa Health Research Institute, Ottawa, Ontario, Canada
| | - Kristin Roovers
- Cancer Therapeutics, Ottawa Health Research Institute, Ottawa, Ontario, Canada
| | - Ziad Y. Chaar
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Piotr Kolodziej
- Cancer Therapeutics, Ottawa Health Research Institute, Ottawa, Ontario, Canada
| | - Marlene McKay
- Cancer Therapeutics, Ottawa Health Research Institute, Ottawa, Ontario, Canada
| | - Luc A. Sabourin
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Cancer Therapeutics, Ottawa Health Research Institute, Ottawa, Ontario, Canada
- * E-mail:
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47
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Abstract
Mitogen-activated protein kinase (MAPK) cascades are central pathways that participate in the intracellular transmission of extracellular signals. Each of the MAPK signaling cascades seems to consist of three to five tiers of protein kinases that sequentially activate each other by phosphorylation. Since the majority of MAPK cascade components are kinases, the methods used to detect their activation involve determining phosphorylation state and protein kinase activities. The primary method describes the use of immunoblotting with specific anti-phospho antibody to detect activation of MAPK components. Alternative methods described are immunoprecipitation of desired protein kinases followed by phosphorylation of specific substrates and the use of an in-gel kinase assay. These methods have proven useful in the study of the MAPK signaling cascades.
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Affiliation(s)
- Yoav Shaul
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel
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48
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Burakov AV, Zhapparova ON, Kovalenko OV, Zinovkina LA, Potekhina ES, Shanina NA, Weiss DG, Kuznetsov SA, Nadezhdina ES. Ste20-related protein kinase LOSK (SLK) controls microtubule radial array in interphase. Mol Biol Cell 2008; 19:1952-61. [PMID: 18287541 DOI: 10.1091/mbc.e06-12-1156] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Interphase microtubules are organized into a radial array with centrosome in the center. This organization is a subject of cellular regulation that can be driven by protein phosphorylation. Only few protein kinases that regulate microtubule array in interphase cells have been described. Ste20-like protein kinase LOSK (SLK) was identified as a microtubule and centrosome-associated protein. In this study we have shown that the inhibition of LOSK activity by dominant-negative mutant K63R-DeltaT or by LOSK depletion with RNAi leads to unfocused microtubule arrangement. Microtubule disorganization is prominent in Vero, CV-1, and CHO-K1 cells but less distinct in HeLa cells. The effect is a result neither of microtubule stabilization nor of centrosome disruption. In cells with suppressed LOSK activity centrosomes are unable to anchor or to cap microtubules, though they keep nucleating microtubules. These centrosomes are depleted of dynactin. Vero cells overexpressing K63R-DeltaT have normal dynactin "comets" at microtubule ends and unaltered morphology of Golgi complex but are unable to polarize it at the wound edge. We conclude that protein kinase LOSK is required for radial microtubule organization and for the proper localization of Golgi complex in various cell types.
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Affiliation(s)
- Anton V Burakov
- Institute of Protein Research, Russian Academy of Science, 142290 Pushchino, Moscow Region, Russian Federation
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49
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Shaul Y, Seger R. The detection of MAPK signaling. CURRENT PROTOCOLS IN CELL BIOLOGY 2008; Chapter 14:Unit 14.3. [PMID: 18228462 DOI: 10.1002/0471143030.cb1403s28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Mitogen-activated protein kinase (MAPK) cascades are central pathways that participate in the intracellular transmission of extracellular signals. Each of the MAPK signaling cascades seems to consist of three to five tiers of protein kinases that sequentially activate each other by phosphorylation. Since the majority of MAPK cascade components are kinases, the methods used to detect their activation involve determining phosphorylation state and protein kinase activities. The Basic Protocol describes the use of immunoblotting with specific anti-phospho antibody to detect activation of MAPK components. Alternative methods described are immunoprecipitation of desired protein kinases followed by phosphorylation of specific substrates and the use of an in-gel kinase assay. These methods have proven useful in the study of the MAPK signaling cascades.
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Affiliation(s)
- Yoav Shaul
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel
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50
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Yan Y, Tulasne D, Browaeys E, Cailliau K, Khayath N, Pierce RJ, Trolet J, Fafeur V, Ben Younes A, Dissous C. Molecular cloning and characterisation of SmSLK, a novel Ste20-like kinase in Schistosoma mansoni. Int J Parasitol 2007; 37:1539-50. [PMID: 17651740 DOI: 10.1016/j.ijpara.2007.06.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 06/05/2007] [Accepted: 06/08/2007] [Indexed: 11/25/2022]
Abstract
Serine/threonine kinases of the Ste20 group play important roles in various cellular functions such as growth, apoptosis and morphogenesis. This family includes p21-Activated Kinases (PAKs) and Germinal Center Kinases (GCKs) families which contain their kinase domain in the C-terminal and N-terminal position, respectively. Here, we report the characterisation of a novel Ste20-like kinase (SLK) in the helminth parasite Schistosoma mansoni (SmSLK). SmSLK belongs to the GCK subfamily and contains a conserved N-terminal Ste20-like catalytic domain and C-terminal coiled-coil structures homologous to mammalian Lymphocyte Oriented Kinase (LOK) and SLK kinases and described as regulatory domains in these proteins. Gene assembly was performed using S. mansoni sequences available from genomic databases and indicated that SmSLK is composed of 18 exons and present in one copy in the S. mansoni genome. RT-PCR experiments demonstrated an alternative splicing of SmSLK in the exon 9 encoding the hinge region between kinase and coiled-coil domains of SmSLK and showed the expression of both transcript isoforms (SmSLK and SmSLK-S in which exon 9 is deleted) in all the S. mansoni parasite stages. Most of the Ste20-related proteins are active kinases known to regulate mitogen-activated protein kinase (MAPK) cascades. We demonstrated the kinase activity of SmSLK and SmSLK-S and their capacity to activate the MAPK/Jun N-terminal kinase (JNK) pathway in human embryonic kidney (HEK) cells as well as in Xenopus oocytes. Immunofluorescence studies indicated that SmSLK proteins were abundant in the tegument of adult schistosomes. Therefore, these results indicate that SmSLK is a new member of the GCK protein family that could participate in the regulation of MAPK cascade activation during host-parasite interactions.
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