1
|
Bondada V, Gal J, Mashburn C, Rodgers DW, Larochelle KE, Croall DE, Geddes JW. The C2 domain of calpain 5 contributes to enzyme activation and membrane localization. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119019. [PMID: 33811937 DOI: 10.1016/j.bbamcr.2021.119019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 02/28/2021] [Accepted: 03/19/2021] [Indexed: 10/21/2022]
Abstract
The enzymatic characteristics of the ubiquitous calpain 5 (CAPN5) remain undescribed despite its high expression in the central nervous system and links to eye development and disease. CAPN5 contains the typical protease core domains but lacks the C terminal penta-EF hand domain of classical calpains, and instead contains a putative C2 domain. This study used the SH-SY5Y neuroblastoma cell line stably transfected with CAPN5-3xFLAG variants to assess the potential roles of the CAPN5 C2 domain in Ca2+ regulated enzyme activity and intracellular localization. Calcium dependent autoproteolysis of CAPN5 was documented and characterized. Mutation of the catalytic Cys81 to Ala or addition of EGTA prevented autolysis. Eighty μM Ca2+ was sufficient to stimulate half-maximal CAPN5 autolysis in cellular lysates. CAPN5 autolysis was inhibited by tri-leucine peptidyl aldehydes, but less effectively by di-Leu aldehydes, consistent with a more open conformation of the protease core relative to classical calpains. In silico modeling revealed a type II topology C2 domain including loops with the potential to bind calcium. Mutation of the acidic amino acid residues predicted to participate in Ca2+ binding, particularly Asp531 and Asp589, resulted in a decrease of CAPN5 membrane association. These residues were also found to be invariant in several genomes. The autolytic fragment of CAPN5 was prevalent in membrane-enriched fractions, but not in cytosolic fractions, suggesting that membrane association facilitates the autoproteolytic activity of CAPN5. Together, these results demonstrate that CAPN5 undergoes Ca2+-activated autoproteolytic processing and suggest that CAPN5 association with membranes enhances CAPN5 autolysis.
Collapse
Affiliation(s)
- Vimala Bondada
- Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Jozsef Gal
- Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, USA; Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Charles Mashburn
- Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - David W Rodgers
- Department of Molecular and Cellular Biochemistry, Center for Structural Biology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | | | - Dorothy E Croall
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, ME, USA
| | - James W Geddes
- Spinal Cord and Brain Injury Research Center, College of Medicine, University of Kentucky, Lexington, KY, USA; Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, USA.
| |
Collapse
|
2
|
Smestad JA, Maher LJ. Master regulator analysis of paragangliomas carrying SDHx, VHL, or MAML3 genetic alterations. BMC Cancer 2019; 19:619. [PMID: 31234811 PMCID: PMC6591808 DOI: 10.1186/s12885-019-5813-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 06/10/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Succinate dehydrogenase (SDH) loss and mastermind-like 3 (MAML3) translocation are two clinically important genetic alterations that correlate with increased rates of metastasis in subtypes of human paraganglioma and pheochromocytoma (PPGL) neuroendocrine tumors. Although hypotheses propose that succinate accumulation after SDH loss poisons dioxygenases and activates pseudohypoxia and epigenomic hypermethylation, it remains unclear whether these mechanisms account for oncogenic transcriptional patterns. Additionally, MAML3 translocation has recently been identified as a genetic alteration in PPGL, but is poorly understood. We hypothesize that a key to understanding tumorigenesis driven by these genetic alterations is identification of the transcription factors responsible for the observed oncogenic transcriptional changes. METHODS We leverage publicly-available human tumor gene expression profiling experiments (N = 179) to reconstruct a PPGL tumor-specific transcriptional network. We subsequently use the inferred transcriptional network to perform master regulator analyses nominating transcription factors predicted to control oncogenic transcription in specific PPGL molecular subtypes. Results are validated by analysis of an independent collection of PPGL tumor specimens (N = 188). We then perform a similar master regulator analysis in SDH-loss mouse embryonic fibroblasts (MEFs) to infer aspects of SDH loss master regulator response conserved across species and tissue types. RESULTS A small number of master regulator transcription factors are predicted to drive the observed subtype-specific gene expression patterns in SDH loss and MAML3 translocation-positive PPGL. Interestingly, although EPAS1 perturbation is detectible in SDH-loss and VHL-loss tumors, it is by no means the most potent factor driving observed patterns of transcriptional dysregulation. Analysis of conserved SDH-loss master regulators in human tumors and MEFs implicated ZNF423, a known modulator of retinoic acid response in neuroblastoma. Subsequent functional analysis revealed a blunted cell death response to retinoic acid in SDH-loss MEFs and blunted differentiation response in SDH-inhibited SH-SY5Y neuroblastoma cells. CONCLUSIONS The unbiased analyses presented here nominate specific transcription factors that are likely drivers of oncogenic transcription in PPGL tumors. This information has the potential to be exploited for targeted therapy. Additionally, the observation that SDH loss or inhibition results in blunted retinoic acid response suggests a potential developmental etiology for this tumor subtype.
Collapse
Affiliation(s)
- John A Smestad
- Mayo Clinic Medical Scientist Training Program, Mayo Clinic College of Medicine and Science, Rochester, MN, USA.,Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - L James Maher
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA.
| |
Collapse
|
3
|
Roumes H, Brossaud J, Lemelletier A, Moisan MP, Pallet V, Redonnet A, Corcuff JB. Retinoids and glucocorticoids have opposite effects on actin cytoskeleton rearrangement in hippocampal HT22 cells. Int J Biochem Cell Biol 2015; 71:102-110. [PMID: 26748244 DOI: 10.1016/j.biocel.2015.12.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/18/2015] [Accepted: 12/28/2015] [Indexed: 12/12/2022]
Abstract
A chronic excess of glucocorticoids elicits deleterious effects in the hippocampus. Conversely, retinoic acid plays a major role in aging brain plasticity. As synaptic plasticity depends on mechanisms related to cell morphology, we investigated the involvement of retinoic acid and glucocorticoids in the remodelling of the HT22 neurons actin cytoskeleton. Cells exhibited a significantly more elongated shape with retinoic acid and a rounder shape with dexamethasone; retinoic acid reversed the effects of dexamethasone. Actin expression and abundance were unchanged by retinoic acid or dexamethasone but F-actin organization was dramatically modified. Indeed, retinoic acid and dexamethasone increased (70 ± 7% and 176 ± 5%) cortical actin while retinoic acid suppressed the effect of dexamethasone (90 ± 6%). Retinoic acid decreased (-22 ± 9%) and dexamethasone increased (134 ± 16%) actin stress fibres. Retinoic acid also suppressed the effect of dexamethasone (-21 ± 7%). Spectrin is a key protein in the actin network remodelling. Its abundance was decreased by retinoic acid and increased by dexamethasone (-21 ± 11% and 52 ± 10%). However, retinoic acid did not modify the effect of dexamethasone (48 ± 7%). Calpain activity on spectrin was increased by retinoic acid and decreased by dexamethasone (26 ± 14% and -57 ± 5%); retinoic acid mildly but significantly modified the effect of dexamethasone (-44 ± 7%). The calpain inhibitor calpeptin suppressed the effects of retinoic acid and dexamethasone on cell shape and actin stress fibres remodelling but did not modify the effects on cortical actin. Retinoic acid and dexamethasone have a dramatic but mainly opposite effect on actin cytoskeleton remodelling. These effects originate, at least partly, from calpain activity.
Collapse
Affiliation(s)
- Hélène Roumes
- INRA, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France
| | - Julie Brossaud
- University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; Laboratoire d'Hormonologie, Service de médecine nucléaire, CHU Bordeaux, 33604 Pessac, France
| | - Aloïs Lemelletier
- INRA, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France
| | - Marie-Pierre Moisan
- INRA, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France
| | - Véronique Pallet
- University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; IPB, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France
| | - Anabelle Redonnet
- INRA, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France
| | - Jean-Benoît Corcuff
- University Bordeaux, Nutrition et neurobiologie intégrée, UMR 1286, 33076 Bordeaux, France; Laboratoire d'Hormonologie, Service de médecine nucléaire, CHU Bordeaux, 33604 Pessac, France.
| |
Collapse
|
4
|
Jin N, Yin X, Gu J, Zhang X, Shi J, Qian W, Ji Y, Cao M, Gu X, Ding F, Iqbal K, Gong CX, Liu F. Truncation and Activation of Dual Specificity Tyrosine Phosphorylation-regulated Kinase 1A by Calpain I: A MOLECULAR MECHANISM LINKED TO TAU PATHOLOGY IN ALZHEIMER DISEASE. J Biol Chem 2015; 290:15219-37. [PMID: 25918155 PMCID: PMC4463463 DOI: 10.1074/jbc.m115.645507] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/14/2015] [Indexed: 11/06/2022] Open
Abstract
Hyperphosphorylation and dysregulation of exon 10 splicing of Tau are pivotally involved in pathogenesis of Alzheimer disease (AD) and/or other tauopathies. Alternative splicing of Tau exon 10, which encodes the second microtubule-binding repeat, generates Tau isoforms containing three and four microtubule-binding repeats, termed 3R-Taus and 4R-Taus, respectively. Dual specificity tyrosine-phosphorylation-regulated kinase 1A (Dyrk1A) lies at the Down syndrome critical region of chromosome 21. Overexpression of this kinase may contribute to the early Tau pathology in Down syndrome via phosphorylation of Tau and dysregulation of Tau exon 10. Here, we report that Dyrk1A was truncated at the C terminus and was associated with overactivation of calpain I in AD brain. Calpain I proteolyzed Dyrk1A in vitro first at the C terminus and further at the N terminus and enhanced its kinase activity toward Tau via increased Vmax but not Km. C-terminal truncation of Dyrk1A resulted in stronger activity than its full-length protein in promotion of exon 10 exclusion and phosphorylation of Tau. Dyrk1A was truncated in kainic acid-induced excitotoxic mouse brains and coincided with an increase in 3R-Tau expression and phosphorylation of Tau via calpain activation. Moreover, truncation of Dyrk1A was correlated with an increase in the ratio of 3R-Tau/4R-Tau and Tau hyperphosphorylation in AD brain. Collectively, these findings suggest that truncation/activation of Dyrk1A by Ca(2+)/calpain I might contribute to Tau pathology via promotion of exon 10 exclusion and hyperphosphorylation of Tau in AD brain.
Collapse
Affiliation(s)
- Nana Jin
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314
| | - Xiaomin Yin
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, the Department of Biochemistry and Molecular Biology, School of Medicine Sciences, Nantong University, Nantong, Jiangsu 226001, China, and
| | - Jianlan Gu
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, the Department of Biochemistry and Molecular Biology, School of Medicine Sciences, Nantong University, Nantong, Jiangsu 226001, China, and
| | - Xinhua Zhang
- the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314
| | - Jianhua Shi
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, the Department of Biochemistry and Molecular Biology, School of Medicine Sciences, Nantong University, Nantong, Jiangsu 226001, China, and
| | - Wei Qian
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Biochemistry and Molecular Biology, School of Medicine Sciences, Nantong University, Nantong, Jiangsu 226001, China, and
| | - Yuhua Ji
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Maohong Cao
- the Department of Neurology, Hospital Affiliated with Nantong University, Nantong, Jiangsu 226001, China
| | - Xiaosong Gu
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Fei Ding
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Khalid Iqbal
- the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314
| | - Cheng-Xin Gong
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314
| | - Fei Liu
- From the Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China, the Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314,
| |
Collapse
|
5
|
Jin N, Yin X, Yu D, Cao M, Gong CX, Iqbal K, Ding F, Gu X, Liu F. Truncation and activation of GSK-3β by calpain I: a molecular mechanism links to tau hyperphosphorylation in Alzheimer's disease. Sci Rep 2015; 5:8187. [PMID: 25641096 PMCID: PMC4313118 DOI: 10.1038/srep08187] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 01/07/2015] [Indexed: 12/17/2022] Open
Abstract
Abnormal hyperphosphorylation of tau is pivotally involved in the pathogenesis of Alzheimer's disease (AD) and related tauopathies. Glycogen synthase kinase 3β (GSK-3β) is a primary tau kinase that is most implicated in tau pathology in AD. However, the exact molecular nature of GSK-3β involved in AD is unclear. In the present study, we found that GSK-3β was truncated at C-terminus and correlated with over-activation of calpain I in AD brain. Truncation of GSK-3β was positively correlated with tau hyperphosphorylation, tangles score and Braak stage in human brain. Calpain I proteolyzed GSK-3β in vitro at C-terminus, leading to an increase of its kinase activity, but keeping its characteristic to preferentially phosphorylate the protein kinase A-primed tau. Excitotoxicity induced by kainic acid (KA) caused GSK-3β truncation at C-terminus and hyperphosphorylation of tau in mouse brain. Inhibition of calpain prevented the KA-induced changes. These findings suggest that truncation of GSK-3β by Ca2+/calpain I markedly increases its activity and involvement of this mechanism probably is responsible for up-regulation of GSK-3β and consequent abnormal hyperphosphorylation of tau and neurofibrillary degeneration in AD.
Collapse
Affiliation(s)
- Nana Jin
- 1] Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China [2] Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Xiaomin Yin
- 1] Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China [2] Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Dian Yu
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Maohong Cao
- Institute of Neurology, Department of Neurology, Hospital Affiliated to Nantong University, Nantong, Jiangsu 226001, P. R. China
| | - Cheng-Xin Gong
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Khalid Iqbal
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| | - Fei Ding
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China
| | - Xiaosong Gu
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China
| | - Fei Liu
- 1] Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China [2] Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
| |
Collapse
|
6
|
Petroni D, Tsai J, Mondal D, George W. Attenuation of low dose methylmercury and glutamate induced-cytotoxicity and tau phosphorylation by an N-methyl-D-aspartate antagonist in human neuroblastoma (SHSY5Y) cells. ENVIRONMENTAL TOXICOLOGY 2013; 28:700-706. [PMID: 21976409 DOI: 10.1002/tox.20765] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Revised: 07/12/2011] [Accepted: 07/22/2011] [Indexed: 05/31/2023]
Abstract
Methylmercury (MeHg), a known neurotoxin, has been reported to alter glutamate homeostasis in the neuronal environment resulting in excitotoxicity. This study was conducted to investigate whether, and if so, under what conditions, that low dose MeHg would enhance the toxicity of glutamate and to what extent that blockade of NMDA receptors would alter MeHg and glutamate's toxicity in cultured neuroblastoma cells. Neuroblastoma cells (SH-SY5Y) were used in a cell culture model to study effects of MeHg, glutamate (glu), a calcium chelator (BAPTA-AM), and a noncompetitive NMDA antagonist, MK-801 on cell growth, cell survival, and phosphorylation of tau protein, as a measure of cellular events associated with tauopathies. Exposure of cells to a combination of MeHg (50 nM) and glutamate (1 mM) resulted in both a greater decrease in cell viability as well as a greater induction in tau phosphorylation, as compared to exposures with MeHg and glutamate alone. MK-801, an NMDA receptor antagonist, and the intracellular calcium chelator, BAPTA-AM, both significantly inhibited tau hyperphosphorylation and protected cells from the effects of combination exposures to glutamate and MeHg. These results may indicate that exposure to even nontoxic levels of MeHg may prime neuronal cells to be more susceptible to neuronal injury from excitotoxicants such as glutamate and thus may increase the likelihood of neurological disease states. In conclusion, low-dose MeHg-induced toxicity may be related to an increase in the cellular response to glutamate and that NMDA receptor antagonists may provide a potential treatment for MeHg-associated neurological diseases.
Collapse
Affiliation(s)
- Daniel Petroni
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA
| | | | | | | |
Collapse
|
7
|
Taniguchi T, Tanaka S, Ishii A, Watanabe M, Fujitani N, Sugeo A, Gotoh S, Ohta T, Hiyoshi M, Matsuzaki H, Sakai N, Konishi H. A brain-specific Grb2-associated regulator of extracellular signal-regulated kinase (Erk)/mitogen-activated protein kinase (MAPK) (GAREM) subtype, GAREM2, contributes to neurite outgrowth of neuroblastoma cells by regulating Erk signaling. J Biol Chem 2013; 288:29934-42. [PMID: 24003223 DOI: 10.1074/jbc.m113.492520] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Grb2-associated regulator of Erk/MAPK1 (GAREM) is an adaptor molecule in the EGF-mediated signaling pathway. GAREM is expressed ubiquitously in human organs and cultured cells. Two GAREM homologues are encoded by the human genome. Therefore, previously identified GAREM is named GAREM1. Here we characterized a new subtype of GAREM, GAREM2, that is specifically expressed in the mouse, rat, and human brain. Three GAREM2 tyrosines (Tyr-102, Tyr-429, and Tyr-551) are phosphorylated upon EGF stimulation and are necessary for binding to Grb2. Furthermore, GAREM2 and Shp2 regulate Erk activity in EGF-stimulated cells. These characteristics are similar to those of GAREM1. GAREM2 is expressed in some neuroblastoma cell lines and is also tyrosine-phosphorylated and bound to Grb2 after treatment with EGF. Eventually, GAREM2 regulates Erk activation in the presence of EGF or insulin like growth factor 1. GAREM2 also regulates insulin-like growth factor 1-induced neuronal differentiation of the SH-SY5Y neuroblastoma cell line. Although the structure and function of both GAREM subtypes are similar, GAREM1 is recruited into the nucleus and GAREM2 is not. Nuclear localization of GAREM1 might be controlled by a GAREM1-specific nuclear localization sequence and 14-3-3ε binding. The N-terminal 20 amino acids of GAREM1 make up its nuclear localization sequence that is also a 14-3-3ε binding site. The GAREM family is a new class of adaptor molecules with subtype-specific biological functions.
Collapse
Affiliation(s)
- Tomonori Taniguchi
- From the Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Shobara, Hiroshima 727-0023, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Computational investigation of the key factors affecting the second stage activation mechanisms of domain II m-calpain. J Mol Model 2013; 19:779-92. [DOI: 10.1007/s00894-012-1604-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 09/21/2012] [Indexed: 10/27/2022]
|
9
|
Petroni D, Tsai J, Agrawal K, Mondal D, George W. Low-dose methylmercury-induced oxidative stress, cytotoxicity, and tau-hyperphosphorylation in human neuroblastoma (SH-SY5Y) cells. ENVIRONMENTAL TOXICOLOGY 2012; 27:549-555. [PMID: 21254321 DOI: 10.1002/tox.20672] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 10/12/2010] [Accepted: 10/15/2010] [Indexed: 05/28/2023]
Abstract
Acute neurotoxic effects of high-dose methylmercury (MeHg) in humans have been well documented in the scientific literature. However, low-dose effects are less well described. This study was designed to evaluate the effects of low-dose MeHg (<100 nM) on human brain cells in a tissue culture model. Neuroblastoma (NB) cells (SH-SY5Y) were used in the cell culture model to study low-dose effects of MeHg on cell growth, cell survival, reactive oxygen species (ROS), and the phosphorylation of tau protein, as a measure of potential markers of cellular events associated with tauopathies. When cells were incubated in culture with MeHg (50 and 100 nM), there were significant decreases in cell viability as well as significant increase in ROS generation as determined by fluorescent dye analysis (H(2)DCFDA). Furthermore, a concomitant decrease in glutathione levels to 25% of control was observed at both 50 and 100 nM MeHg. In addition, the level of phosphorylated tau was significantly increased after treatment at both 50 and 100 nM MeHg, compared with controls. Pretreatment of NB cells with the antioxidant, N-acetylcysteine (1.25 mM) and the calpain inhibitor, MDL-28170 (10 μM), significantly attenuated the effects of MeHg (50 and 100 nM) on cell viability as well as on tau phosphorylation. These results indicate that low-dose MeHg toxicity may be related to an induction of tau phosphorylation through an oxidative stress-dependent mechanism and that blockade of this pathway may attenuate the toxic effects of MeHg.
Collapse
Affiliation(s)
- Daniel Petroni
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | | | | | | | | |
Collapse
|
10
|
Li C, Chen S, Yue P, Deng X, Lonial S, Khuri FR, Sun SY. Proteasome inhibitor PS-341 (bortezomib) induces calpain-dependent IkappaB(alpha) degradation. J Biol Chem 2010; 285:16096-104. [PMID: 20335171 DOI: 10.1074/jbc.m109.072694] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The proteasome, a key component of the ubiquitin-proteasome pathway, has emerged as an important cancer therapeutic target. PS-341 (also called Bortezomib or Velcade) is the first proteasome inhibitor approved for newly diagnosed and relapsed multiple myeloma and is currently being tested in many clinical trials against other types of cancers. One proposed mechanism by which PS-341 exerts its anticancer effect is inactivation of nuclear factor-kappaB (NF-kappaB) through prevention of IkappaB(alpha) degradation. In this study, we show that PS-341 at concentrations that effectively inhibited the growth of human cancer cells, instead of increasing IkappaB(alpha) stability, paradoxically induced IkappaB(alpha) degradation. As a result, PS-341 facilitated p65 nuclear translocation and increased NF-kappaB activity. Moreover, IkappaB(alpha) degradation by PS-341 occurred early before induction of apoptosis and could not be inhibited by a pan-caspase inhibitor or caspase-8 silencing; however, it could be prevented with calpain inhibitors, calcium-chelating agents, calpain knockdown, or calpastatin overexpression. In agreement, PS-341 increased calpain activity. These data together indicate that PS-341 induces a calpain-mediated IkappaB(alpha) degradation independent of caspases. In the presence of a calpain inhibitor, the apoptosis-inducing activity of PS-341 was dramatically enhanced. Collectively, these unexpected findings suggest not only a novel paradigm regarding the relationship between proteasome inhibition and NF-kappaB activity but also a strategy to enhance the anticancer efficacy of PS-341.
Collapse
Affiliation(s)
- Chunyang Li
- Department of Hematology and Medical Oncology, Emory University School of Medicine and Winship Cancer Institute, Atlanta, Georgia 30322, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
The calpain family of proteases is causally linked to postischemic neurodegeneration. However, the precise mechanisms by which calpains contribute to postischemic neuronal death have not been fully elucidated. This review outlines the key features of the calpain system, and the evidence for its causal role in postischemic neuronal pathology. Furthermore, the consequences of specific calpain substrate cleavage at various subcellular locations are explored. Calpain substrates within synapses, plasma membrane, endoplasmic reticulum, lysosomes, mitochondria, and the nucleus, as well as the overall effect of postischemic calpain activity on calcium regulation and cell death signaling are considered. Finally, potential pathways for calpain-mediated neurodegeneration are outlined in an effort to guide future studies aimed at understanding the downstream pathology of postischemic calpain activity and identifying optimal therapeutic strategies.
Collapse
Affiliation(s)
- Matthew B Bevers
- Department of Emergency Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-4283, USA
| | | |
Collapse
|
12
|
Kowara R, Moraleja KL, Chakravarthy B. Involvement of nitric oxide synthase and ROS-mediated activation of L-type voltage-gated Ca2+ channels in NMDA-induced DPYSL3 degradation. Brain Res 2006; 1119:40-9. [PMID: 16987501 DOI: 10.1016/j.brainres.2006.08.047] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 08/11/2006] [Accepted: 08/12/2006] [Indexed: 01/27/2023]
Abstract
Dihydropyrimidinase-like 3 (DPYSL3), a member of TUC (TOAD-64/Ulip/CRMP), is believed to play a role in neuronal differentiation, axonal outgrowth and possibly in neuronal regeneration. Recently, we have shown that in primary cortical neurons (PCN) NMDA and oxidative stress (H(2)O(2)) caused a calpain-dependent cleavage of DPYSL3 (62 kDa) resulting in the appearance of a lower molecular weight form (60 kDa) of DPYSL3. Our preliminary results had shown that antioxidants significantly reduced NMDA-induced DPYSL3 degradation, indicating involvement of ROS in calpain activation. The aim of this study was to investigate the possible involvement of NOS in NMDA-induced DPYSL3 degradation. We found that NOS inhibitor (L-NAME) significantly prevented NMDA-induced ROS formation, as well as intracellular Ca(2+) increase [Ca(2+)](i), DPYSL3 degradation and cell death. Further, exposure of PCN to NO donor (SNP) resulted in significant [Ca(2+)](i) increase, ROS generation and probable calpain-mediated DPYSL3 truncation. The NMDA- and oxidative stress (ROS)-induced DPYSL3 truncation was totally dependent on extracellular [Ca(2+)](i). While NMDA-induced DPYSL3 truncation was blocked by both NMDA receptor antagonist (MK801) [Kowara, R., Chen, Q., Milliken, M., Chakravarthy, B., 2005. Calpain-mediated degradation of dihydropyrimidinase-like 3 protein (DPYSL3) in response to NMDA and H(2)O(2) toxicity. J. Neurochem. 95 (2), 466-474] and L-VGCC (nimodipine) inhibitors, H(2)O(2)-induced increase in [Ca(2+)](i), ROS generation and DPYSL3 truncation was blocked only by nimodipine. These results indicate that changes in Ca(2+) homeostasis resulting from ROS-dependent activation of L-VGCC are sufficient to induce probable calpain-mediated DPYSL3 truncation and demonstrate for the first time the role of ROS in the mechanism leading to glutamate-induced calpain activation and DPYSL3 protein degradation. The probable calpain-mediated DPYSL3 truncation may have significant impact on its interaction with actin and its assembly, and in turn on growth cone integrity.
Collapse
Affiliation(s)
- Renata Kowara
- National Research Council, Institute for Biological Sciences, M-54, Ottawa, Ontario, Canada K1A 0R6.
| | | | | |
Collapse
|
13
|
Di Primio C, Marracci S, Cecchettini A, Nardi I, Giorgi F, Fausto AM, Gambellini G, Mazzini M. Differential tissue expression of a calpastatin isoform in Xenopus embryos. Micron 2006; 38:268-77. [PMID: 16824766 DOI: 10.1016/j.micron.2006.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 04/24/2006] [Accepted: 04/25/2006] [Indexed: 11/18/2022]
Abstract
This study is aimed at demonstrating the role played by a calpastatin isoform (Xcalp3) in Xenopus embryos. A specific monoclonal antibody (mAb) was raised against a glutathione S-transferase (GST)-Xcalp3 fusion protein and characterized by immunoblotting and confocal fluorescence microscopy on stage 20-36 embryos. Under these conditions, calpastatin reactivity is associated with a major 110kDa protein fraction and preferentially expressed by notochord and somitic cells. In notochord cells, anti-calpastatin reactive sites were initially restricted to the luminal space of the vacuoles and later became diffused throughout the cytoplasm. In contrast, anti-calpastatin reactive sites in somitic cells were initially diffused throughout the cytoplasm and became restricted to a few intracellular granules in the later developmental stages. At the ultrastructural level, notochord cells appeared as flattened discs containing several vacuoles and numerous electron-dense granules. During transition from stages 26 to 32, electron-dense granules were gradually reduced in number as vacuoles enlarged in size and losed their calpastatin reactivity. Electron-dense granules were also present in myoblast cells and their number gradually reduced during development. To determine whether these observations bear any causal relationship to the calpain/calpastatin system, a number of Xenopus embryos were examined both ultrastructurally and histochemically following exposure to a specific calpain inhibitor (CI3). Under these conditions, Xenopus embryos exhibited an altered right-left symmetry and an abnormal axial shortening. In CI3-treated stage 32 embryos, notochord cells had a reduced vacuolar extension and exhibited at the same time an increase in granular content. The overall morphology of the somites was also distorted and myoblasts were altered both in shape and granular content. Based on these findings, it is concluded that the calpain/calpastatin may play an important role in the control of notochord elongation and somite differentiation during Xenopus embryogenesis.
Collapse
Affiliation(s)
- C Di Primio
- Department of Physiology and Biochemistry, University of Pisa, Italy
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Axelsson V, Holback S, Sjögren M, Gustafsson H, Forsby A. Gliotoxin induces caspase-dependent neurite degeneration and calpain-mediated general cytotoxicity in differentiated human neuroblastoma SH-SY5Y cells. Biochem Biophys Res Commun 2006; 345:1068-74. [PMID: 16712786 DOI: 10.1016/j.bbrc.2006.05.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Accepted: 05/04/2006] [Indexed: 02/05/2023]
Abstract
In this study, a significant increase by 50% in intracellular free calcium concentration ([Ca(2+)](i)) was observed in differentiated human neuroblastoma (SH-SY5Y) cells after exposure to 0.25microM of the fungal metabolite gliotoxin for 72h. Further, the involvement of caspases and calpains was demonstrated to underlie the gliotoxin-induced cytotoxic and neurite degenerative effects. The caspase inhibitor Z-VAD-fmk almost completely reduced the neurite degeneration from 40% degeneration of neurites to 5% as compared to control. Inhibition of calpains with calpeptin significantly attenuated gliotoxin-induced cytotoxicity, determined as reduction in total cellular protein content, from 43% to 14% as compared to control cells. Western blot analyses of alphaII-spectrin breakdown fragments confirmed activity of the proteases, and that alphaII-spectrin was cleaved by caspases in gliotoxin-exposed cells. These results show that calpains and caspases have a role in the toxicity of gliotoxin in differentiated SH-SY5Y cells and that the process may be Ca(2+)-mediated.
Collapse
Affiliation(s)
- V Axelsson
- Department of Neurochemistry, The Arrhenius Laboratories for Natural Sciences, Stockholm University, Sweden.
| | | | | | | | | |
Collapse
|
15
|
Mehendale HM, Limaye PB. Calpain: a death protein that mediates progression of liver injury. Trends Pharmacol Sci 2005; 26:232-6. [PMID: 15860369 DOI: 10.1016/j.tips.2005.03.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Calpain is a Ca(2+)-regulated cytosolic cysteine protease that exists mainly in two isoforms and mediates crucial cellular functions, including rearrangement of cytoskeletal proteins, transport of the glucose transporter GLUT4, and protein cleavage to activate various receptors and pro-enzymes. Unintentional activation or functional loss of intracellular calpain has been implicated in several pathologies, including neurodegenerative diseases, traumatic brain and spinal cord injuries, cataracts and ischemia-associated injuries. Furthermore, polymorphism in the gene encoding calpain-10 has been associated with increased risk of type 2 diabetes. Recent studies have revealed a novel role for calpain in the progression of toxicant-induced liver damage. Evidence suggests that calpain leaking out of necrotic hepatocytes is highly activated in the extracellular milieu and hydrolyzes proteins in the plasma membrane of neighboring cells leading to progression of injury. Experimental intervention with calpain inhibitors substantially mitigates progression of liver injury initiated by toxicants, thereby preventing acute liver failure, and toxicant-induced animal death, pointing to a new potential therapeutic strategy against acute toxicities.
Collapse
Affiliation(s)
- Harihara M Mehendale
- Department of Toxicology, School of Pharmacy, College of Health Sciences, The University of Louisiana at Monroe, 700 University Avenue, Monroe, LA 71209 USA.
| | | |
Collapse
|
16
|
Tremper-Wells B, Vallano ML. Nuclear calpain regulates Ca2+-dependent signaling via proteolysis of nuclear Ca2+/calmodulin-dependent protein kinase type IV in cultured neurons. J Biol Chem 2004; 280:2165-75. [PMID: 15537635 DOI: 10.1074/jbc.m410591200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Accumulating evidence indicates that calpains can reside in or translocate to the cell nucleus, but their functions in this compartment remain poorly understood. Dissociated cultures of cerebellar granule cells (GCs) demonstrate improved long-term survival when their growth medium is supplemented with depolarizing agents that stimulate Ca(2+) influx and activate calmodulin-dependent signaling cascades, notably 20 mm KCl. We previously observed Ca(2+)-dependent down-regulation of Ca(2+)/calmodulin-dependent protein kinase (CaMK) type IV, which was attenuated by calpain inhibitors, in GCs supplemented with 20 mm KCl (Tremper-Wells, B., Mathur, A., Beaman-Hall, C. M., and Vallano, M. L. (2002) J. Neurochem. 81, 314-324). CaMKIV is highly enriched in the nucleus and thought to be critical for improved survival. Here, we demonstrate by immunolocalization/confocal microscopy and subcellular fractionation that the regulatory and catalytic subunits of m-calpain are enriched in GC nuclei, including GCs grown in medium containing 5 mm KCl. Calpain-mediated proteolysis of CaMKIV is selective, as several other nuclear and non-nuclear calpain substrates were not degraded under chronic depolarizing culture conditions. Depolarization and Ca(2+)-dependent down-regulation of CaMKIV were associated with significant alterations in other components of the Ca(2+)-CaMKIV signaling cascade: the ratio of phosphorylated to total cAMP response element-binding protein (a downstream CaMKIV substrate) was reduced by approximately 10-fold, and the amount of CaMK kinase (an upstream activator of CaMKIV) protein and mRNA was significantly reduced. We hypothesize that calpain-mediated CaMKIV proteolysis is an autoregulatory feedback response to sustained activation of a Ca(2+)-CaMKIV signaling pathway, resulting from growth of cultures in medium containing 25 mm KCl. This study establishes nuclear m-calpain as a regulator of CaMKIV and associated signaling molecules under conditions of sustained Ca(2+) influx.
Collapse
Affiliation(s)
- Barbara Tremper-Wells
- Department of Neuroscience and Physiology, State University of New York Upstate Medical University, Syracuse, New York 13210, USA
| | | |
Collapse
|
17
|
Abstract
Numerous lines of evidence demonstrate that calpains, a family of 14 Ca(2+)-activated neutral cysteine proteases, are involved in oncotic cell death in a variety of models. At this time, the biochemistry of most calpains and the specific roles of different calpains in physiology and pathology remain to be determined. A number of calpain substrates have been identified in cellular systems, including cytoskeletal proteins, and recent studies suggest that calpains mediate the increase in plasma membrane permeability to ions and the progressive breakdown of the plasma membrane observed in oncosis through the proteolysis of cystokeletal and plasma membrane proteins. Further, a number of reports provide evidence that the mitochondrial dysfunction observed in oncosis may be mediated by a mitochondrial calpain of unknown identity. Finally, a number of diverse calpain inhibitors have been developed that show cytoprotective properties in cellular systems and in vivo following diverse insults. It is suggested that future research be directed toward elucidation of the role(s) of specific calpain isozymes in physiological and pathological conditions; identifying and linking specific calpain substrates with altered cellular functions; and developing cell-permeable, potent, isozyme-selective calpain inhibitors.
Collapse
Affiliation(s)
- Xiuli Liu
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
| | | | | |
Collapse
|
18
|
McCollum AT, Jafarifar F, Chan R, Guttmann RP. Oxidative stress inhibits ionomycin-mediated cell death in cortical neurons. J Neurosci Res 2004; 76:104-9. [PMID: 15048934 DOI: 10.1002/jnr.20059] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Thiol-proteases play important roles in many cellular processes, including maintenance of protein homeostasis and execution of cell death. Therefore, determining how this family of enzymes is regulated is critical for our understanding of both physiological and pathological conditions. Because these proteases require a reduced cysteine residue for activity, the cellular redox state plays a crucial role in regulating the activity of thiol proteases. Importantly, increased oxidative stress can result in the direct modification of the active site cysteine, leading to enzyme inactivation. This would suggest that oxidative stress that occurs during pathological insults could prolong cell survival by preventing the execution of thiol-protease-dependent cell death pathways. To test this hypothesis, cultured rat cortical neurons were treated with the oxidizing agent diamide or doxorubicin in the presence or absence of the calcium ionophore ionomycin. Under normoxic conditions, ionomycin treatment resulted in approximately 70% cell death, which was prevented by addition of the calpain-selective inhibitor benyzloxycarbonyl-Leu-Leu-Tyr fluoromethylketone. Similarly, pretreatment of neurons with either oxidant was also protective. Protection resulting from oxidative stress was not due to new protein synthesis, insofar as cycloheximide did not affect oxidant-mediated protection. Interestingly, treatment with the antioxidant Trolox to reverse or prevent oxidative stress blocked the protective effects of both oxidants against ionomycin-induced cell death. We interpret these findings to suggest that, in diseases or conditions in which oxidative stress is increased, the ability of thiol-proteases to execute cell death pathways fully is decreased and may prolong cell survival.
Collapse
Affiliation(s)
- Adrian T McCollum
- Department of Physiology, University of Kentucky, Lexington, Kentucky 40536, USA
| | | | | | | |
Collapse
|
19
|
Abstract
Calpains are a family of calcium-dependent cysteine proteases under complex cellular regulation. By making selective limited proteolytic cleavages, they modulate the activity of enzymes, including key signaling molecules, and induce specific cytoskeletal rearrangements, accounting for their roles in cell motility, signal transduction, vesicular trafficking and structural stabilization. Calpain activation has been implicated in various aging phenomena and diseases of late life, including cataract formation, erythrocyte senescence, diabetes mellitus type 2, hypertension, arthritis, and neurodegenerative disorders. The early and pervasive involvement of calpains in Alzheimer's disease potentially influences the development of beta-amyloid and tau disturbances and their consequences for neurodegeneration and neuronal cell loss.
Collapse
Affiliation(s)
- Ralph A Nixon
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY 10962, USA.
| |
Collapse
|
20
|
Kim M, Roh JK, Yoon BW, Kang L, Kim YJ, Aronin N, DiFiglia M. Huntingtin is degraded to small fragments by calpain after ischemic injury. Exp Neurol 2003; 183:109-15. [PMID: 12957494 DOI: 10.1016/s0014-4886(03)00132-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gene defect in Huntington's disease (HD) causes a polyglutamine expansion in the N-terminal region of huntingtin (N-htt). In vitro studies suggest that mutant N-htt fragments can aggregate and cause cell death in HD. The physiological and pathological conditions that affect htt proteolysis in the brain are unclear. We examined htt expression by Western blot in the rat brain after transient ischemic injury, which causes striatal neurodegeneration similar to that seen in HD and activates proteases including calcium-dependent calpains. Focal brain ischemia reduced levels of full-length htt in the infarcted cortex and striatum and increased expression of a 55-kDa N-htt fragment that was also produced by treating control brain extracts with calpain. N-htt fragments between 65 and 80 kDa also rose after injury, but these fragments were not as long-lived as the 55-kDa N-htt fragment. The results suggest that after ischemic injury full-length htt is degraded in degenerating neurons and an N-htt fragment accumulates.
Collapse
Affiliation(s)
- Manho Kim
- Department of Neurology, Clinical Research Institute, Seoul National University Hospital, Seoul, South Korea
| | | | | | | | | | | | | |
Collapse
|
21
|
Vu D, Marin P, Walzer C, Cathieni MM, Bianchi EN, Saïdji F, Leuba G, Bouras C, Savioz A. Transcription regulator LMO4 interferes with neuritogenesis in human SH-SY5Y neuroblastoma cells. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2003; 115:93-103. [PMID: 12877980 DOI: 10.1016/s0169-328x(03)00119-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
LMO4 is a transcription regulator interacting with proteins involved, among else, in tumorigenesis. Its function in the nervous system, and particularly in the adult nervous system, has however still to be elucidated. We decided to modify its expression in a neuronal model, human SH-SY5Y neuroblastoma cells, by permanent transfection of sense or anti-sense Lmo4 cDNAs. Generated clones overexpressing the Lmo4 transcript in sense orientation tended to aggregate. They showed significantly reduced average number of neurites per cell and average neuritic length per cell. The opposite was observed with clones overexpressing the anti-sense Lmo4 transcript. Furthermore, selected clones were subjected to 72 h long-term treatments with retinoic acid and phorbol ester (TPA), two biochemicals known to stimulate differentiation of non-transfected SH-SY5Y cells and other neuroblastoma cells. Neuritogenesis occurred after retinoic acid stimulation in all cases. The inhibitory effect of sense Lmo4 RNA overexpression on neuritic outgrowth was indeed prevented. The protein kinase C activator TPA could not induce neuritogenesis in SH-SY5Y cells overexpressing sense Lmo4 RNA. Thus, sense Lmo4 RNA overexpression, not Lmo4 endogenous transcription, overrides the stimulatory effect of TPA upon neuritic outgrowth. We also showed that Lmo4-dependent neuritic retraction and outgrowth correspond to altered phosphorylation of cytoskeletal proteins. Overall, Lmo4 RNA overexpression interferes with neuritic outgrowth, whereas anti-sense Lmo4 RNA expression favors neuritogenesis in SH-SY5Y cells. Consequently, changes in Lmo4 RNA expression levels might alter the rate of neuritic outgrowth in the developing and adult nervous system.
Collapse
Affiliation(s)
- Dung Vu
- Department of Psychiatry, University of Geneva School of Medicine, CH-1225, Geneva, Switzerland
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Sedarous M, Keramaris E, O'Hare M, Melloni E, Slack RS, Elce JS, Greer PA, Park DS. Calpains mediate p53 activation and neuronal death evoked by DNA damage. J Biol Chem 2003; 278:26031-8. [PMID: 12721303 DOI: 10.1074/jbc.m302833200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
DNA damage is an initiator of neuronal death implicated in neuropathological conditions such as stroke. Previous evidence has shown that apoptotic death of embryonic cortical neurons treated with the DNA damaging agent camptothecin is dependent upon the tumor suppressor p53, an upstream death mediator, and more distal death effectors such as caspases. We show here that the calcium-regulated cysteine proteases, calpains, are activated during DNA damage induced by camptothecin treatment. Moreover, calpain deficiency, calpastatin expression, or pharmacological calpain inhibitors prevent the death of embryonic cortical neurons, indicating the important role of calpain in DNA damage-induced death. Calpain inhibition also significantly reduced and delayed the induction of p53. Consistent with the actions of calpains upstream of p53 and the proximal nature of p53 death signaling, calpain inhibition inhibited cytochrome c release and DEVD-AFC cleavage activity. Taken together, our results indicate that calpains are a key mediator of p53 induction and consequent caspase-dependent neuronal death due to DNA damage.
Collapse
Affiliation(s)
- Mary Sedarous
- Ottawa Health Research Institute, Neuroscience Group, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Hong J, Yoshida K, Rosner MR. Characterization of a cysteine proteinase inhibitor induced during neuronal cell differentiation. J Neurochem 2002; 81:922-34. [PMID: 12065604 DOI: 10.1046/j.1471-4159.2002.00882.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A rat homolog of human cystatin E/M was identified by differential display of transcripts induced during neuronal cell differentiation. A member of the family 2 cystatins, rat cystatin E/M is secreted, glycosylated and developmentally regulated. Rat cystatin E/M is expressed in brain, and is induced during differentiation of a conditionally immortalized E17 rat hippocampal cell line (H19-7) by bFGF or activated Raf via MEK-dependent and -independent signaling pathways. Rat cystatin E/M protein is increased post-transcriptionally in PC12 cells, and the protein is secreted into the medium of primary embryonal hippocampal cultures. Analysis of the K (i) of recombinant His-tagged rat cystatin E/M toward cathepsins B and H revealed that rat cystatin E/M has an inhibitor profile distinct from that of other members of the cystatin family. Motif swapping between rat cystatin E/M and human cystatin C, a well-characterized cystatin, identified some residues that can contribute to the specificity of inhibition. Taken together, these results describe a member of the cystatin family that has a distinct inhibitor profile and may play a role in neuronal development.
Collapse
Affiliation(s)
- Jia Hong
- Department of Neurobiology, Pharmacology and Physiology, University of Chicago, Chicago, Illinois 60637, USA
| | | | | |
Collapse
|
24
|
Liu X, Rainey JJ, Harriman JF, Schnellmann RG. Calpains mediate acute renal cell death: role of autolysis and translocation. Am J Physiol Renal Physiol 2001; 281:F728-38. [PMID: 11553520 DOI: 10.1152/ajprenal.2001.281.4.f728] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The goals of this study were to determine 1) the expression of calpain isoforms in rabbit renal proximal tubules (RPT); 2) calpain autolysis and translocation, and calpastatin levels during RPT injury; and 3) the effect of a calpain inhibitor (PD-150606) on calpain levels, mitochondrial function, and ion transport during RPT injury. RT-PCR, immunoblot analysis, and FITC-casein zymography demonstrated the presence of only mu- and m-calpains in rabbit RPT. The mitochondrial inhibitor antimycin A decreased RPT mu- and m-calpain and calpastatin levels in conjunction with cell death and increased plasma membrane permeability. No increases in either mu- or m-calpain were observed in the membrane nor were increases observed in autolytic forms of either mu- or m-calpain in antimycin A-exposed RPT. PD-150606 blocked antimycin A-induced cell death, preserved calpain levels in antimycin A-exposed RPT, and promoted the recovery of mitochondrial function and active Na+ transport in RPT after hypoxia and reoxygenation. The present study suggests that calpains mediate RPT injury without undergoing autolysis or translocation, and ultimately they leak from cells subsequent to RPT injury/death. Furthermore, PD-150606 allows functional recovery after injury.
Collapse
Affiliation(s)
- X Liu
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | | | | | | |
Collapse
|
25
|
Tucholski J, Lesort M, Johnson GV. Tissue transglutaminase is essential for neurite outgrowth in human neuroblastoma SH-SY5Y cells. Neuroscience 2001; 102:481-91. [PMID: 11166134 DOI: 10.1016/s0306-4522(00)00482-6] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Tissue transglutaminase is a normal constituent of the central and peripheral nervous systems and in rats transglutaminase activity in brain and spinal cord is highest during fetal stages when axonal outgrowth is occurring. Further, treatment of human neuroblastoma SH-SY5Y cells with retinoic acid results in the cells withdrawing from the cell cycle and extending neurites, in the same time frame that tissue transglutaminase expression significantly increases. Considering these and other previous findings, this study was carried out to determine whether tissue transglutaminase is involved in neuronal differentiation of SH-SY5Y cells. For these studies SH-SY5Y cells stably overexpressing wild-type tissue transglutaminase, an inactive tissue transglutaminase mutant (C277S) or an antisense tissue transglutaminase construct (which decreased endogenous tissue transglutaminase below detectable levels) were used. SH-SY5Y cells overexpressing wild-type tissue transglutaminase spontaneously differentiated into a neuronal phenotype when grown in low-serum media. In contrast, cells overexpressing inactive tissue transglutaminase or the antisense tissue transglutaminase continued to proliferate and exhibit a flat polygenic morphology even when maintained in low-serum conditions. In addition, increased tissue transglutaminase expression in response to retinoic acid was abolished in the antisense tissue transglutaminase cells, and antisense and mutant tissue transglutaminase expressing cells did not extend neurites in response to retinoic acid. Moreover, wild-type and inactive tissue transglutaminase exhibited differential intracellular localization. These data indicate that tissue transglutaminase is necessary and sufficient for neuronal differentiation of human neuroblastoma SH-SY5Y cells.
Collapse
Affiliation(s)
- J Tucholski
- Department of Psychiatry and Behavioral Neurobiology, 1720 7th Ave. South, SC 1061, University of Alabama at Birmingham, AL 35294-0017, Birmingham, USA
| | | | | |
Collapse
|
26
|
Raghunath M, Patti R, Bannerman P, Lee CM, Baker S, Sutton LN, Phillips PC, Damodar Reddy C. A novel kinase, AATYK induces and promotes neuronal differentiation in a human neuroblastoma (SH-SY5Y) cell line. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2000; 77:151-62. [PMID: 10837911 DOI: 10.1016/s0169-328x(00)00048-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Apoptosis Associated Tyrosine Kinase (AATYK), a novel protein recently isolated from differentiating 32D mouse myeloid cells, contains a putative tyrosine kinase domain and several binding motifs for src homology 2 (SH-2) and src homology 3 (SH-3) domain containing proteins. We observed that AATYK is expressed in different regions of the brain. Although it might play a role in normal nervous system development by modulating apoptosis, little is known regarding its function in the brain or its intracellular localization and kinase activity. Recognizing its homology with Insulin like growth factor-I (IGF-I) receptor (IGF-IR) and the critical role of IGF-I in neuronal survival, we hypothesized that AATYK plays an important role in neuronal differentiation/apoptosis. To test this hypothesis, we transfected the human adrenergic neuroblastoma (NB):SH-SY5Y cells with AATYK cDNA under a tetracycline-repressible promoter and established stable cell lines that readily express AATYK on removal of tetracycline. AATYK immunoprecipitated from these cell lysates is an active kinase. Indirect immunofluorescent staining of the clones revealed AATYK to be localized in the cytoplasm. By itself, AATYK overexpression for short duration (2-3 days) did not induce differentiation in the stable SH-SY5Y clones. On the other hand, overexpression for longer periods (7-8 days) per se, significantly (P<0.05-0.001) increased the percent of differentiated cells as well as the neurite length. AATYK-induced differentiation was in the same range as the differentiation induced by agents like all-trans retinoic acid (RA), 12-O-Tetradecanoyl phorbol 13-acetate (TPA) and IGF-I. In addition, AATYK significantly promoted the neuronal differentiation induced by these agents. Our results demonstrate for the first time that AATYK is an active, non-receptor, cytosolic kinase which induces neuronal differentiation and also promotes differentiation induced by other agents in the SH-SY5Y cells.
Collapse
Affiliation(s)
- M Raghunath
- Division of Neuro-Oncology, Children's Hospital of Philadelphia, Philadelphia, PA, 19104 USA
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Wilson MT, Kisaalita WS, Keith CH. Glutamate-induced changes in the pattern of hippocampal dendrite outgrowth: a role for calcium-dependent pathways and the microtubule cytoskeleton. JOURNAL OF NEUROBIOLOGY 2000; 43:159-72. [PMID: 10770845 DOI: 10.1002/(sici)1097-4695(200005)43:2<159::aid-neu6>3.0.co;2-n] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Glutamate regulation of a variety of aspects of dendrite development may be involved in neuronal plasticity and neuropathology. In this study, we examine the calcium-dependent pathways and alterations in the microtubule (MT) cytoskeleton that may mediate glutamate-induced changes in the pattern of dendrite outgrowth. We used Fura-2 AM and inhibitors of the calcium-dependent proteins, calmodulin and calpain, to identify the role of specific calcium-dependent pathways in glutamate-regulated dendrite outgrowth. Additionally, we used a quantitative fluorescence technique to correlate changes in MT levels with glutamate-induced changes in dendrite outgrowth. We show that the intracellular calcium concentration ([Ca(2+)](i)) changes in a biphasic manner over a 12-h period in the presence of glutamate. A transient increase in [Ca(2+)](i) over the first hour of glutamate exposure correlated with a calmodulin-associated increase in the rate of dendrite outgrowth, whereas a sustained increase in [Ca(2+)](i) was correlated with calpain-associated dendrite retraction. Quantitative fluorescence measurements showed no net change in the level of MTs during calmodulin-associated increases in dendrite outgrowth, but showed a significant decline in the level of MTs during calpain-associated dendrite retraction. These findings provide insights into the intracellular mechanisms involved in activity-dependent regulation of dendrite morphology during development and after pathology.
Collapse
Affiliation(s)
- M T Wilson
- BD Transduction Laboratories, Lexington, Kentucky 40503, USA
| | | | | |
Collapse
|
28
|
Temm-Grove CJ, Wert D, Thompson VF, Allen RE, Goll DE. Microinjection of calpastatin inhibits fusion in myoblasts. Exp Cell Res 1999; 247:293-303. [PMID: 10047471 DOI: 10.1006/excr.1998.4362] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rat satellite cells (RSC) were microinjected with purified calpastatin or m-calpain, and myoblasts from a C2C12 mouse line were microinjected with purified calpastatin. Microinjection with calpastatin completely prevented fusion of myoblasts from both sources, whereas microinjection with m-calpain significantly increased the rate of fusion of cultured RSC; 44% of the nuclei of RSC cultures were in multinucleated myotubes within 48 h after microinjection with m-calpain plus labeled dextran, whereas only 15% of the nuclei were in multinucleated myotubes after microinjection with dextran alone. Western analyses indicated that neither RSC nor C2C12 myoblasts contained detectable amounts of mu-calpain before fusion. The levels of calpastatin in C2C12 myoblasts increased as cells passed from the proliferative stage to the onset of fusion, and these levels increased substantially in both the C2C12 and the RSC cells as they progressed to the late or postfusion stage. Both RSC and C2C12 myoblasts contained an 80-kDa polypeptide that was labeled with an anti-m-calpain antibody in Western blots. The results are consistent with a role of the calpain system (m-calpain in these myoblast lines) in remodeling of the cytoskeletal/plasma membrane interactions during cell fusion.
Collapse
Affiliation(s)
- C J Temm-Grove
- Muscle Biology Group, University of Arizona, Tucson, Arizona, 85721, USA
| | | | | | | | | |
Collapse
|
29
|
Newcomb JK, Pike BR, Zhao X, Banik NL, Hayes RL. Altered calpastatin protein levels following traumatic brain injury in rat. J Neurotrauma 1999; 16:1-11. [PMID: 9989462 DOI: 10.1089/neu.1999.16.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pathological activation of the intracellular Ca2+-dependent proteases calpains may be responsible for the neuronal pathology associated with neurodegenerative diseases and acute traumas to the central nervous system. Though calpain activation has been shown definitively in traumatic brain injury (TBI), no studies have investigated calpastatin (CAST), the calpains' endogenous and specific inhibitor, after TBI. The present study examined temporal changes in CAST protein following controlled cortical impact injury in the rat. Western blot analyses of CAST in cortex and hippocampus detected two bands corresponding to molecular weights of 130 kDa [high-molecular-weight (HMW)] and 80 kDa [low-molecular-weight (LMW)]. A modest decrease in the HMW band in conjunction with a significant increase in the LMW band was observed in cortex ipsilateral to the site of impact following TBI. Examination of ipsilateral hippocampus revealed an increasing trend in the LMW band after injury, while no changes were observed in the HMW band. Thus, observable changes in CAST levels appear to occur several hours after reported calpain activation and cleavage of other substrates. In addition, a new analysis was performed on previously published data examining calpain activity in the same tissue samples used in the present study. These data suggest an association between decreases in calpain activity and accumulation of LMW CAST in the ipsilateral cortex following TBI. The present study cannot exclude proteolytic processing of CAST to LMW forms. However, the absence of reciprocity between changes in LMW and HMW bands in consistent with other data suggesting that rat brain could contain different CAST isoforms.
Collapse
Affiliation(s)
- J K Newcomb
- Department of Neurosurgery, Vivian L. Smith Center for Neurologic Research, University of Texas-Houston Health Science Center, 77030, USA
| | | | | | | | | |
Collapse
|
30
|
Kakkar R, Raju RV, Sharma RK. In vitro generation of an active calmodulin-independent phosphodiesterase from brain calmodulin-dependent phosphodiesterase (PDE1A2) by m-calpain. Arch Biochem Biophys 1998; 358:320-8. [PMID: 9784246 DOI: 10.1006/abbi.1998.0858] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present study we have shown that bovine brain 60-kDa calmodulin-dependent cyclic nucleotide phosphodiesterase isozyme (CaMPDE - PDE1A2) is proteolyzed by a Ca2+-dependent cysteine protease, m-calpain. The proteolysis of PDE1A2 by m-calpain results in its conversion to a totally calmodulin (CaM)-independent form accompanied by degradation of PDE1A2 into a 45-kDa catalytic fragment and a 15-kDa fragment. The activity of PDE1A2 is unaffected by the presence or absence of CaM during cleavage, suggesting that the interaction between CaM and PDE1A2 does not alter substrate recognition by calpain. Furthermore, we provide evidence, based on the studies of CaM overlay and phosphorylation, that the cleavage site is not present either in the CaM-binding domain or phosphorylation site. N-terminal sequence analysis of the 45-kDa fragment indicated that cleavage occurs between residues 126Gln and 127Ala, and eliminates the CaM-dependent activity of carboxy termini PDE1A2. The present findings suggest that limited proteolysis in the brain through calpains could be an alternate mechanism for activating CaMPDE(s) and for regulating intracellular levels of cAMP.
Collapse
Affiliation(s)
- R Kakkar
- College of Medicine, University of Saskatchewan, Saskatoon, S7N 4H4, Canada
| | | | | |
Collapse
|
31
|
Affiliation(s)
- E Carafoli
- Institute of Biochemistry, Swiss Federal Institute of Technology (ETH), Zurich, 8092, Switzerland
| | | |
Collapse
|