1
|
Durakoglugil MS, Wasser CR, Wong CH, Pohlkamp T, Xian X, Lane-Donovan C, Fritschle K, Naestle L, Herz J. Reelin Regulates Neuronal Excitability through Striatal-Enriched Protein Tyrosine Phosphatase (STEP 61) and Calcium Permeable AMPARs in an NMDAR-Dependent Manner. J Neurosci 2021; 41:7340-7349. [PMID: 34290083 PMCID: PMC8412985 DOI: 10.1523/jneurosci.0388-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 06/13/2021] [Accepted: 07/08/2021] [Indexed: 11/21/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tangles. Aβ oligomers cause synaptic dysfunction early in AD by enhancing long-term depression (LTD; a paradigm for forgetfulness) via metabotropic glutamate receptor (mGluR)-dependent regulation of striatal-enriched tyrosine phosphatase (STEP61). Reelin is a neuromodulator that signals through ApoE (apolipoprotein E) receptors to protect the synapse against Aβ toxicity (Durakoglugil et al., 2009) Reelin signaling is impaired by ApoE4, the most important genetic risk factor for AD, and Aβ-oligomers activate metabotropic glutamate receptors (Renner et al., 2010). We therefore asked whether Reelin might also affect mGluR-LTD. To this end, we induced chemical mGluR-LTD using DHPG (Dihydroxyphenylglycine), a selective mGluR5 agonist. We found that exogenous Reelin reduces the DHPG-induced increase in STEP61, prevents the dephosphorylation of GluA2, and concomitantly blocks mGluR-mediated LTD. By contrast, Reelin deficiency increased expression of Ca2+-permeable GluA2-lacking AMPA receptors along with higher STEP61 levels, resulting in occlusion of DHPG-induced LTD in hippocampal CA1 neurons. We propose a model in which Reelin modulates local protein synthesis as well as AMPA receptor subunit composition through modulation of mGluR-mediated signaling with implications for memory consolidation or neurodegeneration.SIGNIFICANCE STATEMENT Reelin is an important neuromodulator, which in the adult brain controls synaptic plasticity and protects against neurodegeneration. Amyloid-β has been shown to use mGluRs to induce synaptic depression through endocytosis of NMDA and AMPA receptors, a mechanism referred to as LTD, a paradigm of forgetfulness. Our results show that Reelin regulates the phosphatase STEP, which plays an important role in neurodegeneration, as well as the expression of calcium-permeable AMPA receptors, which play a role in memory formation. These data suggest that Reelin uses mGluR LTD pathways to regulate memory formation as well as neurodegeneration.
Collapse
Affiliation(s)
- Murat S Durakoglugil
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Catherine R Wasser
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Connie H Wong
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Theresa Pohlkamp
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Xunde Xian
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Courtney Lane-Donovan
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California 94158
| | | | - Lea Naestle
- Ludwig-Maximilians University of Munich, 80539, Munich, Germany
| | - Joachim Herz
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
- Departments of Neuroscience and
- Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| |
Collapse
|
2
|
Chatterjee M, Singh P, Xu J, Lombroso PJ, Kurup PK. Inhibition of striatal-enriched protein tyrosine phosphatase (STEP) activity reverses behavioral deficits in a rodent model of autism. Behav Brain Res 2020; 391:112713. [PMID: 32461127 PMCID: PMC7346720 DOI: 10.1016/j.bbr.2020.112713] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/09/2020] [Accepted: 05/15/2020] [Indexed: 02/06/2023]
Abstract
Autism spectrum disorders (ASDs) are highly prevalent childhood illnesses characterized by impairments in communication, social behavior, and repetitive behaviors. Studies have found aberrant synaptic plasticity and neuronal connectivity during the early stages of brain development and have suggested that these contribute to an increased risk for ASD. STEP is a protein tyrosine phosphatase that regulates synaptic plasticity and is implicated in several cognitive disorders. Here we test the hypothesis that STEP may contribute to some of the aberrant behaviors present in the VPA-induced mouse model of ASD. In utero VPA exposure of pregnant dams results in autistic-like behavior in the pups, which is associated with a significant increase in the STEP expression in the prefrontal cortex. The elevated STEP protein levels are correlated with increased dephosphorylation of STEP substrates GluN2B, Pyk2 and ERK, suggesting upregulated STEP activity. Moreover, pharmacological inhibition of STEP rescues the sociability, repetitive and abnormal anxiety phenotypes commonly associated with ASD. These data suggest that STEP may play a role in the VPA model of ASD and STEP inhibition may have a potential therapeutic benefit in this model.
Collapse
Affiliation(s)
- Manavi Chatterjee
- Child Study Center, Yale University, 230 South Frontage Rd, New Haven, CT 06520, United States; Department of Pharmacology, Yale University, 333 Cedar Street, New Haven, CT 06520, United States.
| | - Priya Singh
- Child Study Center, Yale University, 230 South Frontage Rd, New Haven, CT 06520, United States
| | - Jian Xu
- Child Study Center, Yale University, 230 South Frontage Rd, New Haven, CT 06520, United States; Department of Psychiatry, Yale University, 333 Cedar Street, New Haven, CT 06520, United States
| | - Paul J Lombroso
- Child Study Center, Yale University, 230 South Frontage Rd, New Haven, CT 06520, United States; Department of Psychiatry, Yale University, 333 Cedar Street, New Haven, CT 06520, United States; Department of Neuroscience, Yale University, 333 Cedar Street, New Haven, CT 06520, United States
| | - Pradeep K Kurup
- Child Study Center, Yale University, 230 South Frontage Rd, New Haven, CT 06520, United States; Department of Surgery, University of Alabama at Birmingham, 1900 University Blvd, Birmingham, AL 35233, United States.
| |
Collapse
|
3
|
Mello SS, Valente LJ, Raj N, Seoane JA, Flowers BM, McClendon J, Bieging-Rolett KT, Lee J, Ivanochko D, Kozak MM, Chang DT, Longacre TA, Koong AC, Arrowsmith CH, Kim SK, Vogel H, Wood LD, Hruban RH, Curtis C, Attardi LD. A p53 Super-tumor Suppressor Reveals a Tumor Suppressive p53-Ptpn14-Yap Axis in Pancreatic Cancer. Cancer Cell 2017; 32:460-473.e6. [PMID: 29017057 PMCID: PMC5659188 DOI: 10.1016/j.ccell.2017.09.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/19/2017] [Accepted: 09/08/2017] [Indexed: 12/25/2022]
Abstract
The p53 transcription factor is a critical barrier to pancreatic cancer progression. To unravel mechanisms of p53-mediated tumor suppression, which have remained elusive, we analyzed pancreatic cancer development in mice expressing p53 transcriptional activation domain (TAD) mutants. Surprisingly, the p5353,54 TAD2 mutant behaves as a "super-tumor suppressor," with an enhanced capacity to both suppress pancreatic cancer and transactivate select p53 target genes, including Ptpn14. Ptpn14 encodes a negative regulator of the Yap oncoprotein and is necessary and sufficient for pancreatic cancer suppression, like p53. We show that p53 deficiency promotes Yap signaling and that PTPN14 and TP53 mutations are mutually exclusive in human cancers. These studies uncover a p53-Ptpn14-Yap pathway that is integral to p53-mediated tumor suppression.
Collapse
Affiliation(s)
- Stephano S Mello
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Liz J Valente
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nitin Raj
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jose A Seoane
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Brittany M Flowers
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jacob McClendon
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kathryn T Bieging-Rolett
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jonghyeob Lee
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Danton Ivanochko
- Princess Margaret Cancer Centre, Structural Genomics Consortium and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Margaret M Kozak
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daniel T Chang
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Teri A Longacre
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Albert C Koong
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Cheryl H Arrowsmith
- Princess Margaret Cancer Centre, Structural Genomics Consortium and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Seung K Kim
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Hannes Vogel
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura D Wood
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ralph H Hruban
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christina Curtis
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura D Attardi
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
| |
Collapse
|
4
|
Wang L, Xi W, Zheng G, Zhou C, Jin G, He C, Cai M, Zhu Q. [Expression and clinical significance of PTPN14 in cholangiocarcinoma]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2015; 31:1251-1254. [PMID: 26359106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To investigate the expression level of protein tyrosine phosphatase non-receptor type 14 (PTPN14), and analyze the relationship between PTPN14 and clinical pathological features and prognosis of patients with cholangiocarcinoma. METHODS Expression of PTPN14 protein was detected by immunohistochemistry (IHC) in 57 cholangiocarcinoma tissues and corresponding adjacent normal tissues. The relationship between PTPN14 protein level and the clinical-pathological features of cholangiocarcinoma was analyzed using IBM SPSS 20.0 statistical software. The relationship between PTPN14 protein expression and 5-year overall survival of cholangiocarcinoma patients was investigated by survival curves. RESULTS IHC revealed that positive rates of PTPN14 protein were 49.1% and 75.4% in cholangiocarcinoma tissues and adjacent tissues, respectively. The expression of PTPN14 protein was significantly associated with TNM I, II, and differentiation degree of cholangiocarcinoma patients, but not significantly associated with age and gender of cholangiocarcinoma patients. The 5-year overall survival rate was higher in the PTPN14-positive patients than the PTPN14-negative ones. CONCLUSION PTPN14 was down-regulated in cholangiocarcinoma, and negatively correlated with better clinical-pathological features and 5-year overall survival rate of cholangiocarcinoma.
Collapse
Affiliation(s)
- Lijuan Wang
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Wenjin Xi
- Department of Immunology, School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China
| | - Guoxu Zheng
- Department of Immunology, School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China
| | - Congya Zhou
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Guihua Jin
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Chenchen He
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Mengjiao Cai
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| | - Qing Zhu
- Department of Oncology, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China
| |
Collapse
|
5
|
Akçakaya P, Caramuta S, Åhlen J, Ghaderi M, Berglund E, Östman A, Bränström R, Larsson C, Lui WO. microRNA expression signatures of gastrointestinal stromal tumours: associations with imatinib resistance and patient outcome. Br J Cancer 2014; 111:2091-102. [PMID: 25349971 PMCID: PMC4260040 DOI: 10.1038/bjc.2014.548] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/11/2014] [Accepted: 09/16/2014] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Gastrointestinal stromal tumour (GIST) is mainly initialised by receptor tyrosine kinase gene mutations. Although the tyrosine kinase inhibitor imatinib mesylate considerably improved the outcome of patients, imatinib resistance still remains a major therapeutic challenge in GIST therapy. Herein we evaluated the clinical impact of microRNAs in imatinib-treated GISTs. METHODS The expression levels of microRNAs were quantified using microarray and RT-qPCR in GIST specimens from patients treated with neoadjuvant imatinib. The functional roles of miR-125a-5p and PTPN18 were evaluated in GIST cells. PTPN18 expression was quantified by western blotting in GIST samples. RESULTS We showed that overexpression levels of miR-125a-5p and miR-107 were associated with imatinib resistance in GIST specimens. Functionally, miR-125a-5p expression modulated imatinib sensitivity in GIST882 cells with a homozygous KIT mutation but not in GIST48 cells with double KIT mutations. Overexpression of miR-125a-5p suppressed PTPN18 expression, and silencing of PTPN18 expression increased cell viability in GIST882 cells upon imatinib treatment. PTPN18 protein levels were significantly lower in the imatinib-resistant GISTs and inversely correlated with miR-125a-5p. Furthermore, several microRNAs were significantly associated with metastasis, KIT mutational status and survival. CONCLUSIONS Our findings highlight a novel functional role of miR-125a-5p on imatinib response through PTPN18 regulation in GIST.
Collapse
Affiliation(s)
- P Akçakaya
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - S Caramuta
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - J Åhlen
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Breast and Endocrine Surgery, Endocrine and Sarcoma Surgery Unit, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - M Ghaderi
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - E Berglund
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - A Östman
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - R Bränström
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Breast and Endocrine Surgery, Endocrine and Sarcoma Surgery Unit, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - C Larsson
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| | - W-O Lui
- Department of Oncology–Pathology, Karolinska Institutet, Stockholm, Sweden
- Cancer Center Karolinska, Karolinska University Hospital, Stockholm SE-17176, Sweden
| |
Collapse
|
6
|
Benzinou M, Clermont FF, Letteboer TGW, Kim JH, Espejel S, Harradine KA, Arbelaez J, Luu MT, Roy R, Quigley D, Higgins MN, Zaid M, Aouizerat BE, van Amstel JKP, Giraud S, Dupuis-Girod S, Lesca G, Plauchu H, Hughes CCW, Westermann CJJ, Akhurst RJ. Mouse and human strategies identify PTPN14 as a modifier of angiogenesis and hereditary haemorrhagic telangiectasia. Nat Commun 2012; 3:616. [PMID: 22233626 PMCID: PMC3509798 DOI: 10.1038/ncomms1633] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/05/2011] [Indexed: 01/21/2023] Open
Abstract
Hereditary haemorrhagic telangiectasia (HHT) [corrected] is a vascular dysplasia syndrome caused by mutations in transforming growth factor-β/bone morphogenetic protein pathway genes, ENG and ACVRL1. HHT [corrected] shows considerable variation in clinical manifestations, suggesting environmental and/or genetic modifier effects. Strain-specific penetrance of the vascular phenotypes of Eng(+/-) and Tgfb1(-/-) mice provides further support for genetic modification of transforming growth factor-β pathway deficits. We previously identified variant genomic loci, including Tgfbm2, which suppress prenatal vascular lethality of Tgfb1(-/-) mice. Here we show that human polymorphic variants of PTPN14 within the orthologous TGFBM2 locus influence clinical severity of HHT, [corrected] as assessed by development of pulmonary arteriovenous malformation. We also show that PTPN14, ACVRL1 and EFNB2, encoding EphrinB2, show interdependent expression in primary arterial endothelial cells in vitro. This suggests an involvement of PTPN14 in angiogenesis and/or arteriovenous fate, acting via EphrinB2 and ACVRL1/activin receptor-like kinase 1. These findings contribute to a deeper understanding of the molecular pathology of HHT [corrected] in particular and to angiogenesis in general.
Collapse
Affiliation(s)
- Michael Benzinou
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Frederic F. Clermont
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Tom G. W. Letteboer
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
- Department of Medical Genetics, University Medical Centre, KC04.084.2, Utrecht, The Netherlands
| | - Jai-hyun Kim
- Department of Molecular Biology and Biochemistry, UC Irvine, CA, 92697, USA
| | - Silvia Espejel
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Kelly A. Harradine
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Juan Arbelaez
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Minh Thu Luu
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Ritu Roy
- UCSF HDFCCC Biostatistical Core Facility, San Francisco, CA, 94143, USA
| | - David Quigley
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Mamie Nakayama Higgins
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Musa Zaid
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
| | - Bradley E. Aouizerat
- UCSF Department of Physiological Nursing, San Francisco, CA, 94143, USA
- UCSF Institute of Human Genetics, San Francisco, CA, 94143, USA
| | | | - Sophie Giraud
- HHT French Reference Center, Hopital Cardiologique Louis Pradel, 69500, Bron, France
| | - Sophie Dupuis-Girod
- HHT French Reference Center, Hopital Cardiologique Louis Pradel, 69500, Bron, France
| | - Gaetan Lesca
- HHT French Reference Center, Hopital Cardiologique Louis Pradel, 69500, Bron, France
| | - Henri Plauchu
- HHT French Reference Center, Hopital Cardiologique Louis Pradel, 69500, Bron, France
| | - Christopher C. W. Hughes
- Department of Molecular Biology and Biochemistry, UC Irvine, CA, 92697, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, Irvine, CA, 92697-2730, USA
| | | | - Rosemary J. Akhurst
- UCSF Helen Diller Family Comprehensive Cancer Center (HDFCCC), San Francisco, CA 94158-9001, USA
- UCSF Institute of Human Genetics, San Francisco, CA, 94143, USA
- UCSF Department of Anatomy, San Francisco, CA, 94143, USA
| |
Collapse
|
7
|
Abstract
Alzheimer's Disease (AD) is characterized by progressive loss of cognitive function, linked to marked neuronal loss. Pathological hallmarks of the disease are the accumulation of the amyloid-β (Aβ) peptide in the form of amyloid plaques and the intracellular formation of neurofibrillary tangles (NFTs). Accumulating evidence supports a key role for protein phosphorylation in both the normal and pathological actions of Aβ as well as the formation of NFTs. NFTs contain hyperphosphorylated forms of the microtubule-binding protein tau, and phosphorylation of tau by several different kinases leads to its aggregation. The protein kinases involved in the generation and/or actions of tau or Aβ are viable drug targets to prevent or alleviate AD pathology. However, it has also been recognized that the protein phosphatases that reverse the actions of these protein kinases are equally important. Here, we review recent advances in our understanding of serine/threonine and tyrosine protein phosphatases in the pathology of AD.
Collapse
|
8
|
Sette P, Mu R, Dussupt V, Jiang J, Snyder G, Smith P, Xiao TS, Bouamr F. The Phe105 loop of Alix Bro1 domain plays a key role in HIV-1 release. Structure 2011; 19:1485-95. [PMID: 21889351 PMCID: PMC3195861 DOI: 10.1016/j.str.2011.07.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 07/08/2011] [Accepted: 07/19/2011] [Indexed: 01/07/2023]
Abstract
Alix and cellular paralogs HD-PTP and Brox contain N-terminal Bro1 domains that bind ESCRT-III CHMP4. In contrast to HD-PTP and Brox, expression of the Bro1 domain of Alix alleviates HIV-1 release defects that result from interrupted access to ESCRT. In an attempt to elucidate this functional discrepancy, we solved the crystal structures of the Bro1 domains of HD-PTP and Brox. They revealed typical "boomerang" folds they share with the Bro1 Alix domain. However, they each contain unique structural features that may be relevant to their specific function(s). In particular, phenylalanine residue in position 105 (Phe105) of Alix belongs to a long loop that is unique to its Bro1 domain. Concurrently, mutation of Phe105 and surrounding residues at the tip of the loop compromise the function of Alix in HIV-1 budding without affecting its interactions with Gag or CHMP4. These studies identify a new functional determinant in the Bro1 domain of Alix.
Collapse
Affiliation(s)
- Paola Sette
- Laboratory of Molecular Microbiology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Ruiling Mu
- Laboratory of Immunology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Vincent Dussupt
- Laboratory of Molecular Microbiology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Jiansheng Jiang
- Laboratory of Immunology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Greg Snyder
- Laboratory of Immunology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Patrick Smith
- Laboratory of Immunology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Tsan. Sam Xiao
- Laboratory of Immunology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
- Corresponding authors. Laboratory of Molecular Microbiology, NIAID, NIH, 4 Center Dr, Bethesda, MD, 20892, Phone: 301 496 4099, Fax: 301 402 0226, . Laboratory of Immunology, NIAID, NIH, 4 Center Dr, Bethesda, MD, 20892, Phone: 301 402 9782, Fax: 301 480 1291,
| | - Fadila Bouamr
- Laboratory of Molecular Microbiology, Structural Immunobiology Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
- Corresponding authors. Laboratory of Molecular Microbiology, NIAID, NIH, 4 Center Dr, Bethesda, MD, 20892, Phone: 301 496 4099, Fax: 301 402 0226, . Laboratory of Immunology, NIAID, NIH, 4 Center Dr, Bethesda, MD, 20892, Phone: 301 402 9782, Fax: 301 480 1291,
| |
Collapse
|
9
|
Hnia K, Laporte J. [The myotubularin-desmin complex regulates mitochondria dynamics]. Med Sci (Paris) 2011; 27:458-60. [PMID: 21609660 DOI: 10.1051/medsci/2011275004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
MESH Headings
- Actin Cytoskeleton/ultrastructure
- Animals
- Biological Transport
- Desmin/deficiency
- Desmin/genetics
- Desmin/physiology
- Humans
- Mallory Bodies/pathology
- Mice
- Mice, Knockout
- Mitochondria, Heart/metabolism
- Mitochondria, Heart/pathology
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/pathology
- Models, Biological
- Multiprotein Complexes/physiology
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/ultrastructure
- Muscle Rigidity/genetics
- Muscular Dystrophies/genetics
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/ultrastructure
- Myopathies, Structural, Congenital/genetics
- Myopathies, Structural, Congenital/metabolism
- Phosphorylation
- Protein Processing, Post-Translational
- Protein Tyrosine Phosphatases, Non-Receptor/deficiency
- Protein Tyrosine Phosphatases, Non-Receptor/genetics
- Protein Tyrosine Phosphatases, Non-Receptor/physiology
- Recombinant Fusion Proteins/physiology
- Scoliosis/genetics
- Spinal Diseases/genetics
Collapse
|
10
|
Aguado C, Sarkar S, Korolchuk VI, Criado O, Vernia S, Boya P, Sanz P, de Córdoba SR, Knecht E, Rubinsztein DC. Laforin, the most common protein mutated in Lafora disease, regulates autophagy. Hum Mol Genet 2010; 19:2867-76. [PMID: 20453062 PMCID: PMC2893813 DOI: 10.1093/hmg/ddq190] [Citation(s) in RCA: 148] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 05/05/2010] [Indexed: 11/28/2022] Open
Abstract
Lafora disease (LD) is an autosomal recessive, progressive myoclonus epilepsy, which is characterized by the accumulation of polyglucosan inclusion bodies, called Lafora bodies, in the cytoplasm of cells in the central nervous system and in many other organs. However, it is unclear at the moment whether Lafora bodies are the cause of the disease, or whether they are secondary consequences of a primary metabolic alteration. Here we describe that the major genetic lesion that causes LD, loss-of-function of the protein laforin, impairs autophagy. This phenomenon is confirmed in cell lines from human patients, mouse embryonic fibroblasts from laforin knockout mice and in tissues from such mice. Conversely, laforin expression stimulates autophagy. Laforin regulates autophagy via the mammalian target of rapamycin kinase-dependent pathway. The changes in autophagy mediated by laforin regulate the accumulation of diverse autophagy substrates and would be predicted to impact on the Lafora body accumulation and the cell stress seen in this disease that may eventually contribute to cell death.
Collapse
Affiliation(s)
- Carmen Aguado
- Laboratory of Cellular Biology, Centro de Investigación Príncipe Felipe and CIBERER, Avda. Autopista del Saler 16, 46012 Valencia, Spain
| | - Sovan Sarkar
- Department of Medical Genetics, Cambridge Institute for Medical Research, Wellcome/MRC Building, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2XY, UK
| | - Viktor I. Korolchuk
- Department of Medical Genetics, Cambridge Institute for Medical Research, Wellcome/MRC Building, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2XY, UK
| | - Olga Criado
- Centro de Investigaciones Biológicas, CSIC and CIBERER, Ramiro de Maeztu 9, 28040 Madrid, Spain and
| | - Santiago Vernia
- Instituto de Biomedicina, CSIC and CIBERER, Jaime Roig 11, 46012 Valencia, Spain
| | - Patricia Boya
- Centro de Investigaciones Biológicas, CSIC and CIBERER, Ramiro de Maeztu 9, 28040 Madrid, Spain and
| | - Pascual Sanz
- Instituto de Biomedicina, CSIC and CIBERER, Jaime Roig 11, 46012 Valencia, Spain
| | | | - Erwin Knecht
- Laboratory of Cellular Biology, Centro de Investigación Príncipe Felipe and CIBERER, Avda. Autopista del Saler 16, 46012 Valencia, Spain
| | - David C. Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, Wellcome/MRC Building, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2XY, UK
| |
Collapse
|
11
|
Kim DJ, Tremblay ML, DiGiovanni J. Protein tyrosine phosphatases, TC-PTP, SHP1, and SHP2, cooperate in rapid dephosphorylation of Stat3 in keratinocytes following UVB irradiation. PLoS One 2010; 5:e10290. [PMID: 20421975 PMCID: PMC2858656 DOI: 10.1371/journal.pone.0010290] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 03/06/2010] [Indexed: 11/18/2022] Open
Abstract
Stat3 is initially dephosphorylated in murine keratinocytes in response to UVB irradiation. Treatment with Na3VO4 desensitized keratinocytes to UVB-induced apoptosis with the recovery of phosphorylated Stat3 protein levels, implying that a protein tyrosine phosphatase (PTP) is involved in this mechanism. In the current work, we report that three PTPs including TC45 (the nuclear form of TC-PTP), SHP1, and SHP2 are involved in this rapid dephosphorylation of Stat3 in keratinocytes induced by UVB irradiation. Dephosphorylation of Stat3 was increased rapidly after UVB irradiation of cultured keratinocytes. Knockdown of TC-PTP, SHP1, or SHP2 using RNAi showed that these PTPs are likely responsible for most of the rapid Stat3 dephosphorylation observed following UVB irradiation. The level of phosphorylated Stat3 was significantly higher in keratinocytes transfected with TC-PTP, SHP1, or SHP2 siRNA in the presence or absence of UVB compared with keratinocytes transfected with control siRNA. TC45 was mainly localized in the cytoplasm of keratinocytes and translocated from cytoplasm to nucleus upon UVB irradiation. Stat3 dephosphorylation was associated with nuclear translocation of TC45. Further studies revealed that knockdown of all three phosphatases, using RNAi, prevented the rapid dephosphorylation of Stat3 following UVB irradiation. In mouse epidermis, the level of phosphorylated Stat3 was initially decreased, followed by a significant increase at later time points after UVB exposure. The levels of Stat3 target genes, such as cyclin D1 and c-Myc, followed the changes in activated Stat3 in response to UVB irradiation. Collectively, these results suggest that three phosphatases, TC45, SHP1, and SHP2, are primarily responsible for UVB-mediated Stat3 dephosphorylation and may serve as part of an initial protective mechanism against UV skin carcinogenesis.
Collapse
MESH Headings
- Animals
- Apoptosis/radiation effects
- Cells, Cultured
- Keratinocytes/metabolism
- Keratinocytes/radiation effects
- Mice
- Phosphorylation/radiation effects
- Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics
- Protein Tyrosine Phosphatase, Non-Receptor Type 11/physiology
- Protein Tyrosine Phosphatase, Non-Receptor Type 11/radiation effects
- Protein Tyrosine Phosphatase, Non-Receptor Type 2/genetics
- Protein Tyrosine Phosphatase, Non-Receptor Type 2/physiology
- Protein Tyrosine Phosphatase, Non-Receptor Type 2/radiation effects
- Protein Tyrosine Phosphatase, Non-Receptor Type 6/genetics
- Protein Tyrosine Phosphatase, Non-Receptor Type 6/physiology
- Protein Tyrosine Phosphatase, Non-Receptor Type 6/radiation effects
- Protein Tyrosine Phosphatases, Non-Receptor/genetics
- Protein Tyrosine Phosphatases, Non-Receptor/physiology
- Protein Tyrosine Phosphatases, Non-Receptor/radiation effects
- RNA, Small Interfering/pharmacology
- STAT3 Transcription Factor/metabolism
- STAT3 Transcription Factor/radiation effects
- Ultraviolet Rays/adverse effects
Collapse
Affiliation(s)
- Dae Joon Kim
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M. D. Anderson Cancer Center, Smithville, Texas, United States of America
- * E-mail: (DJK); (JD)
| | - Michel L. Tremblay
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, McGill University, Montreal, Quebec, Canada
| | - John DiGiovanni
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M. D. Anderson Cancer Center, Smithville, Texas, United States of America
- * E-mail: (DJK); (JD)
| |
Collapse
|
12
|
Taguchi-Atarashi N, Hamasaki M, Matsunaga K, Omori H, Ktistakis NT, Yoshimori T, Noda T. Modulation of Local PtdIns3P Levels by the PI Phosphatase MTMR3 Regulates Constitutive Autophagy. Traffic 2010; 11:468-78. [PMID: 20059746 DOI: 10.1111/j.1600-0854.2010.01034.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Naoko Taguchi-Atarashi
- Department of Cellular Regulation, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-Oka, Suita, Osaka 565-0871, Japan
| | | | | | | | | | | | | |
Collapse
|
13
|
Vernia S, Rubio T, Heredia M, de Córdoba SR, Sanz P. Increased endoplasmic reticulum stress and decreased proteasomal function in lafora disease models lacking the phosphatase laforin. PLoS One 2009; 4:e5907. [PMID: 19529779 PMCID: PMC2692001 DOI: 10.1371/journal.pone.0005907] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Accepted: 05/18/2009] [Indexed: 01/03/2023] Open
Abstract
Background Lafora progressive myoclonus epilepsy (Lafora disease; LD) is a fatal autosomal recessive neurodegenerative disorder caused by loss-of-function mutations in either the EPM2A gene, encoding the dual specificity phosphatase laforin, or the EPM2B gene, encoding the E3-ubiquitin ligase malin. Previously, we and others have shown that both proteins form a functional complex that regulates glycogen synthesis by a novel mechanism involving ubiquitination and proteasomal degradation of at least two proteins, glycogen synthase and R5/PTG. Since laforin and malin localized at the endoplasmic reticulum (ER) and their regulatory role likely extend to other proteins unrelated to glycogen metabolism, we postulated that their absence may also affect the ER-unfolded protein response pathway. Methodology/Principal Findings Here, we demonstrate that siRNA silencing of laforin in Hek293 and SH-SY5Y cells increases their sensitivity to agents triggering ER-stress, which correlates with impairment of the ubiquitin-proteasomal pathway and increased apoptosis. Consistent with these findings, analysis of tissue samples from a LD patient lacking laforin, and from a laforin knockout (Epm2a-/-) mouse model of LD, demonstrates constitutive high expression levels of ER-stress markers BIP/Grp78, CHOP and PDI, among others. Conclusions/Significance We demonstrate that, in addition to regulating glycogen synthesis, laforin and malin play a role protecting cells from ER-stress, likely contributing to the elimination of unfolded proteins. These data suggest that proteasomal dysfunction and ER-stress play an important role in the pathogenesis of LD, which may offer novel therapeutic approaches for this fatal neurodegenerative disorder.
Collapse
Affiliation(s)
- Santiago Vernia
- Instituto de Biomedicina de Valencia, CSIC and CIBER de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Teresa Rubio
- Instituto de Biomedicina de Valencia, CSIC and CIBER de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Miguel Heredia
- Instituto de Biomedicina de Valencia, CSIC and CIBER de Enfermedades Raras (CIBERER), Valencia, Spain
| | | | - Pascual Sanz
- Instituto de Biomedicina de Valencia, CSIC and CIBER de Enfermedades Raras (CIBERER), Valencia, Spain
- * E-mail:
| |
Collapse
|
14
|
Dowling JJ, Vreede AP, Low SE, Gibbs EM, Kuwada JY, Bonnemann CG, Feldman EL. Loss of myotubularin function results in T-tubule disorganization in zebrafish and human myotubular myopathy. PLoS Genet 2009; 5:e1000372. [PMID: 19197364 PMCID: PMC2631153 DOI: 10.1371/journal.pgen.1000372] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Accepted: 01/07/2009] [Indexed: 11/26/2022] Open
Abstract
Myotubularin is a lipid phosphatase implicated in endosomal trafficking in vitro, but with an unknown function in vivo. Mutations in myotubularin cause myotubular myopathy, a devastating congenital myopathy with unclear pathogenesis and no current therapies. Myotubular myopathy was the first described of a growing list of conditions caused by mutations in proteins implicated in membrane trafficking. To advance the understanding of myotubularin function and disease pathogenesis, we have created a zebrafish model of myotubular myopathy using morpholino antisense technology. Zebrafish with reduced levels of myotubularin have significantly impaired motor function and obvious histopathologic changes in their muscle. These changes include abnormally shaped and positioned nuclei and myofiber hypotrophy. These findings are consistent with those observed in the human disease. We demonstrate for the first time that myotubularin functions to regulate PI3P levels in a vertebrate in vivo, and that homologous myotubularin-related proteins can functionally compensate for the loss of myotubularin. Finally, we identify abnormalities in the tubulo-reticular network in muscle from myotubularin zebrafish morphants and correlate these changes with abnormalities in T-tubule organization in biopsies from patients with myotubular myopathy. In all, we have generated a new model of myotubular myopathy and employed this model to uncover a novel function for myotubularin and a new pathomechanism for the human disease that may explain the weakness associated with the condition (defective excitation–contraction coupling). In addition, our findings of tubuloreticular abnormalities and defective excitation-contraction coupling mechanistically link myotubular myopathy with several other inherited muscle diseases, most notably those due to ryanodine receptor mutations. Based on our findings, we speculate that congenital myopathies, usually considered entities with similar clinical features but very disparate pathomechanisms, may at their root be disorders of calcium homeostasis. Congenital myopathies are inherited muscle conditions typically presenting in early childhood. They are individually rare, but as a group are likely as common as conditions such as muscular dystrophy. The zebrafish is an emerging experimental system for the study of myopathies. We have utilized the zebrafish to develop a model of myotubular myopathy, one of the most severe childhood muscle diseases and a condition whose pathogenesis is poorly understood. We have generated fish that have the characteristic behavioral and histological features of human myotubular myopathy. Using this model, we then made novel insights into the pathogenesis of myotubular myopathy, including the identification of abnormalities in the muscle tubulo-reticular system. We subsequently identified similar changes in muscle from patients with myotubular myopathy, corroborating the importance of our zebrafish findings. Because a functional tubulo-reticular complex is required for normal muscle contraction, we speculate that the weakness observed in myotubular myopathy is caused by breakdown of this network. In all, our study is the first to identify a potential pathomechanism to explain the clinical features of myotubular myopathy. Furthermore, by revealing abnormalities in the tubulo-reticular system, we provide a novel link between myotubular myopathy and several other congenital myopathies.
Collapse
MESH Headings
- Animals
- Disease Models, Animal
- Embryo, Nonmammalian/metabolism
- Fluorescent Antibody Technique
- Homeostasis
- Humans
- Muscle Fibers, Skeletal/pathology
- Muscle Fibers, Skeletal/ultrastructure
- Muscle, Skeletal/metabolism
- Mutation
- Myopathies, Structural, Congenital/etiology
- Myopathies, Structural, Congenital/metabolism
- Myopathies, Structural, Congenital/pathology
- Protein Tyrosine Phosphatases, Non-Receptor/genetics
- Protein Tyrosine Phosphatases, Non-Receptor/physiology
- Zebrafish/genetics
- Zebrafish/metabolism
Collapse
Affiliation(s)
- James J Dowling
- Department of Pediatrics, University of Michigan Medical Center, Ann Arbor, Michigan, USA.
| | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
Charcot-Marie-Tooth type 4B (CMT4B) is a severe autosomal recessive neuropathy with demyelination and myelin outfoldings of the nerve. This disorder is genetically heterogeneous, but thus far, mutations in myotubularin-related 2 (MTMR2) and MTMR13 genes have been shown to underlie CMT4B1 and CMT4B2, respectively. MTMR2 and MTMR13 belong to a family of ubiquitously expressed proteins sharing homology with protein tyrosine phosphatases (PTPs). The MTMR family, which has 14 members in humans, comprises catalytically active proteins, such as MTMR2, and catalytically inactive proteins, such as MTMR13. Despite their homology with PTPs, catalytically active MTMR phosphatases dephosphorylate both PtdIns3P and PtdIns(3,5)P2 phosphoinositides. Thus, MTMR2 and MTMR13 may regulate vesicular trafficking in Schwann cells. Loss of these proteins could lead to uncontrolled folding of myelin and, ultimately, to CMT4B. In this review, we discuss recent findings on this interesting protein family with the main focus on MTMR2 and MTMR13 and their involvement in the biology of Schwann cell and CMT4B neuropathies.
Collapse
Affiliation(s)
- Stefano C Previtali
- Neuropathology Unit, Department of Neurology, San Raffaele Scientific Institute, Milan, Italy
| | | | | |
Collapse
|