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Hoellerbauer P, Kufeld M, Arora S, Mitchell K, Girard E, Herman J, Olson J, Paddison P. FBXO42 activity is required to prevent mitotic arrest, spindle assembly checkpoint activation and lethality in glioblastoma and other cancers. NAR Cancer 2024; 6:zcae021. [PMID: 38774470 PMCID: PMC11106029 DOI: 10.1093/narcan/zcae021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/23/2024] [Accepted: 05/15/2024] [Indexed: 05/24/2024] Open
Abstract
Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. To identify genes differentially required for the viability of GBM stem-like cells (GSCs), we performed functional genomic lethality screens comparing GSCs and control human neural stem cells. Among top-scoring hits in a subset of GBM cells was the F-box-containing gene FBXO42, which was also predicted to be essential in ∼15% of cell lines derived from a broad range of cancers. Mechanistic studies revealed that, in sensitive cells, FBXO42 activity prevents chromosome alignment defects, mitotic cell cycle arrest and cell death. The cell cycle arrest, but not the cell death, triggered by FBXO42 inactivation could be suppressed by brief exposure to a chemical inhibitor of Mps1, a key spindle assembly checkpoint (SAC) kinase. FBXO42's cancer-essential function requires its F-box and Kelch domains, which are necessary for FBXO42's substrate recognition and targeting by SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex. However, none of FBXO42's previously proposed targets, including ING4, p53 and RBPJ, were responsible for the observed phenotypes. Instead, our results suggest that FBOX42 alters the activity of one or more proteins that perturb chromosome-microtubule dynamics in cancer cells, which in turn leads to induction of the SAC and cell death.
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Affiliation(s)
- Pia Hoellerbauer
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, 98109 USA
| | - Megan Kufeld
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
| | - Sonali Arora
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
| | - Kelly Mitchell
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
| | - Emily J Girard
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, WA, 98101 USA
| | - Jacob A Herman
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
| | - James M Olson
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, WA, 98101 USA
| | - Patrick J Paddison
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, 98109 USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, 98109 USA
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2
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Hui X, Li L, Xiong W, Liu Y, Li H, Zhang H, Zhao S, Zhang Y. High PPP4C expression predicts poor prognosis in diffuse large B-cell lymphoma. Clin Exp Med 2024; 24:89. [PMID: 38683255 PMCID: PMC11058967 DOI: 10.1007/s10238-024-01356-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 04/15/2024] [Indexed: 05/01/2024]
Abstract
The significance of Protein phosphatase 4 catalytic subunit (PPP4C) in diffuse large B-cell lymphoma (DLBCL) prognosis is not well understood. This work aimed to investigate the expression of PPP4C in DLBCL, investigate the correlation between PPP4C expression and clinicopathological parameters, and assess the prognostic significance of PPP4C. The mRNA expression of PPP4C was investigated using data from TCGA and GEO. To further analyze PPP4C expression, immunohistochemistry was performed on tissue microarray samples. Correlation analysis between clinicopathological parameters and PPP4C expression was conducted using Pearson's chi-square test or Fisher's exact test. Univariate and multivariate Cox hazard models were utilized to determine the prognostic significance of clinicopathological features and PPP4C expression. Additionally, survival analysis was performed using Kaplan-Meier survival curves. In both TCGA and GEO datasets, we identified higher mRNA levels of PPP4C in tumor tissues compared to normal tissues. Upon analysis of various clinicopathological features of DLBCL, we observed a correlation between high PPP4C expression and ECOG score (P = 0.003). Furthermore, according to a Kaplan-Meier survival analysis, patients with DLBCL who exhibit high levels of PPP4C had worse overall survival (P = 0.001) and progression-free survival (P = 0.002). PPP4C was shown to be an independent predictive factor for OS and PFS in DLBCL by univariate and multivariate analysis (P = 0.011 and P = 0.040). This study's findings indicate that high expression of PPP4C is linked to a poor prognosis for DLBCL and may function as an independent prognostic factors.
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Affiliation(s)
- Xue Hui
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Liru Li
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Wenjing Xiong
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Yue Liu
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Hongbin Li
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Han Zhang
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China
| | - Shu Zhao
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China.
| | - Yue Zhang
- Department of Clinical Oncology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, 150040, China.
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3
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Réthi-Nagy Z, Ábrahám E, Sinka R, Juhász S, Lipinszki Z. Protein Phosphatase 4 Is Required for Centrobin Function in DNA Damage Repair. Cells 2023; 12:2219. [PMID: 37759442 PMCID: PMC10526779 DOI: 10.3390/cells12182219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/21/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Genome stability in human cells relies on the efficient repair of double-stranded DNA breaks, which is mainly achieved by homologous recombination (HR). Among the regulators of various cellular functions, Protein phosphatase 4 (PP4) plays a pivotal role in coordinating cellular response to DNA damage. Meanwhile, Centrobin (CNTRB), initially recognized for its association with centrosomal function and microtubule dynamics, has sparked interest due to its potential contribution to DNA repair processes. In this study, we investigate the involvement of PP4 and its interaction with CNTRB in HR-mediated DNA repair in human cells. Employing a range of experimental strategies, we investigate the physical interaction between PP4 and CNTRB and shed light on the importance of two specific motifs in CNTRB, the PP4-binding FRVP and the ATR kinase recognition SQ sequences, in the DNA repair process. Moreover, we examine cells depleted of PP4 or CNTRB and cells harboring FRVP and SQ mutations in CNTRB, which result in similar abnormal chromosome morphologies. This phenomenon likely results from the impaired resolution of Holliday junctions, which serve as crucial intermediates in HR. Taken together, our results provide new insights into the intricate mechanisms of PP4 and CNTRB-regulated HR repair and their interrelation.
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Affiliation(s)
- Zsuzsánna Réthi-Nagy
- MTA SZBK Lendület Laboratory of Cell Cycle Regulation, Institute of Biochemistry, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary; (Z.R.-N.); (E.Á.)
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, H-6726 Szeged, Hungary
| | - Edit Ábrahám
- MTA SZBK Lendület Laboratory of Cell Cycle Regulation, Institute of Biochemistry, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary; (Z.R.-N.); (E.Á.)
- National Laboratory for Biotechnology, Institute of Genetics, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary
| | - Rita Sinka
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
| | - Szilvia Juhász
- Institute of Biochemistry, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary
| | - Zoltán Lipinszki
- MTA SZBK Lendület Laboratory of Cell Cycle Regulation, Institute of Biochemistry, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary; (Z.R.-N.); (E.Á.)
- National Laboratory for Biotechnology, Institute of Genetics, HUN-REN Biological Research Centre, H-6726 Szeged, Hungary
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4
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Wang Q, Bode AM, Zhang T. Targeting CDK1 in cancer: mechanisms and implications. NPJ Precis Oncol 2023; 7:58. [PMID: 37311884 DOI: 10.1038/s41698-023-00407-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 05/25/2023] [Indexed: 06/15/2023] Open
Abstract
Cyclin dependent kinases (CDKs) are serine/threonine kinases that are proposed as promising candidate targets for cancer treatment. These proteins complexed with cyclins play a critical role in cell cycle progression. Most CDKs demonstrate substantially higher expression in cancer tissues compared with normal tissues and, according to the TCGA database, correlate with survival rate in multiple cancer types. Deregulation of CDK1 has been shown to be closely associated with tumorigenesis. CDK1 activation plays a critical role in a wide range of cancer types; and CDK1 phosphorylation of its many substrates greatly influences their function in tumorigenesis. Enrichment of CDK1 interacting proteins with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was conducted to demonstrate that the associated proteins participate in multiple oncogenic pathways. This abundance of evidence clearly supports CDK1 as a promising target for cancer therapy. A number of small molecules targeting CDK1 or multiple CDKs have been developed and evaluated in preclinical studies. Notably, some of these small molecules have also been subjected to human clinical trials. This review evaluates the mechanisms and implications of targeting CDK1 in tumorigenesis and cancer therapy.
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Affiliation(s)
- Qiushi Wang
- The Hormel Institute, University of Minnesota, 801 16th Ave NE, Austin, MN, 55912, USA
| | - Ann M Bode
- The Hormel Institute, University of Minnesota, 801 16th Ave NE, Austin, MN, 55912, USA.
| | - Tianshun Zhang
- The Hormel Institute, University of Minnesota, 801 16th Ave NE, Austin, MN, 55912, USA.
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5
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Saini LK, Bheri M, Pandey GK. Protein phosphatases and their targets: Comprehending the interactions in plant signaling pathways. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 134:307-370. [PMID: 36858740 DOI: 10.1016/bs.apcsb.2022.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Protein phosphorylation is a vital reversible post-translational modification. This process is established by two classes of enzymes: protein kinases and protein phosphatases. Protein kinases phosphorylate proteins while protein phosphatases dephosphorylate phosphorylated proteins, thus, functioning as 'critical regulators' in signaling pathways. The eukaryotic protein phosphatases are classified as phosphoprotein phosphatases (PPP), metallo-dependent protein phosphatases (PPM), protein tyrosine (Tyr) phosphatases (PTP), and aspartate (Asp)-dependent phosphatases. The PPP and PPM families are serine (Ser)/threonine (Thr) specific phosphatases (STPs) that dephosphorylate Ser and Thr residues. The PTP family dephosphorylates Tyr residues while dual-specificity phosphatases (DsPTPs/DSPs) dephosphorylate Ser, Thr, and Tyr residues. The composition of these enzymes as well as their substrate specificity are important determinants of their functional significance in a number of cellular processes and stress responses. Their role in animal systems is well-understood and characterized. The functional characterization of protein phosphatases has been extensively covered in plants, although the comprehension of their mechanistic basis is an ongoing pursuit. The nature of their interactions with other key players in the signaling process is vital to our understanding. The substrates or targets determine their potential as well as magnitude of the impact they have on signaling pathways. In this article, we exclusively overview the various substrates of protein phosphatases in plant signaling pathways, which are a critical determinant of the outcome of various developmental and stress stimuli.
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Affiliation(s)
- Lokesh K Saini
- Department of Plant Molecular Biology, University of Delhi South Campus, Dhaula Kuan, New Delhi, India
| | - Malathi Bheri
- Department of Plant Molecular Biology, University of Delhi South Campus, Dhaula Kuan, New Delhi, India
| | - Girdhar K Pandey
- Department of Plant Molecular Biology, University of Delhi South Campus, Dhaula Kuan, New Delhi, India.
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6
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Bezerra RP, Conniff AS, Uversky VN. Comparative study of structures and functional motifs in lectins from the commercially important photosynthetic microorganisms. Biochimie 2022; 201:63-74. [PMID: 35839918 DOI: 10.1016/j.biochi.2022.07.004] [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: 01/27/2022] [Revised: 06/17/2022] [Accepted: 07/08/2022] [Indexed: 11/26/2022]
Abstract
Photosynthetic microorganisms, specifically cyanobacteria and microalgae, can synthesize a vast array of biologically active molecules, such as lectins, that have great potential for various biotechnological and biomedical applications. However, since the structures of these proteins are not well established, likely due to the presence of intrinsically disordered regions, our ability to better understand their functionality is hampered. We embarked on a study of the carbohydrate recognition domain (CRD), intrinsically disordered regions (IDRs), amino acidic composition, as well as and functional motifs in lectins from cyanobacteria of the genus Arthrospira and microalgae Chlorella and Dunaliella genus using a combination of bioinformatics techniques. This search revealed the presence of five distinctive CRD types differently distributed between the genera. Most CRDs displayed a group-specific distribution, except to C. sorokiniana possessing distinctive CRD probably due to its specific lifestyle. We also found that all CRDs contain short IDRs. Bacterial lectin of Arthrospira prokarionte showed lower intrinsic disorder and proline content when compared to the lectins from the eukaryotic microalgae (Chlorella and Dunaliella). Among the important functions predicted in all lectins were several specific motifs, which directly interacts with proteins involved in the cell-cycle control and which may be used for pharmaceutical purposes. Since the aforementioned properties of each type of lectin were investigated in silico, they need experimental confirmation. The results of our study provide an overview of the distribution of CRD, IDRs, and functional motifs within lectin from the commercially important microalgae.
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Affiliation(s)
- Raquel P Bezerra
- Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco-UFRPE, Dom Manoel de Medeiros Ave, Recife, PE, 52171-900, Brazil.
| | - Amanda S Conniff
- Department of Medical Engineering, Morsani College of Medicine and College of Engineering, University of South Florida, Tampa, FL, 33612, USA.
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
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7
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UL34 Deletion Restricts Human Cytomegalovirus Capsid Formation and Maturation. Int J Mol Sci 2022; 23:ijms23105773. [PMID: 35628580 PMCID: PMC9143689 DOI: 10.3390/ijms23105773] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 02/01/2023] Open
Abstract
Over 50% of the world’s population is infected with Human Cytomegalovirus (HCMV). HCMV is responsible for serious complications in the immuno-compromised and is a leading cause of congenital birth defects. The molecular function of many HCMV proteins remains unknown, and a deeper understanding of the viral effectors that modulate virion maturation is required. In this study, we observed that UL34 is a viral protein expressed with leaky late kinetics that localises to the nucleus during infection. Deletion of UL34 from the HCMV genome (ΔUL34) did not abolish the spread of HCMV. Instead, over >100-fold fewer infectious virions were produced, so we report that UL34 is an augmenting gene. We found that ΔUL34 is dispensable for viral DNA replication, and its absence did not alter the expression of IE1, MCP, gB, UL26, UL83, or UL99 proteins. In addition, ΔUL34 infections were able to progress through the replication cycle to form a viral assembly compartment; however, virion maturation in the cytoplasm was abrogated. Further examination of the nucleus in ΔUL34 infections revealed replication compartments with aberrant morphology, containing significantly less assembled capsids, with almost none undergoing subsequent maturation. Therefore, this work lays the foundation for UL34 to be further investigated in the context of nuclear organization and capsid maturation during HCMV infection.
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8
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Dong MZ, Ouyang YC, Gao SC, Ma XS, Hou Y, Schatten H, Wang ZB, Sun QY. PPP4C facilitates homologous recombination DNA repair by dephosphorylating PLK1 during early embryo development. Development 2022; 149:dev200351. [PMID: 35546066 DOI: 10.1242/dev.200351] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 04/24/2022] [Indexed: 12/17/2023]
Abstract
Mammalian early embryo cells have complex DNA repair mechanisms to maintain genomic integrity, and homologous recombination (HR) plays the main role in response to double-strand DNA breaks (DSBs) in these cells. Polo-like kinase 1 (PLK1) participates in the HR process and its overexpression has been shown to occur in a variety of human cancers. Nevertheless, the regulatory mechanism of PLK1 remains poorly understood, especially during the S and G2 phase. Here, we show that protein phosphatase 4 catalytic subunit (PPP4C) deletion causes severe female subfertility due to accumulation of DNA damage in oocytes and early embryos. PPP4C dephosphorylated PLK1 at the S137 site, negatively regulating its activity in the DSB response in early embryonic cells. Depletion of PPP4C induced sustained activity of PLK1 when cells exhibited DNA lesions that inhibited CHK2 and upregulated the activation of CDK1, resulting in inefficient loading of the essential HR factor RAD51. On the other hand, when inhibiting PLK1 in the S phase, DNA end resection was restricted. These results demonstrate that PPP4C orchestrates the switch between high-PLK1 and low-PLK1 periods, which couple the checkpoint to HR.
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Affiliation(s)
- Ming-Zhe Dong
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100101, China
| | - Ying-Chun Ouyang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shi-Cai Gao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100101, China
| | - Xue-Shan Ma
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi Hou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Heide Schatten
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Zhen-Bo Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100101, China
| | - Qing-Yuan Sun
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou 510317, China
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9
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Regulation of TLR4 signaling through the TRAF6/sNASP axis by reversible phosphorylation mediated by CK2 and PP4. Proc Natl Acad Sci U S A 2021; 118:2107044118. [PMID: 34789577 DOI: 10.1073/pnas.2107044118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2021] [Indexed: 02/06/2023] Open
Abstract
Recognition of invading pathogens by Toll-like receptors (TLRs) activates innate immunity through signaling pathways that involved multiple protein kinases and phosphatases. We previously demonstrated that somatic nuclear autoantigenic sperm protein (sNASP) binds to TNF receptor-associated factor 6 (TRAF6) in the resting state. Upon TLR4 activation, a signaling complex consisting of TRAF6, sNASP, interleukin (IL)-1 receptor-associated kinase 4, and casein kinase 2 (CK2) is formed. CK2 then phosphorylates sNASP to release phospho-sNASP (p-sNASP) from TRAF6, initiating downstream signaling pathways. Here, we showed that protein phosphatase 4 (PP4) is the specific sNASP phosphatase that negatively regulates TLR4-induced TRAF6 activation and its downstream signaling pathway. Mechanistically, PP4 is directly recruited by phosphorylated sNASP to dephosphorylate p-sNASP to terminate TRAF6 activation. Ectopic expression of PP4 specifically inhibited sNASP-dependent proinflammatory cytokine production and downstream signaling following bacterial lipopolysaccharide (LPS) treatment, whereas silencing PP4 had the opposite effect. Primary macrophages and mice infected with recombinant adenovirus carrying a gene encoding PP4 (Ad-PP4) showed significant reduction in IL-6 and TNF-α production. Survival of Ad-PP4-infected mice was markedly increased due to a better ability to clear bacteria in a sepsis model. These results indicate that the serine/threonine phosphatase PP4 functions as a negative regulator of innate immunity by regulating the binding of sNASP to TRAF6.
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Zhu L, Dai S, Lu D, Xu P, Chen L, Han Y, Zhong L, Chang L, Wu Q. Role of NDEL1 and VEGF/VEGFR-2 in Mouse Hippocampus After Status Epilepticus. ASN Neuro 2021; 12:1759091420926836. [PMID: 32423231 PMCID: PMC7238446 DOI: 10.1177/1759091420926836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Nuclear-distribution element-like 1 (NDEL1) is associated with the
proliferation and migration of neurons. Vascular endothelial growth
factor (VEGF) in combination with VEGF receptor-2 (VEGFR-2) regulates
the proliferation and migration of neurons. This study was performed
to explore undefined alterations in the expression levels of NDEL1 and
VEGF/VEGFR-2 within the hippocampus after status epilepticus (SE).
Following the creation of pilocarpine-induced epilepsy models using
adolescent male C57BL/6 mice, Western blotting and reverse
transcription quantitative polymerase chain reaction were applied to
assess the levels of NDEL1, VEGF, and VEGFR-2 expression in whole
hippocampi at 1, 2, 3, and 4 weeks post-SE, respectively.
Immunofluorescent labeling was also employed to detect the
colocalization of NDEL1 and VEGF in the hippocampus. Our results
indicated that NDEL1 and VEGF have similar patterns of upregulation
throughout the hippocampus. Upregulation of VEGFR-2 occurred only in
the early stages, and the expression decreased shortly afterward.
NDEL1 and VEGF were coexpressed in the cornu ammonis 3 pyramidal cell,
granular, and polymorph layers of the dentate gyrus in the
hippocampus. This study revealed that NDEL1, VEGF, and VEGFR-2 may
work together and are involved in the pathophysiology in the
hippocampus after SE.
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Affiliation(s)
- Lin Zhu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Shujuan Dai
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Di Lu
- Biomedicine Engineering Research Centre, Kunming Medical University
| | - Puying Xu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Lu Chen
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Yanbing Han
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Lianmei Zhong
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Lvhua Chang
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
| | - Qian Wu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University
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11
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Park J, Lee DH. Functional roles of protein phosphatase 4 in multiple aspects of cellular physiology: a friend and a foe. BMB Rep 2021. [PMID: 32192570 PMCID: PMC7196183 DOI: 10.5483/bmbrep.2020.53.4.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protein phosphatase 4 (PP4), one of serine/threonine phosphatases, is involved in many critical cellular pathways, including DNA damage response (DNA repair, cell cycle regulation, and apoptosis), tumorigenesis, cell migration, immune response, stem cell development, glucose metabolism, and diabetes. PP4 has been steadily studied over the past decade about wide spectrum of physiological activities in cells. Given the many vital functions in cells, PP4 has great potential to develop into the finding of key working mechanisms and effective treatments for related diseases such as cancer and diabetes. In this review, we provide an overview of the cellular and molecular mechanisms by which PP4 impacts and also discuss the functional significance of it in cell health.
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Affiliation(s)
- Jaehong Park
- School of Biological Sciences and Biotechnology Graduate School, Chonnam National University, Gwangju 61186, Korea
| | - Dong-Hyun Lee
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju 61186; Research Center of Ecomimetics, Chonnam National University, Gwangju 61186, Korea
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12
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Karman Z, Rethi-Nagy Z, Abraham E, Fabri-Ordogh L, Csonka A, Vilmos P, Debski J, Dadlez M, Glover DM, Lipinszki Z. Novel perspectives of target-binding by the evolutionarily conserved PP4 phosphatase. Open Biol 2020; 10:200343. [PMID: 33352067 PMCID: PMC7776573 DOI: 10.1098/rsob.200343] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/27/2020] [Indexed: 02/06/2023] Open
Abstract
Protein phosphatase 4 (PP4) is an evolutionarily conserved and essential Ser/Thr phosphatase that regulates cell division, development and DNA repair in eukaryotes. The major form of PP4, present from yeast to human, is the PP4c-R2-R3 heterotrimeric complex. The R3 subunit is responsible for substrate-recognition via its EVH1 domain. In typical EVH1 domains, conserved phenylalanine, tyrosine and tryptophan residues form the specific recognition site for their target's proline-rich sequences. Here, we identify novel binding partners of the EVH1 domain of the Drosophila R3 subunit, Falafel, and demonstrate that instead of binding to proline-rich sequences this EVH1 variant specifically recognizes atypical ligands, namely the FxxP and MxPP short linear consensus motifs. This interaction is dependent on an exclusively conserved leucine that replaces the phenylalanine invariant of all canonical EVH1 domains. We propose that the EVH1 domain of PP4 represents a new class of the EVH1 family that can accommodate low proline content sequences, such as the FxxP motif. Finally, our data implicate the conserved Smk-1 domain of Falafel in target-binding. These findings greatly enhance our understanding of the substrate-recognition mechanisms and function of PP4.
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Affiliation(s)
- Zoltan Karman
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, H‐6725, Hungary
| | - Zsuzsanna Rethi-Nagy
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, H‐6725, Hungary
| | - Edit Abraham
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
| | - Lilla Fabri-Ordogh
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
| | - Akos Csonka
- Department of Traumatology, University of Szeged, Szeged, H‐6725, Hungary
| | - Peter Vilmos
- Biological Research Centre, Institute of Genetics, Szeged, H‐6726, Hungary
| | - Janusz Debski
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Michal Dadlez
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - David M. Glover
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- California Institute of Technology, Pasadena, CA 91125, USA
| | - Zoltan Lipinszki
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
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13
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Yusuff T, Jensen M, Yennawar S, Pizzo L, Karthikeyan S, Gould DJ, Sarker A, Gedvilaite E, Matsui Y, Iyer J, Lai ZC, Girirajan S. Drosophila models of pathogenic copy-number variant genes show global and non-neuronal defects during development. PLoS Genet 2020; 16:e1008792. [PMID: 32579612 PMCID: PMC7313740 DOI: 10.1371/journal.pgen.1008792] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 04/23/2020] [Indexed: 11/25/2022] Open
Abstract
While rare pathogenic copy-number variants (CNVs) are associated with both neuronal and non-neuronal phenotypes, functional studies evaluating these regions have focused on the molecular basis of neuronal defects. We report a systematic functional analysis of non-neuronal defects for homologs of 59 genes within ten pathogenic CNVs and 20 neurodevelopmental genes in Drosophila melanogaster. Using wing-specific knockdown of 136 RNA interference lines, we identified qualitative and quantitative phenotypes in 72/79 homologs, including 21 lines with severe wing defects and six lines with lethality. In fact, we found that 10/31 homologs of CNV genes also showed complete or partial lethality at larval or pupal stages with ubiquitous knockdown. Comparisons between eye and wing-specific knockdown of 37/45 homologs showed both neuronal and non-neuronal defects, but with no correlation in the severity of defects. We further observed disruptions in cell proliferation and apoptosis in larval wing discs for 23/27 homologs, and altered Wnt, Hedgehog and Notch signaling for 9/14 homologs, including AATF/Aatf, PPP4C/Pp4-19C, and KIF11/Klp61F. These findings were further supported by tissue-specific differences in expression patterns of human CNV genes, as well as connectivity of CNV genes to signaling pathway genes in brain, heart and kidney-specific networks. Our findings suggest that multiple genes within each CNV differentially affect both global and tissue-specific developmental processes within conserved pathways, and that their roles are not restricted to neuronal functions. Rare copy-number variants (CNVs), or large deletions and duplications in the genome, are associated with both neuronal and non-neuronal clinical features. Previous functional studies for these disorders have primarily focused on understanding the cellular mechanisms for neurological and behavioral phenotypes. To understand how genes within these CNVs contribute to developmental defects in non-neuronal tissues, we assessed 79 homologs of CNV and known neurodevelopmental genes in Drosophila models. We found that most homologs showed developmental defects when knocked down in the adult fly wing, ranging from mild size changes to severe wrinkled wings or lethality. Although a majority of tested homologs showed defects when knocked down specifically in wings or eyes, we found no correlation in the severity of the observed defects in these two tissues. A subset of the homologs showed disruptions in cellular processes in the developing fly wing, including alterations in cell proliferation, apoptosis, and cellular signaling pathways. Furthermore, human CNV genes also showed differences in gene expression patterns and interactions with signaling pathway genes across multiple human tissues. Our findings suggest that genes within CNV disorders affect global developmental processes in both neuronal and non-neuronal tissues.
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Affiliation(s)
- Tanzeen Yusuff
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Matthew Jensen
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Sneha Yennawar
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Lucilla Pizzo
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Siddharth Karthikeyan
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Dagny J. Gould
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Avik Sarker
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Erika Gedvilaite
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Yurika Matsui
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Janani Iyer
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Zhi-Chun Lai
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Santhosh Girirajan
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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14
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Scheidt T, Alka O, Gonczarowska-Jorge H, Gruber W, Rathje F, Dell’Aica M, Rurik M, Kohlbacher O, Zahedi RP, Aberger F, Huber CG. Phosphoproteomics of short-term hedgehog signaling in human medulloblastoma cells. Cell Commun Signal 2020; 18:99. [PMID: 32576205 PMCID: PMC7310537 DOI: 10.1186/s12964-020-00591-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 05/05/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Aberrant hedgehog (HH) signaling is implicated in the development of various cancer entities such as medulloblastoma. Activation of GLI transcription factors was revealed as the driving force upon pathway activation. Increased phosphorylation of essential effectors such as Smoothened (SMO) and GLI proteins by kinases including Protein Kinase A, Casein Kinase 1, and Glycogen Synthase Kinase 3 β controls effector activity, stability and processing. However, a deeper and more comprehensive understanding of phosphorylation in the signal transduction remains unclear, particularly during early response processes involved in SMO activation and preceding GLI target gene regulation. METHODS We applied temporal quantitative phosphoproteomics to reveal phosphorylation dynamics underlying the short-term chemical activation and inhibition of early hedgehog signaling in HH responsive human medulloblastoma cells. Medulloblastoma cells were treated for 5.0 and 15 min with Smoothened Agonist (SAG) to induce and with vismodegib to inhibit the HH pathway. RESULTS Our phosphoproteomic profiling resulted in the quantification of 7700 and 10,000 phosphosites after 5.0 and 15 min treatment, respectively. The data suggest a central role of phosphorylation in the regulation of ciliary assembly, trafficking, and signal transduction already after 5.0 min treatment. ERK/MAPK signaling, besides Protein Kinase A signaling and mTOR signaling, were differentially regulated after short-term treatment. Activation of Polo-like Kinase 1 and inhibition of Casein Kinase 2A1 were characteristic for vismodegib treatment, while SAG treatment induced Aurora Kinase A activity. Distinctive phosphorylation of central players of HH signaling such as SMO, SUFU, GLI2 and GLI3 was observed only after 15 min treatment. CONCLUSIONS This study provides evidence that phosphorylation triggered in response to SMO modulation dictates the localization of hedgehog pathway components within the primary cilium and affects the regulation of the SMO-SUFU-GLI axis. The data are relevant for the development of targeted therapies of HH-associated cancers including sonic HH-type medulloblastoma. A deeper understanding of the mechanisms of action of SMO inhibitors such as vismodegib may lead to the development of compounds causing fewer adverse effects and lower frequencies of drug resistance. Video Abstract.
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Affiliation(s)
- Tamara Scheidt
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | - Oliver Alka
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Humberto Gonczarowska-Jorge
- Leibniz-Institute of Analytical Sciences- ISAS - e.V, Dortmund, Germany
- Present address: CAPES Foundation, Ministry of Education of Brazil, Brasília, DF 70040-020 Brazil
| | - Wolfgang Gruber
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
- Present address: EVER Valinject GmbH, 4866 Unterach am Attersee, Austria
| | - Florian Rathje
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | | | - Marc Rurik
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Oliver Kohlbacher
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
- Biomolecular Interactions, Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076 Tübingen, Germany
- Institute for Translational Bioinformatics, University Hospital Tübingen, Hoppe-Seyler-Str. 9, 72076 Tübingen, Germany
- Applied Bioinformatics, Center for Bioinformatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - René P. Zahedi
- Leibniz-Institute of Analytical Sciences- ISAS - e.V, Dortmund, Germany
- Gerald Bronfman Department of Oncology, Jewish General Hospital, McGill University, Montreal, Canada
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Canada
| | - Fritz Aberger
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
| | - Christian G. Huber
- Department of Biosciences, Bioanalytical Research Laboratories and Molecular Cancer Research and Tumor Immunology, Cancer Cluster Salzburg, University of Salzburg, Hellbrunner Straße 34, 5020 Salzburg, Austria
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15
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Wang B, Zhu XX, Pan LY, Chen HF, Shen XY. PP4C facilitates lung cancer proliferation and inhibits apoptosis via activating MAPK/ERK pathway. Pathol Res Pract 2020; 216:152910. [PMID: 32139257 DOI: 10.1016/j.prp.2020.152910] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/09/2020] [Accepted: 02/28/2020] [Indexed: 12/26/2022]
Abstract
PURPOSE Protein phosphatase 4 catalytic subunit (PP4C) has been shown to play crucial regulatory roles in biological process and is frequently upregulated in cancer such as breast and colorectal carcinoma. However, the function and potential molecular mechanism of PP4C in lung cancer remains unclear. METHODS Bioinformatic analysis was used to detect the expression level and prognosis of patients. Western blot, quantitative real-time PCR (qRT-PCR), CCK8, 5-Ethynyl-2'-deoxyuridine (Edu) proliferation assay and flow cytometric were used to explore the function in lung cancer cells. RESULTS In this study, we found that PP4C was upregulated in lung cancer tissues as compared with that in normal lung tissues. Furthermore, patients with high expression level of PP4C were correlated with a poor prognosis in lung cancer patients. In vitro, CCK8, Edu proliferation assays and flow cytometry analysis showed that PP4C could promote lung cancer cell growth and inhibit apoptosis. Mechanistic investigations revealed that PP4C may interact with PP4R1 and promote ERK activation. Additionally, PP4C depletion resulted in lower tumor growth in vivo. CONCLUSIONS Taken together, these data showed the oncogenic of PP4C in NSCLC tumorigenesis and provide a new insight of PP4C in the progression of NSCLC.
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Affiliation(s)
- Bin Wang
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, No. 221 West Yan-an Road, Shanghai 200040, China
| | - Xun-Xia Zhu
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, No. 221 West Yan-an Road, Shanghai 200040, China
| | - Lin-Yue Pan
- Department of Respiration, The Affiliated Huadong Hospital of Fudan University, No. 221 West Yan-an Road, Shanghai 200040, China
| | - He-Feng Chen
- Department of Respiration, The Affiliated Huadong Hospital of Fudan University, No. 221 West Yan-an Road, Shanghai 200040, China.
| | - Xiao-Yong Shen
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, No. 221 West Yan-an Road, Shanghai 200040, China.
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16
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Wang B, Pan LY, Kang N, Shen XY. PP4R1 interacts with HMGA2 to promote non-small-cell lung cancer migration and metastasis via activating MAPK/ERK-induced epithelial-mesenchymal transition. Mol Carcinog 2020; 59:467-477. [PMID: 32077156 DOI: 10.1002/mc.23168] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/26/2020] [Accepted: 02/06/2020] [Indexed: 12/21/2022]
Abstract
Protein phosphatase 4 regulatory subunit 1 (PP4R1) has been shown to play a role in the regulation of centrosome maturation, apoptosis, DNA repair, and tumor necrosis factor signaling. However, the function of PP4R1 in non-small-cell lung cancer remains unclear. In this study, we identify PP4R1 as an oncogene through Oncomine database mining and immunohistochemical staining, and we showed that PP4R1 is upregulated in lung cancer tissues as compared with that in normal lung tissues and correlated with a poor prognosis in lung cancer patients. Furthermore, in vitro study by wound-healing and Transwell assay showed that PP4R1 could promote migration and invasion of lung cancer cells. Mechanistic investigations revealed that PP4R1 could cooperate with high mobility group AT-hook 2 and thereby promotes epithelial-mesenchymal transition via MAPK/extracellular receptor kinase activation. Taken together, our study provides a rich resource for understanding PP4R1 in lung cancer and indicates that PP4R1 may serve as a potential biomarker in lung cancer therapies.
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Affiliation(s)
- Bin Wang
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, Shanghai, China
| | - Lin-Yue Pan
- Department of Respiration, The Affiliated Huadong Hospital of Fudan University, Shanghai, China
| | - Ning Kang
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, Shanghai, China
| | - Xiao-Yong Shen
- Department of Thoracic Surgery, The Affiliated Huadong Hospital of Fudan University, Shanghai, China
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17
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Fujita I, Shitamukai A, Kusumoto F, Mase S, Suetsugu T, Omori A, Kato K, Abe T, Shioi G, Konno D, Matsuzaki F. Endfoot regeneration restricts radial glial state and prevents translocation into the outer subventricular zone in early mammalian brain development. Nat Cell Biol 2019; 22:26-37. [PMID: 31871317 DOI: 10.1038/s41556-019-0436-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 11/15/2019] [Indexed: 01/19/2023]
Abstract
Neural stem cells, called radial glia, maintain epithelial structure during the early neocortical development. The prevailing view claims that when radial glia first proliferate, their symmetric divisions require strict spindle orientation; its perturbation causes precocious neurogenesis and apoptosis. Here, we show that despite this conventional view, radial glia at the proliferative stage undergo normal symmetric divisions by regenerating an apical endfoot even if it is lost by oblique divisions. We found that the Notch-R-Ras-integrin β1 pathway promotes the regeneration of endfeet, whose leading edge bears ectopic adherens junctions and the Par-polarity complex. However, this regeneration ability gradually declines during the subsequent neurogenic stage and hence oblique divisions induce basal translocation of radial glia to form the outer subventricular zone, a hallmark of the development of the convoluted brain. Our study reveals that endfoot regeneration is a temporally changing cryptic property, which controls the radial glial state and its shift is essential for mammalian brain size expansion.
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Affiliation(s)
- Ikumi Fujita
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Atsunori Shitamukai
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Fumiya Kusumoto
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.,Laboratory of Molecular Cell Biology and Development, Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Shun Mase
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.,Laboratory of Molecular Cell Biology and Development, Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Taeko Suetsugu
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Ayaka Omori
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Kagayaki Kato
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Tokyo, Japan
| | - Takaya Abe
- Laboratory for Animal Resource Development, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.,Laboratory of Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Go Shioi
- Laboratory of Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Daijiro Konno
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.,Division of Pathophysiology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Fumio Matsuzaki
- Laboratory for Cell Asymmetry, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan. .,Laboratory of Molecular Cell Biology and Development, Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
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18
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Lei WL, Han F, Hu MW, Liang QX, Meng TG, Zhou Q, Ouyang YC, Hou Y, Schatten H, Wang ZB, Sun QY. Protein phosphatase 6 is a key factor regulating spermatogenesis. Cell Death Differ 2019; 27:1952-1964. [PMID: 31819157 DOI: 10.1038/s41418-019-0472-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 11/27/2019] [Indexed: 12/29/2022] Open
Abstract
Protein phosphatase 6 (PP6) is a member of the PP2A-like subfamily, which plays a critical role in many fundamental cellular processes. We recently reported that PP6 is essential for female fertility. Here, we report that PP6 is involved in meiotic recombination and that germ cell-specific deletion of PP6 by Stra8-Cre causes defective spermatogenesis. The PP6-deficient spermatocytes were arrested at the pachytene stage and defects in DSB repair and crossover formation were observed, indicating that PP6 facilitated meiotic double-stranded breaks (DSB) repair. Further investigations revealed that depletion of PP6 in the germ cells affected chromatin relaxation, which was dependent on MAPK pathway activity, consequently preventing programmed DSB repair factors from being recruited to proper positions on the chromatin. Taken together, our results demonstrate that PP6 has an important role in meiotic recombination and male fertility.
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Affiliation(s)
- Wen-Long Lei
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Feng Han
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Key Laboratory for Major Obstetric Diseases of Guangdong Province, Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510150, China
| | - Meng-Wen Hu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qiu-Xia Liang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Department of Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen, Guangdong, 518036, China
| | - Tie-Gang Meng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Qian Zhou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Ying-Chun Ouyang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yi Hou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Heide Schatten
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, 65211, USA
| | - Zhen-Bo Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100101, China.
| | - Qing-Yuan Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100101, China.
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19
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A Consensus Binding Motif for the PP4 Protein Phosphatase. Mol Cell 2019; 76:953-964.e6. [PMID: 31585692 DOI: 10.1016/j.molcel.2019.08.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 07/08/2019] [Accepted: 08/28/2019] [Indexed: 12/18/2022]
Abstract
Dynamic protein phosphorylation constitutes a fundamental regulatory mechanism in all organisms. Phosphoprotein phosphatase 4 (PP4) is a conserved and essential nuclear serine and threonine phosphatase. Despite the importance of PP4, general principles of substrate selection are unknown, hampering the study of signal regulation by this phosphatase. Here, we identify and thoroughly characterize a general PP4 consensus-binding motif, the FxxP motif. X-ray crystallography studies reveal that FxxP motifs bind to a conserved pocket in the PP4 regulatory subunit PPP4R3. Systems-wide in silico searches integrated with proteomic analysis of PP4 interacting proteins allow us to identify numerous FxxP motifs in proteins controlling a range of fundamental cellular processes. We identify an FxxP motif in the cohesin release factor WAPL and show that this regulates WAPL phosphorylation status and is required for efficient cohesin release. Collectively our work uncovers basic principles of PP4 specificity with broad implications for understanding phosphorylation-mediated signaling in cells.
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20
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Park J, Lee J, Lee DH. Identification of Protein Phosphatase 4 Inhibitory Protein That Plays an Indispensable Role in DNA Damage Response. Mol Cells 2019; 42:546-556. [PMID: 31272138 PMCID: PMC6681864 DOI: 10.14348/molcells.2019.0014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 06/11/2019] [Accepted: 06/19/2019] [Indexed: 12/15/2022] Open
Abstract
Protein phosphatase 4 (PP4) is a crucial protein complex that plays an important role in DNA damage response (DDR), including DNA repair, cell cycle arrest and apoptosis. Despite the significance of PP4, the mechanism by which PP4 is regulated remains to be elucidated. Here, we identified a novel PP4 inhibitor, protein phosphatase 4 inhibitory protein (PP4IP) and elucidated its cellular functions. PP4IP-knockout cells were generated using the CRISPR/Cas9 system, and the phosphorylation status of PP4 substrates (H2AX, KAP1, and RPA2) was analyzed. Then we investigated that how PP4IP affects the cellular functions of PP4 by immunoprecipitation, immunofluorescence, and DNA double-strand break (DSB) repair assays. PP4IP interacts with PP4 complex, which is affected by DNA damage and cell cycle progression and decreases the dephosphorylational activity of PP4. Both overexpression and depletion of PP4IP impairs DSB repairs and sensitizes cells to genotoxic stress, suggesting timely inhibition of PP4 to be indispensable for cells in responding to DNA damage. Our results identify a novel inhibitor of PP4 that inhibits PP4-mediated cellular functions and establish the physiological importance of this regulation. In addition, PP4IP might be developed as potential therapeutic reagents for targeting tumors particularly with high level of PP4C expression.
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Affiliation(s)
- Jaehong Park
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju 61186,
Korea
| | - Jihye Lee
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju 61186,
Korea
| | - Dong-Hyun Lee
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju 61186,
Korea
- Research Center of Ecomimetics, Chonnam National University, Gwangju 61186,
Korea
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21
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Ramos F, Villoria MT, Alonso-Rodríguez E, Clemente-Blanco A. Role of protein phosphatases PP1, PP2A, PP4 and Cdc14 in the DNA damage response. Cell Stress 2019; 3:70-85. [PMID: 31225502 PMCID: PMC6551743 DOI: 10.15698/cst2019.03.178] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Maintenance of genome integrity is fundamental for cellular physiology. Our hereditary information encoded in the DNA is intrinsically susceptible to suffer variations, mostly due to the constant presence of endogenous and environmental genotoxic stresses. Genomic insults must be repaired to avoid loss or inappropriate transmission of the genetic information, a situation that could lead to the appearance of developmental anomalies and tumorigenesis. To safeguard our genome, cells have evolved a series of mechanisms collectively known as the DNA damage response (DDR). This surveillance system regulates multiple features of the cellular response, including the detection of the lesion, a transient cell cycle arrest and the restoration of the broken DNA molecule. While the role of multiple kinases in the DDR has been well documented over the last years, the intricate roles of protein dephosphorylation have only recently begun to be addressed. In this review, we have compiled recent information about the function of protein phosphatases PP1, PP2A, PP4 and Cdc14 in the DDR, focusing mainly on their capacity to regulate the DNA damage checkpoint and the repair mechanism encompassed in the restoration of a DNA lesion.
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Affiliation(s)
- Facundo Ramos
- Cell Cycle and Genome Stability Group. Institute of Functional Biology and Genomics (IBFG). Spanish National Research Council (CSIC), University of Salamanca (USAL), C/Zacarías González 2, Salamanca 37007, SPAIN
| | - María Teresa Villoria
- Cell Cycle and Genome Stability Group. Institute of Functional Biology and Genomics (IBFG). Spanish National Research Council (CSIC), University of Salamanca (USAL), C/Zacarías González 2, Salamanca 37007, SPAIN
| | - Esmeralda Alonso-Rodríguez
- Cell Cycle and Genome Stability Group. Institute of Functional Biology and Genomics (IBFG). Spanish National Research Council (CSIC), University of Salamanca (USAL), C/Zacarías González 2, Salamanca 37007, SPAIN
| | - Andrés Clemente-Blanco
- Cell Cycle and Genome Stability Group. Institute of Functional Biology and Genomics (IBFG). Spanish National Research Council (CSIC), University of Salamanca (USAL), C/Zacarías González 2, Salamanca 37007, SPAIN
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22
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Moura M, Conde C. Phosphatases in Mitosis: Roles and Regulation. Biomolecules 2019; 9:E55. [PMID: 30736436 PMCID: PMC6406801 DOI: 10.3390/biom9020055] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 02/07/2023] Open
Abstract
Mitosis requires extensive rearrangement of cellular architecture and of subcellular structures so that replicated chromosomes can bind correctly to spindle microtubules and segregate towards opposite poles. This process originates two new daughter nuclei with equal genetic content and relies on highly-dynamic and tightly regulated phosphorylation of numerous cell cycle proteins. A burst in protein phosphorylation orchestrated by several conserved kinases occurs as cells go into and progress through mitosis. The opposing dephosphorylation events are catalyzed by a small set of protein phosphatases, whose importance for the accuracy of mitosis is becoming increasingly appreciated. This review will focus on the established and emerging roles of mitotic phosphatases, describe their structural and biochemical properties, and discuss recent advances in understanding the regulation of phosphatase activity and function.
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Affiliation(s)
- Margarida Moura
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, 4050-313 Porto, Portugal.
| | - Carlos Conde
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
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23
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Abstract
Variably expressive copy-number variants (CNVs) are characterized by extensive phenotypic heterogeneity of neuropsychiatric phenotypes. Approaches to identify single causative genes for these phenotypes within each CNV have not been successful. Here, we posit using multiple lines of evidence, including pathogenicity metrics, functional assays of model organisms, and gene expression data, that multiple genes within each CNV region are likely responsible for the observed phenotypes. We propose that candidate genes within each region likely interact with each other through shared pathways to modulate the individual gene phenotypes, emphasizing the genetic complexity of CNV-associated neuropsychiatric features.
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Affiliation(s)
- Matthew Jensen
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Bioinformatics and Genomics Program, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Santhosh Girirajan
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Bioinformatics and Genomics Program, Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania, United States of America
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24
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Chen MY, Hsu WC, Hsu SC, Yang YS, Chuang TH, Lin WJ, Tan TH, Su YW. PP4 deficiency leads to DNA replication stress that impairs immunoglobulin class switch efficiency. Cell Death Differ 2018; 26:1221-1234. [PMID: 30237510 PMCID: PMC6748143 DOI: 10.1038/s41418-018-0199-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 07/30/2018] [Accepted: 08/27/2018] [Indexed: 01/02/2023] Open
Abstract
The serine/threonine phosphatase PP4 has been implicated in DNA damage repair and cell cycle regulation through its dephosphorylation of specific substrates. We previously showed that PP4 is required for mouse B cell development, germinal center (GC) formation and immunoglobulin (Ig) class switch recombination (CSR). Here, we investigate the mechanisms underlying this requirement and demonstrate that murine PP4-deficient B lymphocytes have a defect in cell proliferation. Strikingly, the DNA damage response pathway that involves ATM/p53 and is linked to cell cycle arrest and impaired cell survival is strongly induced in these mutant B cells. In response to LPS + IL-4, stimuli that trigger IgG1 production, these PP4-deficient B cells show inefficient phosphorylation of ATR, leading to reduced retention of γH2AX-NBS1 complexes at sites of DNA damage, and compromised switching to IgG1. However, beyond the cell proliferation phase, conditional deletion of PP4 under the control of AID/cre completely restores normal IgG1 production in mutant B cell cultures. In vivo, co-deletion of PP4 and p53 by AID/cre partially rescues switching to IgG1 in B cells of mice immunized with TNP-KLH. Our findings establish that PP4 is indispensable for preventing DNA replication stress that could interfere with CSR, thereby promoting antibody switching during the humoral immune response.
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Affiliation(s)
- Ming-Yu Chen
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan
| | - Wei-Chan Hsu
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan
| | - Shu-Ching Hsu
- National Institute of Infectious Diseases and Vaccinology, NHRI, Zhunan, Miaoli County, Taiwan.,Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Medical Research and Development, Chang Bing Show Chwan Memorial Hospital, Chang Hua, Taiwan
| | - Yu-Shao Yang
- National Institute of Infectious Diseases and Vaccinology, NHRI, Zhunan, Miaoli County, Taiwan
| | - Tsung-Hsien Chuang
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan
| | - Wen-Jye Lin
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan
| | - Tse-Hua Tan
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan.,Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Yu-Wen Su
- Immunology Research Center, National Health Research Institutes (NHRI), Zhunan, Miaoli County, Taiwan.
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25
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Abstract
Polymerase δ-interacting protein 2 (Poldip2) is a multifunctional protein originally described as a binding partner of the p50 subunit of DNA polymerase δ and proliferating cell nuclear antigen. In addition to its role in DNA replication and damage repair, Poldip2 has been implicated in mitochondrial function, extracellular matrix regulation, cell cycle progression, focal adhesion turnover, and cell migration. However, Poldip2 functions are incompletely understood. In this review, we discuss recent literature on Poldip2 tissue distribution, subcellular localization, and function. We also address the putative function of Poldip2 in cardiovascular disease, neurodegenerative conditions and in renal pathophysiology.
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26
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Herzig JK, Bullinger L, Tasdogan A, Zimmermann P, Schlegel M, Teleanu V, Weber D, Rücker FG, Paschka P, Dolnik A, Schneider E, Kuchenbauer F, Heidel FH, Buske C, Döhner H, Döhner K, Gaidzik VI. Protein phosphatase 4 regulatory subunit 2 (PPP4R2) is recurrently deleted in acute myeloid leukemia and required for efficient DNA double strand break repair. Oncotarget 2017; 8:95038-95053. [PMID: 29221109 PMCID: PMC5707003 DOI: 10.18632/oncotarget.21119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/03/2017] [Indexed: 11/25/2022] Open
Abstract
We have previously identified a recurrent deletion at chromosomal band 3p14.1-p13 in patients with acute myeloid leukemia (AML). Among eight protein-coding genes, this microdeletion affects the protein phosphatase 4 regulatory subunit 2 (PPP4R2), which plays an important role in DNA damage response (DDR). Investigation of mRNA expression during murine myelopoiesis determined that Ppp4r2 is higher expressed in more primitive hematopoietic cells. PPP4R2 expression in primary AML samples compared to healthy bone marrow was significantly lower, particularly in patients with 3p microdeletion or complex karyotype. To identify a functional role of PPP4R2 in hematopoiesis and leukemia, we genetically inactivated Ppp4r2 by RNAi in murine hematopoietic stem and progenitor cells and murine myeloid leukemia. Furthermore, we ectopically expressed PPP4R2 in a deficient human myeloid leukemic cell line. While PPP4R2 is involved in DDR of both hematopoietic and leukemic cells, our findings indicate that PPP4R2 deficiency impairs de-phosphorylation of phosphorylated key DDR proteins KRAB-domain associated protein 1 (pKAP1), histone variant H2AX (γH2AX), tumor protein P53 (pP53), and replication protein A2 (pRPA2). Potential impact of affected DNA repair processes in primary AML cases with regard to differential PPP4R2 expression or 3p microdeletion is also supported by our results obtained by gene expression profiling and whole exome sequencing. Impaired DDR and increased DNA damage by PPP4R2 suppression is one possible mechanism by which the 3p microdeletion may contribute to the pathogenesis of AML. Further studies are warranted to determine the potential benefit of inefficient DNA repair upon PPP4R2 deletion to the development of therapeutic agents.
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Affiliation(s)
- Julia K Herzig
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Lars Bullinger
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Alpaslan Tasdogan
- Institute of Immunology, Ulm University, Ulm, Germany.,Current/Present address: Children's Medical Center Research Institute, UT Southwestern, Dallas, TX, USA
| | - Philipp Zimmermann
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Martin Schlegel
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Veronica Teleanu
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Daniela Weber
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Frank G Rücker
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Peter Paschka
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Anna Dolnik
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Edith Schneider
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Florian Kuchenbauer
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Florian H Heidel
- Leibniz Institute on Aging-Fritz Lipmann Institute, Jena, Germany.,Innere Medizin II, Hämatologie und Onkologie, Universitätsklinikum Jena, Jena, Germany
| | - Christian Buske
- Institute of Experimental Cancer Research, University Hospital of Ulm, Ulm, Germany
| | - Hartmut Döhner
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Konstanze Döhner
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
| | - Verena I Gaidzik
- Department of Internal Medicine III, University Hospital of Ulm, Ulm, Germany
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27
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Bradshaw NJ, Hayashi MAF. NDE1 and NDEL1 from genes to (mal)functions: parallel but distinct roles impacting on neurodevelopmental disorders and psychiatric illness. Cell Mol Life Sci 2017; 74:1191-1210. [PMID: 27742926 PMCID: PMC11107680 DOI: 10.1007/s00018-016-2395-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/13/2016] [Accepted: 10/06/2016] [Indexed: 01/01/2023]
Abstract
NDE1 (Nuclear Distribution Element 1, also known as NudE) and NDEL1 (NDE-Like 1, also known as NudEL) are the mammalian homologues of the fungus nudE gene, with important and at least partially overlapping roles for brain development. While a large number of studies describe the various properties and functions of these proteins, many do not directly compare the similarities and differences between NDE1 and NDEL1. Although sharing a high degree structural similarity and multiple common cellular roles, each protein presents several distinct features that justify their parallel but also unique functions. Notably both proteins have key binding partners in dynein, LIS1 and DISC1, which impact on neurodevelopmental and psychiatric illnesses. Both are implicated in schizophrenia through genetic and functional evidence, with NDE1 also strongly implicated in microcephaly, as well as other neurodevelopmental and psychiatric conditions through copy number variation, while NDEL1 possesses an oligopeptidase activity with a unique potential as a biomarker in schizophrenia. In this review, we aim to give a comprehensive overview of the various cellular roles of these proteins in a "bottom-up" manner, from their biochemistry and protein-protein interactions on the molecular level, up to the consequences for neuronal differentiation, and ultimately to their importance for correct cortical development, with direct consequences for the pathophysiology of neurodevelopmental and mental illness.
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Affiliation(s)
- Nicholas J Bradshaw
- Department of Neuropathology, Heinrich Heine University, Düsseldorf, Germany.
| | - Mirian A F Hayashi
- Department of Pharmacology, Universidade Federal de São Paulo (UNIFESP/EPM), São Paulo, Brazil
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28
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Winfree LM, Speese SD, Logan MA. Protein phosphatase 4 coordinates glial membrane recruitment and phagocytic clearance of degenerating axons in Drosophila. Cell Death Dis 2017; 8:e2623. [PMID: 28230857 PMCID: PMC5386485 DOI: 10.1038/cddis.2017.40] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 12/15/2022]
Abstract
Neuronal damage induced by injury, stroke, or neurodegenerative disease elicits swift immune responses from glial cells, including altered gene expression, directed migration to injury sites, and glial clearance of damaged neurons through phagocytic engulfment. Collectively, these responses hinder further cellular damage, but the mechanisms that underlie these important protective glial reactions are still unclear. Here, we show that the evolutionarily conserved trimeric protein phosphatase 4 (PP4) serine/threonine phosphatase complex is a novel set of factors required for proper glial responses to nerve injury in the adult Drosophila brain. Glial-specific knockdown of PP4 results in reduced recruitment of glia to severed axons and delayed glial clearance of degenerating axonal debris. We show that PP4 functions downstream of the the glial engulfment receptor Draper to drive glial morphogenesis through the guanine nucleotide exchange factor SOS and the Rho GTPase Rac1, revealing that PP4 molecularly couples Draper to Rac1-mediated cytoskeletal remodeling to ensure glial infiltration of injury sites and timely removal of damaged neurons from the CNS.
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Affiliation(s)
- Lilly M Winfree
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Sean D Speese
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Mary A Logan
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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29
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Kuo TC, Li LW, Pan SH, Fang JM, Liu JH, Cheng TJ, Wang CJ, Hung PF, Chen HY, Hong TM, Hsu YL, Wong CH, Yang PC. Purine-Type Compounds Induce Microtubule Fragmentation and Lung Cancer Cell Death through Interaction with Katanin. J Med Chem 2016; 59:8521-34. [DOI: 10.1021/acs.jmedchem.6b00797] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ting-Chun Kuo
- Ph.D.
Program in Translational Medicine, National Taiwan University and Academia Sinica, Taipei, Taiwan
| | - Ling-Wei Li
- Department
of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Szu-Hua Pan
- Ph.D.
Program in Translational Medicine, National Taiwan University and Academia Sinica, Taipei, Taiwan
- Graduate
Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei 100, Taiwan
- Genome
and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei 106, Taiwan
| | - Jim-Min Fang
- Department
of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Jyung-Hurng Liu
- Department
of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan
- Institute
of Genomics and Bioinformatics, National Chung Hsing University, Taichung 402, Taiwan
- Agricultural
Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan
- Rong
Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung 402, Taiwan
| | - Ting-Jen Cheng
- Genomics
Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Chia-Jen Wang
- Department
of Internal Medicine, National Taiwan University College of Medicine, Taipei 100, Taiwan
- Institute
of Stem Cell and Translational Cancer Research, Chang Gung Memorial HospitalTaipei 105, Taiwan
| | - Pei-Fang Hung
- Department
of Internal Medicine, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Hsuan-Yu Chen
- Institute
of Statistical Science, Academia Sinica, Taipei 115, Taiwan
| | - Tse-Ming Hong
- Institute
of Clinical Medicine, National Cheng Kung University College of Medicine, Tainan 701, Taiwan
| | - Yuan-Ling Hsu
- Graduate
Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Chi-Huey Wong
- Genomics
Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Pan-Chyr Yang
- Institute
of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
- NTU
Center for Genomic Medicine, National Taiwan University, Taipei 100, Taiwan
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30
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Protein phosphatase 4 catalytic subunit is overexpressed in glioma and promotes glioma cell proliferation and invasion. Tumour Biol 2016; 37:11893-11901. [DOI: 10.1007/s13277-016-5054-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/01/2016] [Indexed: 10/22/2022] Open
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31
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Huang X, Liu J, Shen T, Meng X, Dou L, Lin Y, Li J. Protein phosphatase 4 plays dual roles during cell proliferation. Cell Prolif 2016; 49:219-35. [PMID: 27041735 DOI: 10.1111/cpr.12249] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 01/28/2016] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVES Protein phosphatase 4 (PP4) has been reported to be indispensable for cell proliferation and survival. Deletion of PP4 has been shown to induce abnormal and even lethal events in growth and development both in lower eukaryotes and in mammals. However, until now, effects of PP4 up-regulation have remained unclear. MATERIALS AND METHODS To test effects of PP4 on cell proliferation, cell cycle and morphology in HepG2 cells, it was down-regulated using PP4 siRNA or its activity was inhibited using PP4RL (a PP4 phosphatase-dead mutant) adenoviruses. Alternatively, PP4 was up-regulated using PP4 adenoviruses. Next, we used a functional proteomic approach to identify proteins that may interact with PP4. Furthermore, we performed rescue experiments to verify the possible mechanisms. RESULTS To our surprise, we found that both up-regulation and inhibition of PP4 inhibited cell proliferation. Unlike PP4 inhibition, PP4 up-regulation induced prominent arrest at the prometaphase/metaphase transition by causing defects in chromosome alignment and spindle assembly. Moreover, we identified scaffold attachment factor A (SAF-A) (an important protein required for kinetochore-microtubule attachment that participates in the prometaphase/metaphase transition), to be a novel protein that interacts with PP4, using a proteomic approach. Thus, mutual regulatory mechanisms exist between PP4 and SAF-A. Interactions between PP4 and SAF-A played a role in prometaphase/metaphase transition. CONCLUSIONS Our data demonstrate a novel regulatory mechanism involving PP4 in cell proliferation.
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Affiliation(s)
- Xiuqing Huang
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | - Jin Liu
- College of Life Sciences, Beijing Normal University, Beijing, 100875, China
| | - Tao Shen
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | - Xiangyu Meng
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | - Lin Dou
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | - Yajun Lin
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
| | - Jian Li
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, 100730, China
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32
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Ogoh H, Tanuma N, Matsui Y, Hayakawa N, Inagaki A, Sumiyoshi M, Momoi Y, Kishimoto A, Suzuki M, Sasaki N, Ohuchi T, Nomura M, Teruya Y, Yasuda K, Watanabe T, Shima H. The protein phosphatase 6 catalytic subunit (Ppp6c) is indispensable for proper post-implantation embryogenesis. Mech Dev 2016; 139:1-9. [DOI: 10.1016/j.mod.2016.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 01/28/2016] [Accepted: 02/05/2016] [Indexed: 10/22/2022]
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33
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Qi Y, Hu T, Li K, Ye R, Ye Z. Lentivirus-Mediated Short-Hairpin RNA Targeting Protein Phosphatase 4 Regulatory Subunit 1 Inhibits Growth in Breast Cancer. J Breast Cancer 2015; 18:218-24. [PMID: 26472971 PMCID: PMC4600685 DOI: 10.4048/jbc.2015.18.3.218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 08/11/2015] [Indexed: 02/07/2023] Open
Abstract
Purpose Protein phosphatase 4 regulatory subunit 1 (PP4R1), as an interaction partner of the catalytic serine/threonine-protein phosphatase 4 catalytic subunit has been shown to involve in cellular processes and nuclear factor κB signaling. However, the functions of PP4R1 in human breast cancers remain unclear. This study is designed to explore the effect of PP4R1 knockdown on the biological characteristics of breast cancer cells. Methods A lentivirus-mediated short hairpin RNA (shRNA) was designed to knockdown the expression of PP4R1 in ZR-75-30 breast cancer cells. The efficiency of lentivirus-mediated shRNA infection was determined using fluorescence microscopy to observe lentivirus-mediated green fluorescent protein expression and confirmed to be over 80%. PP4R1 expression in infected ZR-75-30 cells was detected by quantitative real-time polymerase chain reaction and western blot analysis. Cell proliferation and colony formation ability were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and colony formation assay, respectively. Flow cytometry was used to measure cell cycle progression and cell apoptosis. In addition, apoptosis makers, including poly-ADP-ribose polymerase (PARP) and caspase-3, were investigated in PP4R1-silenced ZR-75-30 cells by western blot assay. Results We successfully constructed lentivirus-mediated shRNA to target PP4R1 in ZR-75-30 cells. MTT assay and colony formation assay showed the loss of PP4R1 suppressed the proliferation of ZR-75-30 cells. Flow cytometry analysis indicated cell cycle arrest and increased cell apoptosis in PP4R1 knockdown cells. Further, the apoptosis response in cells depleted of PP4R1 was illustrated by downregulation of PARP and upregulation of caspase-3. Conclusion Our results suggest that PP4R1 could promote breast cancer cell proliferation and might play a vital role in breast cancer occurrence.
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Affiliation(s)
- Yuying Qi
- Department of Laboratory, The Affiliated Ningde Municipal Hospital of Fujian Medical University, Ningde, China
| | - Tinghui Hu
- Department of Oncological Surgery, The Affiliated Ningde Municipal Hospital of Fujian Medical University, Ningde, China
| | - Kai Li
- Department of Oncological Surgery, The Affiliated Ningde Municipal Hospital of Fujian Medical University, Ningde, China
| | - Renqing Ye
- Department of Laboratory, The Affiliated Ningde Municipal Hospital of Fujian Medical University, Ningde, China
| | - Zuodong Ye
- Department of Laboratory, The Affiliated Ningde Municipal Hospital of Fujian Medical University, Ningde, China
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34
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Han S, Park J, Lee DH. Protein DHX38 is a novel inhibitor of protein phosphatase 4. Anim Cells Syst (Seoul) 2015. [DOI: 10.1080/19768354.2015.1074106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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35
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Arsenault HE, Roy J, Mapa CE, Cyert MS, Benanti JA. Hcm1 integrates signals from Cdk1 and calcineurin to control cell proliferation. Mol Biol Cell 2015; 26:3570-7. [PMID: 26269584 PMCID: PMC4603928 DOI: 10.1091/mbc.e15-07-0469] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 08/06/2015] [Indexed: 11/23/2022] Open
Abstract
The transcription factor Hcm1 is a key regulator of chromosome segregation and genome stability. The phosphatase calcineurin directly inactivates Hcm1 in response to environmental stress, which inhibits proliferation. Hcm1 functions as a rheostat, whose phosphorylation state affects the rate of proliferation. Cyclin-dependent kinase (Cdk1) orchestrates progression through the cell cycle by coordinating the activities of cell-cycle regulators. Although phosphatases that oppose Cdk1 are likely to be necessary to establish dynamic phosphorylation, specific phosphatases that target most Cdk1 substrates have not been identified. In budding yeast, the transcription factor Hcm1 activates expression of genes that regulate chromosome segregation and is critical for maintaining genome stability. Previously we found that Hcm1 activity and degradation are stimulated by Cdk1 phosphorylation of distinct clusters of sites. Here we show that, upon exposure to environmental stress, the phosphatase calcineurin inhibits Hcm1 by specifically removing activating phosphorylations and that this regulation is important for cells to delay proliferation when they encounter stress. Our work identifies a mechanism by which proliferative signals from Cdk1 are removed in response to stress and suggests that Hcm1 functions as a rheostat that integrates stimulatory and inhibitory signals to control cell proliferation.
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Affiliation(s)
- Heather E Arsenault
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01520
| | - Jagoree Roy
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Claudine E Mapa
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01520
| | - Martha S Cyert
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Jennifer A Benanti
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01520
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36
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Wu G, Ma Z, Qian J, Liu B. PP4R1 accelerates cell growth and proliferation in HepG2 hepatocellular carcinoma. Onco Targets Ther 2015; 8:2067-74. [PMID: 26300649 PMCID: PMC4535559 DOI: 10.2147/ott.s77709] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Hepatocellular carcinoma (HCC), as the fifth most common cancer worldwide, has become the third leading cause of cancer-related deaths. It is reported that protein phosphatase 4 (PP4) is an essential protein for nucleation, growth, and stabilization of microtubules in centrosomes/spindle bodies during cell division. Besides, previous studies have identified protein phosphatase 4 regulatory subunit 1 (PP4R1) as a constitutive interaction partner of PP4 catalytic subunit PP4C. The PP4C-PP4R1 PP4 complex plays a role in dephosphorylation, regulation of histone acetylation, and NF-κB activation. However, little is known about the pathological functions of PP4R1 in human cancers. Thus, in order to investigate how PP4R1 functions in human HCC, two common hepatocarcinogenesis HCC cell lines HepG2 and SMMC-7721 were employed, transduced with recombinant lentivirus expressing PP4R1 short hairpin RNA. Compared with the controls, the cells treated with Lv-shPP4R1 showed a significant decrease in cell proliferation and colony formation. The results of flow cytometry showed that the knockdown of PP4R1 caused HepG2 cells arrest at G2/M phase in the cell cycle. Furthermore, the transduction of Lv-shPP4R1 into HepG2 cells led to the inactivation of two major mitogen-activated protein kinase signaling cascades: p38 and c-Jun N-terminal kinase (JNK), indicating that PP4R1 could promote cell proliferation, which might be regulated by p38 and c-Jun N-terminal kinase pathways. In a word, this study highlights the crucial role of PP4R1 in promoting HCC cell growth, which might elucidate the pathological mechanism of HCC.
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Affiliation(s)
- Gang Wu
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Zhenyu Ma
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Jianmin Qian
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Bin Liu
- Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
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37
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DBZ regulates cortical cell positioning and neurite development by sustaining the anterograde transport of Lis1 and DISC1 through control of Ndel1 dual-phosphorylation. J Neurosci 2015; 35:2942-58. [PMID: 25698733 DOI: 10.1523/jneurosci.5029-13.2015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Cell positioning and neuronal network formation are crucial for proper brain function. Disrupted-in-Schizophrenia 1 (DISC1) is anterogradely transported to the neurite tips, together with Lis1, and functions in neurite extension via suppression of GSK3β activity. Then, transported Lis1 is retrogradely transported and functions in cell migration. Here, we show that DISC1-binding zinc finger protein (DBZ), together with DISC1, regulates mouse cortical cell positioning and neurite development in vivo. DBZ hindered Ndel1 phosphorylation at threonine 219 and serine 251. DBZ depletion or expression of a double-phosphorylated mimetic form of Ndel1 impaired the transport of Lis1 and DISC1 to the neurite tips and hampered microtubule elongation. Moreover, application of DISC1 or a GSK3β inhibitor rescued the impairments caused by DBZ insufficiency or double-phosphorylated Ndel1 expression. We concluded that DBZ controls cell positioning and neurite development by interfering with Ndel1 from disproportionate phosphorylation, which is critical for appropriate anterograde transport of the DISC1-complex.
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Lipinszki Z, Lefevre S, Savoian MS, Singleton MR, Glover DM, Przewloka MR. Centromeric binding and activity of Protein Phosphatase 4. Nat Commun 2015; 6:5894. [PMID: 25562660 PMCID: PMC4354016 DOI: 10.1038/ncomms6894] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 11/18/2014] [Indexed: 02/02/2023] Open
Abstract
The cell division cycle requires tight coupling between protein phosphorylation and dephosphorylation. However, understanding the cell cycle roles of multimeric protein phosphatases has been limited by the lack of knowledge of how their diverse regulatory subunits target highly conserved catalytic subunits to their sites of action. Phosphoprotein phosphatase 4 (PP4) has been recently shown to participate in the regulation of cell cycle progression. We now find that the EVH1 domain of the regulatory subunit 3 of Drosophila PP4, Falafel (Flfl), directly interacts with the centromeric protein C (CENP-C). Unlike other EVH1 domains that interact with proline-rich ligands, the crystal structure of the Flfl amino-terminal EVH1 domain bound to a CENP-C peptide reveals a new target-recognition mode for the phosphatase subunit. We also show that binding of Flfl to CENP-C is required to bring PP4 activity to centromeres to maintain CENP-C and attached core kinetochore proteins at chromosomes during mitosis.
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Affiliation(s)
- Zoltan Lipinszki
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Stephane Lefevre
- Macromolecular Structure and Function Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, UK
| | - Matthew S. Savoian
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Martin R. Singleton
- Macromolecular Structure and Function Laboratory, Cancer Research UK, London Research Institute, London WC2A 3LY, UK
| | - David M. Glover
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Marcin R. Przewloka
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
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Corradini BR, Iamashita P, Tampellini E, Farfel JM, Grinberg LT, Moreira-Filho CA. Complex network-driven view of genomic mechanisms underlying Parkinson's disease: analyses in dorsal motor vagal nucleus, locus coeruleus, and substantia nigra. BIOMED RESEARCH INTERNATIONAL 2014; 2014:543673. [PMID: 25525598 PMCID: PMC4261556 DOI: 10.1155/2014/543673] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 09/15/2014] [Indexed: 12/16/2022]
Abstract
Parkinson's disease (PD)—classically characterized by severe loss of dopaminergic neurons in the substantia nigra pars compacta—has a caudal-rostral progression, beginning in the dorsal motor vagal nucleus and, in a less extent, in the olfactory system, progressing to the midbrain and eventually to the basal forebrain and the neocortex. About 90% of the cases are idiopathic. To study the molecular mechanisms involved in idiopathic PD we conducted a comparative study of transcriptional interaction networks in the dorsal motor vagal nucleus (VA), locus coeruleus (LC), and substantia nigra (SN) of idiopathic PD in Braak stages 4-5 (PD) and disease-free controls (CT) using postmortem samples. Gene coexpression networks (GCNs) for each brain region (patients and controls) were obtained to identify highly connected relevant genes (hubs) and densely interconnected gene sets (modules). GCN analyses showed differences in topology and module composition between CT and PD networks for each anatomic region. In CT networks, VA, LC, and SN hub modules are predominantly associated with neuroprotection and homeostasis in the ageing brain, whereas in the patient's group, for the three brain regions, hub modules are mostly related to stress response and neuron survival/degeneration mechanisms.
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Affiliation(s)
- Beatriz Raposo Corradini
- Department of Pediatrics, Faculdade de Medicina da USP (FMUSP), Avenida Dr. Enéas Carvalho Aguiar 647, 5 Andar, 05403-900 São Paulo, SP, Brazil
| | - Priscila Iamashita
- Department of Pediatrics, Faculdade de Medicina da USP (FMUSP), Avenida Dr. Enéas Carvalho Aguiar 647, 5 Andar, 05403-900 São Paulo, SP, Brazil
| | - Edilaine Tampellini
- Brazilian Aging Brain Study Group (BEHEEC), LIM 22, FMUSP, 01246-903 São Paulo, SP, Brazil
- Hospital Israelita Albert Einstein, 05652-900 São Paulo, SP, Brazil
| | - José Marcelo Farfel
- Hospital Israelita Albert Einstein, 05652-900 São Paulo, SP, Brazil
- Division of Geriatrics, FMUSP, 01246-903 São Paulo, SP, Brazil
| | - Lea Tenenholz Grinberg
- Brazilian Aging Brain Study Group (BEHEEC), LIM 22, FMUSP, 01246-903 São Paulo, SP, Brazil
- Department of Pathology, FMUSP, 01246-903 São Paulo, SP, Brazil
- Department of Neurology and Pathology, University of California, San Francisco, CA 94143, USA
| | - Carlos Alberto Moreira-Filho
- Department of Pediatrics, Faculdade de Medicina da USP (FMUSP), Avenida Dr. Enéas Carvalho Aguiar 647, 5 Andar, 05403-900 São Paulo, SP, Brazil
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Merkel cell polyomavirus small T antigen mediates microtubule destabilization to promote cell motility and migration. J Virol 2014; 89:35-47. [PMID: 25320307 PMCID: PMC4301106 DOI: 10.1128/jvi.02317-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
UNLABELLED Merkel cell carcinoma (MCC) is an aggressive skin cancer of neuroendocrine origin with a high propensity for recurrence and metastasis. Merkel cell polyomavirus (MCPyV) causes the majority of MCC cases due to the expression of the MCPyV small and large tumor antigens (ST and LT, respectively). Although a number of molecular mechanisms have been attributed to MCPyV tumor antigen-mediated cellular transformation or replication, to date, no studies have investigated any potential link between MCPyV T antigen expression and the highly metastatic nature of MCC. Here we use a quantitative proteomic approach to show that MCPyV ST promotes differential expression of cellular proteins implicated in microtubule-associated cytoskeletal organization and dynamics. Intriguingly, we demonstrate that MCPyV ST expression promotes microtubule destabilization, leading to a motile and migratory phenotype. We further highlight the essential role of the microtubule-associated protein stathmin in MCPyV ST-mediated microtubule destabilization and cell motility and implicate the cellular phosphatase catalytic subunit protein phosphatase 4C (PP4C) in the regulation of this process. These findings suggest a possible molecular mechanism for the highly metastatic phenotype associated with MCC. IMPORTANCE Merkel cell polyomavirus (MCPyV) causes the majority of cases of Merkel cell carcinoma (MCC), an aggressive skin cancer with a high metastatic potential. However, the molecular mechanisms leading to virally induced cancer development have yet to be fully elucidated. In particular, no studies have investigated any potential link between the virus and the highly metastatic nature of MCC. We demonstrate that the MCPyV small tumor antigen (ST) promotes the destabilization of the host cell microtubule network, which leads to a more motile and migratory cell phenotype. We further show that MCPyV ST induces this process by regulating the phosphorylation status of the cellular microtubule-associated protein stathmin by its known association with the cellular phosphatase catalytic subunit PP4C. These findings highlight stathmin as a possible biomarker of MCC and as a target for novel antitumoral therapies.
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Chen MY, Chen YP, Wu MS, Yu GY, Lin WJ, Tan TH, Su YW. PP4 is essential for germinal center formation and class switch recombination in mice. PLoS One 2014; 9:e107505. [PMID: 25215539 PMCID: PMC4162579 DOI: 10.1371/journal.pone.0107505] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/11/2014] [Indexed: 01/12/2023] Open
Abstract
PP4 is a serine/threonine phosphatase required for immunoglobulin (Ig) VDJ recombination and pro-B/pre-B cell development in mice. To elucidate the role of PP4 in mature B cells, we ablated the catalytic subunit of murine PP4 invivo utilizing the CD23 promoter and cre-loxP recombination and generated CD23crePP4F/F mice. The development of follicular and marginal zone B cells was unaffected in these mutants, but the proliferation of mature PP4-deficient B cells stimulated by invitro treatment with either anti-IgM antibody (Ab) or LPS was partially impaired. Interestingly, the induction of CD80 and CD86 expression on these stimulated B cells was normal. Basal levels of serum Igs of all isotypes were strongly reduced in CD23crePP4F/F mice, and their B cells showed a reduced efficiency of class switch recombination (CSR) invitro upon stimulation by LPS or LPS plus IL-4. When CD23crePP4F/F mice were challenged with either the T cell-dependent antigen TNP-KLH or the T cell-independent antigen TNP-Ficoll, or by H1N1 virus infection, the mutant animals failed to form germinal centers (GCs) in the spleen and the draining mediastinal lymph nodes, and did not efficiently mount antigen-specific humoral responses. In the resting state, PP4-deficient B cells exhibited pre-existing DNA fragmentation. Upon stimulation by DNA-damaging drug etoposide invitro, mutant B cells showed increased cleavage of caspase 3. In addition, the mutant B cells displayed impaired CD40-mediated MAPK activation, abnormal IgM-mediated NF-κB activation, and reduced S phase entry upon IgM/CD40-stimulation. Taken together, our results establish a novel role for PP4 in CSR, and reveal crucial functions for PP4 in the maintenance of genomic stability, GC formation, and B cell-mediated immune responses.
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Affiliation(s)
- Ming-Yu Chen
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Ya-Ping Chen
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Ming-Sian Wu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Guanni-Yi Yu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Wen-Jye Lin
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Tse-Hua Tan
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Yu-Wen Su
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
- * E-mail:
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Alvarez-Fernández M, Malumbres M. Preparing a cell for nuclear envelope breakdown: Spatio-temporal control of phosphorylation during mitotic entry. Bioessays 2014; 36:757-65. [PMID: 24889070 DOI: 10.1002/bies.201400040] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Chromosome segregation requires the ordered separation of the newly replicated chromosomes between the two daughter cells. In most cells, this requires nuclear envelope (NE) disassembly during mitotic entry and its reformation at mitotic exit. Nuclear envelope breakdown (NEB) results in the mixture of two cellular compartments. This process is controlled through phosphorylation of multiple targets by cyclin-dependent kinase 1 (Cdk1)-cyclin B complexes as well as other mitotic enzymes. Experimental evidence also suggests that nucleo-cytoplasmic transport of critical cell cycle regulators such as Cdk1-cyclin B complexes or Greatwall, a kinase responsible for the inactivation of PP2A phosphatases, plays a major role in maintaining the boost of mitotic phosphorylation thus preventing the potential mitotic collapse derived from NEB. These data suggest the relevance of nucleo-cytoplasmic transport not only to communicate cytoplasmic and nuclear compartments during interphase, but also to prepare cells for the mixture of these two compartments during mitosis.
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Bradshaw NJ, Hennah W, Soares DC. NDE1 and NDEL1: twin neurodevelopmental proteins with similar 'nature' but different 'nurture'. Biomol Concepts 2013; 4:447-64. [PMID: 24093049 PMCID: PMC3787581 DOI: 10.1515/bmc-2013-0023] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Nuclear distribution element 1 (NDE1, also known as NudE) and NDE-like 1 (NDEL1, also known as Nudel) are paralogous proteins essential for mitosis and neurodevelopment that have been implicated in psychiatric and neurodevelopmental disorders. The two proteins possess high sequence similarity and have been shown to physically interact with one another. Numerous lines of experimental evidence in vivo and in cell culture have demonstrated that these proteins share common functions, although instances of differing functions between the two have recently emerged. We review the key aspects of NDE1 and NDEL1 in terms of recent advances in structure elucidation and cellular function, with an emphasis on their differing mechanisms of post-translational modification. Based on a review of the literature and bioinformatics assessment, we advance the concept that the twin proteins NDE1 and NDEL1, while sharing a similar 'nature' in terms of their structure and basic functions, appear to be different in their 'nurture', the manner in which they are regulated both in terms of expression and of post-translational modification within the cell. These differences are likely to be of significant importance in understanding the specific roles of NDE1 and NDEL1 in neurodevelopment and disease.
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Affiliation(s)
- Nicholas J. Bradshaw
- Department of Neuropathology, Heinrich Heine University, Düsseldorf, University Medical School, Moorenstrasse 5, D-40225, Düsseldorf, Germany
| | - William Hennah
- Institute for Molecular Medicine Finland FIMM, University of Helsinki, Helsinki, Finland; and National Institute for, Health and Welfare, Department of Mental Health and Substance, Abuse Services, Helsinki, Finland
| | - Dinesh C. Soares
- MRC Institute of Genetics and Molecular Medicine (MRC IGMM), University of Edinburgh, Western General, Hospital, Crewe Road South, Edinburgh EH4 2XU, UK
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Li L, Sase A, Patil S, Sunyer B, Höger H, Smalla KH, Stork O, Lubec G. Distinct set of kinases induced after retrieval of spatial memory discriminate memory modulation processes in the mouse hippocampus. Hippocampus 2013; 23:672-83. [PMID: 23536525 DOI: 10.1002/hipo.22127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2013] [Indexed: 12/15/2022]
Abstract
Protein phosphorylation and dephosphorylation events play a key role in memory formation and various protein kinases and phosphatases have been firmly associated with memory performance. Here, we determined expression changes of protein kinases and phosphatases following retrieval of spatial memory in CD1 mice in a Morris Water Maze task, using antibody microarrays and confirmatory Western blot. Comparing changes following single and consecutive retrieval, we identified stably and differentially expressed kinases, some of which have never been implicated before in memory functions. On the basis of these findings we define a small signaling network associated with spatial memory retrieval. Moreover, we describe differential regulation and correlation of expression levels with behavioral performance of polo-like kinase 1. Together with its recently observed genetic association to autism-spectrum disorders our data suggest a role of this kinase in balancing preservation and flexibility of learned behavior.
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Affiliation(s)
- Lin Li
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
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45
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Abstract
In this issue of Neuron, Xie et al. (2013) identified protein phosphatase 4c (PP4c) as a new component in the regulation of spindle orientation during mammalian neurogenesis. Importantly, their findings uncovered a novel and critical temporal aspect of the regulation of spindle orientation during neurogenesis.
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Affiliation(s)
- Anthony Wynshaw-Boris
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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46
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Su YW, Chen YP, Chen MY, Reth M, Tan TH. The serine/threonine phosphatase PP4 is required for pro-B cell development through its promotion of immunoglobulin VDJ recombination. PLoS One 2013; 8:e68804. [PMID: 23874770 PMCID: PMC3712940 DOI: 10.1371/journal.pone.0068804] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/31/2013] [Indexed: 12/15/2022] Open
Abstract
PP4 phosphatase regulates a number of crucial processes but the role of PP4 in B cells has never been reported. We generated B cell-specific pp4 knockout mice and have identified an essential role for PP4 in B cell development. Deficiency of PP4 in B lineage cells leads to a strong reduction in pre-B cell numbers, an absence in immature B cells, and a complete loss of mature B cells. In PP4-deficient pro-B cells, immunoglobulin (Ig) DJ(H) recombination is impaired and Ig µ heavy chain expression is greatly decreased. In addition, PP4-deficient pro-B cells show an increase of DNA double-strand breaks at Ig loci. Consistent with their reduced numbers, residual PP4-deficient pre-B cells accumulate in the G1 phase, exhibit excessive DNA damage, and undergo increased apoptosis. Overexpression of transgenic Ig in PP4-deficient mice rescues the defect in B cell development such that the animals have normal numbers of IgM(+) B cells. Our study therefore reveals a novel function for PP4 in pro-B cell development through its promotion of V(H)DJ(H) recombination.
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Affiliation(s)
- Yu-Wen Su
- Immunology Research Center, National Health Research Institutes, Zhunan, Miaoli County, Taiwan.
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Xie Y, Jüschke C, Esk C, Hirotsune S, Knoblich JA. The phosphatase PP4c controls spindle orientation to maintain proliferative symmetric divisions in the developing neocortex. Neuron 2013; 79:254-65. [PMID: 23830831 PMCID: PMC3725415 DOI: 10.1016/j.neuron.2013.05.027] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2013] [Indexed: 12/28/2022]
Abstract
In the developing neocortex, progenitor cells expand through symmetric division before they generate cortical neurons through multiple rounds of asymmetric cell division. Here, we show that the orientation of the mitotic spindle plays a crucial role in regulating the transition between those two division modes. We demonstrate that the protein phosphatase PP4c regulates spindle orientation in early cortical progenitor cells. Upon removing PP4c, mitotic spindles fail to orient in parallel to the neuroepithelial surface and progenitors divide with random orientation. As a result, their divisions become asymmetric and neurogenesis starts prematurely. Biochemical and genetic experiments show that PP4c acts by dephosphorylating the microtubule binding protein Ndel1, thereby enabling complex formation with Lis1 to form a functional spindle orientation complex. Our results identify a key regulator of cortical development and demonstrate that changes in the orientation of progenitor division are responsible for the transition between symmetric and asymmetric cell division. PP4c is required for spindle orientation in cortical progenitors Loss of PP4c leads to premature neuronal differentiation Spindle misorientation causes layering defects during a critical time window PP4c acts on Ndel1 and Lis1
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Affiliation(s)
- Yunli Xie
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Dr. Bohr-Gasse 3-5, 1030 Vienna, Austria
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Theobald B, Bonness K, Musiyenko A, Andrews JF, Urban G, Huang X, Dean NM, Honkanen RE. Suppression of Ser/Thr phosphatase 4 (PP4C/PPP4C) mimics a novel post-mitotic action of fostriecin, producing mitotic slippage followed by tetraploid cell death. Mol Cancer Res 2013; 11:845-55. [PMID: 23671329 DOI: 10.1158/1541-7786.mcr-13-0032] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Fostriecin is a natural product purified from Sterptomyces extracts with antitumor activity sufficient to warrant human clinical trials. Unfortunately, difficulties associated with supply and stable drug formulation stalled further development. At a molecular level, fostriecin is known to act as a catalytic inhibitor of four PPP-family phosphatases, and reports describing the design of molecules in this class suggest derivatives targeting enzymes within the fostriecin-sensitive subfamily can be successful. However, it is not clear if the tumor-selective cytotoxicity of fostriecin results from the inhibition of a specific phosphatase, multiple phosphatases, or a limited subset of fostriecin sensitive phosphatases. How the inhibition of sensitive phosphatases contributes to tumor-selective cytotoxicity is also not clear. Here, high-content time-lapse imaging of live cells revealed novel insight into the cellular actions of fostriecin, showing that fostriecin-induced apoptosis is not simply induced following a sustained mitotic arrest. Rather, apoptosis occurred in an apparent second interphase produced when tetraploid cells undergo mitotic slippage. Comparison of the actions of fostriecin and antisense-oligonucleotides specifically targeting human fostriecin-sensitive phosphatases revealed that the suppression PP4C alone is sufficient to mimic many actions of fostriecin. Importantly, targeted suppression of PP4C induced apoptosis, with death occurring in tetraploid cells following mitotic slippage. This effect was not observed following the suppression of PP1C, PP2AC, or PP5C. These data clarify PP4C as a fostriecin-sensitive phosphatase and demonstrate that the suppression of PP4C triggers mitotic slippage/apoptosis. IMPLICATIONS Future development of fostriecin class inhibitors should consider PP4C as a potentially important target. Mol Cancer Res; 11(8); 845-55. ©2013 AACR.
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Affiliation(s)
- Benjamin Theobald
- Department of Biochemistry and Molecular Biology, MSB 2362, University of South Alabama, Mobile, AL 36688, USA
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Ghosh DK, Dasgupta D, Guha A. Models, Regulations, and Functions of Microtubule Severing by Katanin. ISRN MOLECULAR BIOLOGY 2012; 2012:596289. [PMID: 27335666 PMCID: PMC4890891 DOI: 10.5402/2012/596289] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 08/20/2012] [Indexed: 12/22/2022]
Abstract
Regulation of microtubule dynamics depends on stochastic balance between polymerization and severing process which lead to differential spatiotemporal abundance and distribution of microtubules during cell development, differentiation, and morphogenesis. Microtubule severing by a conserved AAA family protein Katanin has emerged as an important microtubule architecture modulating process in cellular functions like division, migration, shaping and so on. Regulated by several factors, Katanin manifests connective crosstalks in network motifs in regulation of anisotropic severing pattern of microtubule protofilaments in cell type and stage dependent way. Mechanisms of structural disintegration of microtubules by Katanin involve heterogeneous mechanochemical processes and sensitivity of microtubules to Katanin plays significant roles in mitosis/meiosis, neurogenesis, cilia/flagella formation, cell wall development and so on. Deregulated and uncoordinated expression of Katanin has been shown to have implications in pathophysiological conditions. In this paper, we highlight mechanistic models and regulations of microtubule severing by Katanin in context of structure and various functions of Katanin in different organisms.
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Affiliation(s)
- Debasish Kumar Ghosh
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
| | - Debdeep Dasgupta
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
| | - Abhishek Guha
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
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50
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Abstract
Cell cycle transitions depend on protein phosphorylation and dephosphorylation. The discovery of cyclin-dependent kinases (CDKs) and their mode of activation by their cyclin partners explained many important aspects of cell cycle control. As the cell cycle is basically a series of recurrences of a defined set of events, protein phosphatases must obviously be as important as kinases. However, our knowledge about phosphatases lags well behind that of kinases. We still do not know which phosphatase(s) is/are truly responsible for dephosphorylating CDK substrates, and we know very little about whether and how protein phosphatases are regulated. Here, we summarize our present understanding of the phosphatases that are important in the control of the cell cycle and pose the questions that need to be answered as regards the regulation of protein phosphatases.
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