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Zhang W, Zhang J, Zhang Z, Cha S, Li J, Chen L, Wu J, Teng J, Guo G, Zhang J. Effects of DeSUMOylated Spastin on AMPA Receptor Surface Delivery and Synaptic Function Are Enhanced by Phosphorylating at Ser210. Mol Neurobiol 2024; 61:6045-6059. [PMID: 38267753 DOI: 10.1007/s12035-024-03935-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 01/09/2024] [Indexed: 01/26/2024]
Abstract
Surface trafficking of AMPA receptors (AMPARs) is one of the important mechanisms mediating synaptic plasticity which is essential for cognitive functions such as learning and memory. Spastin, as a novel binding partner for the AMPAR, has been reported to regulate AMPAR surface expression and synaptic function. Additionally, Spastin undergoes two posttranslational modifications, phosphorylation and SUMOylation, both of which are crucial for synaptic function. However, gaps exist in our knowledge of how Spastin phosphorylation cross-talks with its SUMOylation in the regulation of AMPAR surface expression and synaptic function. Here, we reported that deSUMOylation of Spastin at Lys427 increased the surface level of AMPAR GluA2 subunit, the amplitude and frequency of miniature excitatory synaptic currents (mEPSC), and facilitated the morphological maturation of dendritic spines in cultured hippocampal neurons. Further studies demonstrated that Spastin phosphorylation at Ser210 further increased the enhancement of GluA2 surface expression and synaptic function by deSUMOylated Spastin, while dephosphorylation had the opposite effect. Simultaneously, deSUMOylation at Lys427 significantly increased the promoting effect of Spastin phosphorylation on synaptic function. In conclusion, our study suggests that cooperative interactions between phosphorylated and deSUMOylated Spastin are novel pathways to enhance synaptic function.
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Affiliation(s)
- Wenbin Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
- Department of Surgery, The First Clinical Medical College, Jinan University, Guangzhou, 510630, China
| | - Jiaqi Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Zhongqi Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
- Department of Anesthesiology, The Affiliated Shunde Hospital of Jinan University, Foshan, 528305, China
| | - Shuhan Cha
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
| | - Jiong Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
| | - Li Chen
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
| | - Jiaming Wu
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China
| | - Jijun Teng
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266011, China.
| | - Guoqing Guo
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China.
| | - Jifeng Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, 510630, China.
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Liu Q, Yang H, Luo J, Peng C, Wang K, Zhang G, Lin H, Ji Z. 14-3-3 protein augments the protein stability of phosphorylated spastin and promotes the recovery of spinal cord injury through its agonist intervention. eLife 2024; 12:RP90184. [PMID: 38231910 PMCID: PMC10945579 DOI: 10.7554/elife.90184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024] Open
Abstract
Axon regeneration is abortive in the central nervous system following injury. Orchestrating microtubule dynamics has emerged as a promising approach to improve axonal regeneration. The microtubule severing enzyme spastin is essential for axonal development and regeneration through remodeling of microtubule arrangement. To date, however, little is known regarding the mechanisms underlying spastin action in neural regeneration after spinal cord injury. Here, we use glutathione transferase pulldown and immunoprecipitation assays to demonstrate that 14-3-3 interacts with spastin, both in vivo and in vitro, via spastin Ser233 phosphorylation. Moreover, we show that 14-3-3 protects spastin from degradation by inhibiting the ubiquitination pathway and upregulates the spastin-dependent severing ability. Furthermore, the 14-3-3 agonist Fusicoccin (FC-A) promotes neurite outgrowth and regeneration in vitro which needs spastin activation. Western blot and immunofluorescence results revealed that 14-3-3 protein is upregulated in the neuronal compartment after spinal cord injury in vivo. In addition, administration of FC-A not only promotes locomotor recovery, but also nerve regeneration following spinal cord injury in both contusion and lateral hemisection models; however, the application of spastin inhibitor spastazoline successfully reverses these phenomena. Taken together, these results indicate that 14-3-3 is a molecular switch that regulates spastin protein levels, and the small molecule 14-3-3 agonist FC-A effectively mediates the recovery of spinal cord injury in mice which requires spastin participation.
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Affiliation(s)
- Qiuling Liu
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Hua Yang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Jianxian Luo
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Cheng Peng
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Ke Wang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Guowei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Hongsheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Zhisheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
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Sardina F, Conte A, Paladino S, Pierantoni GM, Rinaldo C. HIPK2 in the physiology of nervous system and its implications in neurological disorders. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119465. [PMID: 36935052 DOI: 10.1016/j.bbamcr.2023.119465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 03/21/2023]
Abstract
HIPK2 is an evolutionary conserved serine/threonine kinase with multifunctional roles in stress response, embryonic development and pathological conditions, such as cancer and fibrosis. The heterogeneity of its interactors and targets makes HIPK2 activity strongly dependent on the cellular context, and allows it to modulate multiple signaling pathways, ultimately regulating cell fate and proliferation. HIPK2 is highly expressed in the central and peripheral nervous systems, and its genetic ablation causes neurological defects in mice. Moreover, HIPK2 is involved in processes, such as endoplasmic reticulum stress response and protein aggregate accumulation, and pathways, including TGF-β and BMP signaling, that are crucial in the pathogenesis of neurological disorders. Here, we review the data about the role of HIPK2 in neuronal development, survival, and homeostasis, highlighting the implications in the pathogenesis of neurological disorders, and pointing out HIPK2 potentiality as therapeutic target and diagnostic or prognostic marker.
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Affiliation(s)
- F Sardina
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University, Rome, Italy
| | - A Conte
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy
| | - S Paladino
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy
| | - G M Pierantoni
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy.
| | - C Rinaldo
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University, Rome, Italy.
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Sardina F, Valente D, Fattorini G, Cioffi E, Zanna GD, Tessa A, Trisciuoglio D, Soddu S, Santorelli FM, Casali C, Rinaldo C. New cellular imaging-based method to distinguish the SPG4 subtype of hereditary spastic paraplegia. Eur J Neurol 2023; 30:1734-1744. [PMID: 36815539 DOI: 10.1111/ene.15756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/07/2023] [Accepted: 02/16/2023] [Indexed: 02/24/2023]
Abstract
BACKGROUND AND PURPOSE Microtubule defects are a common feature in several neurodegenerative disorders, including hereditary spastic paraplegia. The most frequent form of hereditary spastic paraplegia is caused by mutations in the SPG4/SPAST gene, encoding the microtubule severing enzyme spastin. To date, there is no effective therapy available but spastin-enhancing therapeutic approaches are emerging; thus prognostic and predictive biomarkers are urgently required. METHODS An automated, simple, fast and non-invasive cell imaging-based method was developed to quantify microtubule cytoskeleton organization changes in lymphoblastoid cells and peripheral blood mononuclear cells. RESULTS It was observed that lymphoblastoid cells and peripheral blood mononuclear cells from individuals affected by SPG4-hereditary spastic paraplegia show a polarized microtubule cytoskeleton organization. In a pilot study on freshly isolated peripheral blood mononuclear cells, our method discriminates SPG4-hereditary spastic paraplegia from healthy donors and other hereditary spastic paraplegia subtypes. In addition, it is shown that our method can detect the effects of spastin protein level changes. CONCLUSIONS These findings open the possibility of a rapid, non-invasive, inexpensive test useful to recognize SPG4-hereditary spastic paraplegia subtype and evaluate the effects of spastin-enhancing drug in non-neuronal cells.
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Affiliation(s)
- Francesca Sardina
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University of Rome, Rome, Italy
| | - Davide Valente
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University of Rome, Rome, Italy
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | - Gaia Fattorini
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University of Rome, Rome, Italy
- Department of Biology and Biotechnology, "Charles Darwin" Sapienza University of Rome, Rome, Italy
| | - Ettore Cioffi
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy
| | - Gianmarco Dalla Zanna
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy
| | | | - Daniela Trisciuoglio
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University of Rome, Rome, Italy
| | - Silvia Soddu
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | | | - Carlo Casali
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy
| | - Cinzia Rinaldo
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), c/o Sapienza University of Rome, Rome, Italy
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Conte A, Valente V, Paladino S, Pierantoni GM. HIPK2 in cancer biology and therapy: Recent findings and future perspectives. Cell Signal 2023; 101:110491. [PMID: 36241057 DOI: 10.1016/j.cellsig.2022.110491] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 11/06/2022]
Abstract
Homeodomain-interacting protein kinase 2 (HIPK2) is a serine-threonine kinase that phosphorylates and regulates a plethora of transcriptional regulators and chromatin modifiers. The heterogeneity of its interactome allows HIPK2 to modulate several cellular processes and signaling pathways, ultimately regulating cell fate and proliferation. Because of its p53-dependent pro-apoptotic activity and its downregulation in many tumor types, HIPK2 is traditionally considered a bone fide tumor suppressor gene. However, recent findings revealed that the role of HIPK2 in the pathogenesis of cancer is much more complex, ranging from tumor suppressive to oncogenic, strongly depending on the cellular context. Here, we review the very recent data emerged in the last years about the involvement of HIPK2 in cancer biology and therapy, highlighting the various alterations of this kinase (downregulation, upregulation, mutations and/or delocalization) in dependence on the cancer types. In addition, we discuss the recent advancement in the understanding the tumor suppressive and oncogenic functions of HIPK2, its role in establishing the response to cancer therapies, and its regulation by cancer-associated microRNAs. All these data strengthen the idea that HIPK2 is a key player in many types of cancer; therefore, it could represent an important prognostic marker, a factor to predict therapy response, and even a therapeutic target itself.
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Affiliation(s)
- Andrea Conte
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy.
| | - Valeria Valente
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Simona Paladino
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Giovanna Maria Pierantoni
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy.
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Costa AC, Sousa MM. The Role of Spastin in Axon Biology. Front Cell Dev Biol 2022; 10:934522. [PMID: 35865632 PMCID: PMC9294387 DOI: 10.3389/fcell.2022.934522] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/07/2022] [Indexed: 12/05/2022] Open
Abstract
Neurons are highly polarized cells with elaborate shapes that allow them to perform their function. In neurons, microtubule organization—length, density, and dynamics—are essential for the establishment of polarity, growth, and transport. A mounting body of evidence shows that modulation of the microtubule cytoskeleton by microtubule-associated proteins fine tunes key aspects of neuronal cell biology. In this respect, microtubule severing enzymes—spastin, katanin and fidgetin—a group of microtubule-associated proteins that bind to and generate internal breaks in the microtubule lattice, are emerging as key modulators of the microtubule cytoskeleton in different model systems. In this review, we provide an integrative view on the latest research demonstrating the key role of spastin in neurons, specifically in the context of axonal cell biology. We focus on the function of spastin in the regulation of microtubule organization, and axonal transport, that underlie its importance in the intricate control of axon growth, branching and regeneration.
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Affiliation(s)
- Ana Catarina Costa
- Nerve Regeneration Group, Instituto de Biologia Molecular e Celular (IBMC), Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Graduate Program in Molecular and Cell Biology, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- *Correspondence: Ana Catarina Costa, ; Monica Mendes Sousa,
| | - Monica Mendes Sousa
- Nerve Regeneration Group, Instituto de Biologia Molecular e Celular (IBMC), Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- *Correspondence: Ana Catarina Costa, ; Monica Mendes Sousa,
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Chen L, Wang H, Cha S, Li J, Zhang J, Wu J, Guo G, Zhang J. Phosphorylation of Spastin Promotes the Surface Delivery and Synaptic Function of AMPA Receptors. Front Cell Neurosci 2022; 16:809934. [PMID: 35418834 PMCID: PMC8995424 DOI: 10.3389/fncel.2022.809934] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 03/07/2022] [Indexed: 12/14/2022] Open
Abstract
Synaptic plasticity is essential for cognitive functions such as learning and memory. One of the mechanisms involved in synaptic plasticity is the dynamic delivery of AMPA receptors (AMPARs) in and out of synapses. Mutations of SPAST, which encodes SPASTIN, a microtubule-severing protein, are considered the most common cause of hereditary spastic paraparesis (HSP). In some cases, patients with HSP also manifest cognitive impairment. In addition, mice with Spastin depletion exhibit working and associative memory deficits and reduced AMPAR levels. However, the exact effect and molecular mechanism of Spastin on AMPARs trafficking has remained unclear. Here, we report that Spastin interacts with AMPAR, and phosphorylation of Spastin enhances its interaction with AMPAR subunit GluA2. Further study shows that phosphorylation of Spastin can increase AMPAR GluA2 surface expression and the amplitude and frequency of miniature excitatory synaptic currents (mEPSC) in cultured hippocampal neurons. Moreover, phosphorylation of Spastin at Ser210 is crucial for GluA2 surface expression. Phosphorylation of Spastin K353A, which obliterates microtubule-severing activity, also promotes AMPAR GluA2 subunit trafficking to the surface and increases the amplitude and frequency of mEPSCs in cultured neurons. Taken together, our data demonstrate that Spastin phosphorylation promotes the surface delivery of the AMPAR GluA2 subunit independent of microtubule dynamics.
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Affiliation(s)
- Li Chen
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Hanjie Wang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Shuhan Cha
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiong Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiaqi Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiaming Wu
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Guoqing Guo
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- *Correspondence: Guoqing Guo Jifeng Zhang
| | - Jifeng Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- *Correspondence: Guoqing Guo Jifeng Zhang
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8
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Improvement in the Blood Urea Nitrogen and Serum Creatinine Using New Cultivation of Cordyceps militaris. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:4321298. [PMID: 35368765 PMCID: PMC8967507 DOI: 10.1155/2022/4321298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/31/2022] [Indexed: 11/17/2022]
Abstract
Background Chronic kidney disease (CKD) is a critical public health issue with a huge financial burden for both patients and society worldwide. Unfortunately, there are currently no efficacious therapies to prevent or delay the progression of end-stage renal disease (ESRD). Traditional Chinese medicine practices have shown that Cordyceps militaris (C. militaris) mycelia have a variety of pharmacologically useful properties, including antitumor, immunomodulation, and hepatoprotection. However, the effect of mycelial C. militaris on CKD remains unclear. Methods Here, we investigated the effects of C. militaris mycelia on mice with CKD using four types of media: HKS, HKS with vitamin A (HKS + A), CM, and CM with vitamin A (CM + A). Results The results at day 10 revealed that the levels of blood urea nitrogen (BUN) were significantly lower in the HKS (41%), HKS + A (41%), and CM + A (34%) groups compared with those in the corresponding control groups (nephrectomic mice). The level of serum creatinine in the HKS + A group decreased by 35% at day 10, whereas the levels in the HKS and CM + A groups decreased only by 14% and 13%, respectively, on day 30. Taken together, this is the first report using four new media (HKS, HKS + A, CM, and CM + A medium) for C. militaris mycelia. Each medium of mycelial C. militaris on CKD exhibits specific effect on BUN, serum creatinine, body weight, total protein, and uric acid. Conclusions Taken together, this is the first report using four new media (HKS, HKS + A, CM, and CM + A medium) for C. militaris mycelia. Each medium of mycelial C. militaris on CKD exhibits specific effects on BUN, serum creatinine, body weight, total protein, and uric acid. We concluded that treatment with C. militaris mycelia cultured in HKS or CM + A medium could potentially prevent the deterioration of kidney function in mice with CKD.
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Zou J, Cai Z, Liang Z, Liang Y, Zhang G, Yang J, Zhang Y, Lin H, Tan M. Different fusion tags affect the activity of ubiquitin overexpression on spastin protein stability. Eur J Histochem 2021; 65. [PMID: 34873900 PMCID: PMC8678624 DOI: 10.4081/ejh.2021.3352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 11/23/2021] [Indexed: 11/23/2022] Open
Abstract
Spastin is one of the proteins which lead to hereditary spastic paraplegia (HSP), whose dysfunction towards microtubule severing and membrane transporting is critically important. The present study is to elucidate the mechanisms of the protein stability regulation of spastin. The ubiquitin encoding plasmids were transfected into COS-7 cells with different fusion tags including Green Fluorescent Protein (GFP), mCherry and Flag. The expression level of spastin was detected, microtubule severing activity and neurite outgrowth were quantified. The data showed that ubiquitin overexpression significantly induced the decreased expression of spastin, suppressed the activity of microtubule severing in COS-7 cells and inhibited the promoting effect on neurite outgrowth in cultured hippocampal neurons. Furthermore, when modulating the overexpression experiments of ubiquitin, it was found that relatively small tag like Flag, but not large tags such as GFP or mCherry fused with ubiquitin, retained the activity on spastin stability. The present study investigated the effects of small/large tags addition to ubiquitin and the novel mechanisms of post-transcriptional modifications of spastin on regulating neurite outgrowth, in the attempt to experimentally elucidate the mechanisms that control the level or stability of spastin in hereditary spastic paraplegia.
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Affiliation(s)
- Jianyu Zou
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Zhenbin Cai
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Zhi Liang
- Department of Orthopaedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen.
| | - Yaozhong Liang
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Guowei Zhang
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Jie Yang
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Yunlong Zhang
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Hongsheng Lin
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
| | - Minghui Tan
- Department of Orthopaedics, The First Affiliated Hospital of Jinan University, Guangzhou.
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10
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Liu Q, Zhang G, Ji Z, Lin H. Molecular and cellular mechanisms of spastin in neural development and disease (Review). Int J Mol Med 2021; 48:218. [PMID: 34664680 PMCID: PMC8547542 DOI: 10.3892/ijmm.2021.5051] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/29/2021] [Indexed: 12/26/2022] Open
Abstract
Spastin is a microtubule (MT)‑severing enzyme identified from mutations of hereditary spastic paraplegia in 1999 and extensive studies indicate its vital role in various cellular activities. In the past two decades, efforts have been made to understand the underlying molecular mechanisms of how spastin is linked to neural development and disease. Recent studies on spastin have unraveled the mechanistic processes of its MT‑severing activity and revealed that spastin acts as an MT amplifier to mediate its remodeling, thus providing valuable insight into the molecular roles of spastin under physiological conditions. In addition, recent research has revealed multiple novel molecular mechanisms of spastin in cellular biological pathways, including endoplasmic reticulum shaping, calcium trafficking, fatty acid trafficking, as well as endosomal fission and trafficking. These processes are closely involved in axonal and dendritic development and maintenance. The current review presents recent biological advances regarding the molecular mechanisms of spastin at the cellular level and provides insight into how it affects neural development and disease.
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Affiliation(s)
- Qiuling Liu
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Guowei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Zhisheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Hongsheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
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11
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Ma L. PHOSPHOCREATINE IMPROVES MUSCLE MICROCIRCULATION DURING EXERCISE. REV BRAS MED ESPORTE 2021. [DOI: 10.1590/1517-8692202127082021_0344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ABSTRACT Introduction: Phosphate (CP) its biosynthesis begins with the kidney. Glycocianine was synthesized from glycocianine, then methylated in the liver, and finally formed in each tissue. Objective: To study the effects of phosphatic acid in exercise training. Methods: This paper uses 50 pure male mice, 2 month old, weight at 22 ± 3 g, and mice per day, 5 minutes each time. After exercise training, dry dry with a towel and blow it with a hair dryer, and move it to the end of each other. Results: The average time of motion B mouse to give phosphate creatine is significantly longer than the average time of the non-administration of the A group, and the motion time is prolonged to extend 23.20%. Phosphate has improved motor endurance and promotes improvement in muscle microcirculation during exercise. Conclusions: Motion can be used to improve the maximum aerobic capacity of exercise in motion. Level of evidence II; Therapeutic studies - investigation of treatment results.
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12
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Zhang G, Li S, Cheng KW, Chou TF. AAA ATPases as therapeutic targets: Structure, functions, and small-molecule inhibitors. Eur J Med Chem 2021; 219:113446. [PMID: 33873056 PMCID: PMC8165034 DOI: 10.1016/j.ejmech.2021.113446] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 03/21/2021] [Accepted: 03/30/2021] [Indexed: 01/07/2023]
Abstract
ATPases Associated with Diverse Cellular Activity (AAA ATPase) are essential enzymes found in all organisms. They are involved in various processes such as DNA replication, protein degradation, membrane fusion, microtubule serving, peroxisome biogenesis, signal transduction, and the regulation of gene expression. Due to the importance of AAA ATPases, several researchers identified and developed small-molecule inhibitors against these enzymes. We discuss six AAA ATPases that are potential drug targets and have well-developed inhibitors. We compare available structures that suggest significant differences of the ATP binding pockets among the AAA ATPases with or without ligand. The distances from ADP to the His20 in the His-Ser-His motif and the Arg finger (Arg353 or Arg378) in both RUVBL1/2 complex structures bound with or without ADP have significant differences, suggesting dramatically different interactions of the binding site with ADP. Taken together, the inhibitors of six well-studied AAA ATPases and their structural information suggest further development of specific AAA ATPase inhibitors due to difference in their structures. Future chemical biology coupled with proteomic approaches could be employed to develop variant specific, complex specific, and pathway specific inhibitors or activators for AAA ATPase proteins.
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Affiliation(s)
- Gang Zhang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, United States.
| | - Shan Li
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, United States
| | - Kai-Wen Cheng
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, United States
| | - Tsui-Fen Chou
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, United States.
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13
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Sardina F, Pisciottani A, Ferrara M, Valente D, Casella M, Crescenzi M, Peschiaroli A, Casali C, Soddu S, Grierson AJ, Rinaldo C. Spastin recovery in hereditary spastic paraplegia by preventing neddylation-dependent degradation. Life Sci Alliance 2020; 3:3/12/e202000799. [PMID: 33106322 PMCID: PMC7652396 DOI: 10.26508/lsa.202000799] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 01/11/2023] Open
Abstract
Hereditary Spastic Paraplegia (HSP) is a neurodegenerative disease most commonly caused by autosomal dominant mutations in the SPG4 gene encoding the microtubule-severing protein spastin. We hypothesise that SPG4-HSP is attributable to reduced spastin function because of haploinsufficiency; thus, therapeutic approaches which elevate levels of the wild-type spastin allele may be an effective therapy. However, until now, how spastin levels are regulated is largely unknown. Here, we show that the kinase HIPK2 regulates spastin protein levels in proliferating cells, in differentiated neurons and in vivo. Our work reveals that HIPK2-mediated phosphorylation of spastin at S268 inhibits spastin K48-poly-ubiquitination at K554 and prevents its neddylation-dependent proteasomal degradation. In a spastin RNAi neuronal cell model, overexpression of HIPK2, or inhibition of neddylation, restores spastin levels and rescues neurite defects. Notably, we demonstrate that spastin levels can be restored pharmacologically by inhibiting its neddylation-mediated degradation in neurons derived from a spastin mouse model of HSP and in patient-derived cells, thus revealing novel therapeutic targets for the treatment of SPG4-HSP.
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Affiliation(s)
- Francesca Sardina
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, Rome, Italy
| | - Alessandra Pisciottani
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, Rome, Italy
| | - Manuela Ferrara
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, Rome, Italy
| | - Davide Valente
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, Rome, Italy.,Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | | | - Marco Crescenzi
- Core Facilities, Italian National Institute of Health, Rome, Italy
| | | | - Carlo Casali
- Department of Medico-Surgical Sciences and Biotechnologies, University of Rome Sapienza, Latina, Italy
| | - Silvia Soddu
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | - Andrew J Grierson
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Cinzia Rinaldo
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, Rome, Italy .,Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
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14
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Ji ZS, Liu QL, Zhang JF, Yang YH, Li J, Zhang GW, Tan MH, Lin HS, Guo GQ. SUMOylation of spastin promotes the internalization of GluA1 and regulates dendritic spine morphology by targeting microtubule dynamics. Neurobiol Dis 2020; 146:105133. [PMID: 33049318 DOI: 10.1016/j.nbd.2020.105133] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/24/2020] [Accepted: 10/06/2020] [Indexed: 10/23/2022] Open
Abstract
Dendritic spines are specialized structures involved in neuronal processes on which excitatory synaptic contact occurs. The microtubule cytoskeleton is vital for maintaining spine morphology and mature synapses. Spastin is related to microtubule-severing proteases and is involved in synaptic bouton formation. However, it is not yet known if spastin can be modified by Small Ubiquitin-like Modifier (SUMO) or how this modification regulates dendritic spines. Spastin was shown to be SUMOylated at K427, and its deSUMOylation promoted microtubule stability. In addition, SUMOylation of spastin was shown to affect signalling pathways associated with long term synaptic depression. SUMOylated spastin promoted the development of dendrites and dendritic spines. Moreover, SUMOylated spastin regulated endocytosis and affected the transport of the AMPA receptor, GluA1. Our findings suggest that SUMOylation of spastin promotes GluA1 internalization and regulates dendritic spine morphology through targeting of microtubule dynamics.
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Affiliation(s)
- Zhi-Sheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Qiu-Ling Liu
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Ji-Feng Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Yu-Hao Yang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Jiong Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Guo-Wei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China
| | - Ming-Hui Tan
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China.
| | - Hong-Sheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China.
| | - Guo-Qing Guo
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, No.601 West Huangpu Avenue, Tianhe, Guangzhou 510630, China.
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15
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Haas J, Bloesel D, Bacher S, Kracht M, Schmitz ML. Chromatin Targeting of HIPK2 Leads to Acetylation-Dependent Chromatin Decondensation. Front Cell Dev Biol 2020; 8:852. [PMID: 32984337 PMCID: PMC7490299 DOI: 10.3389/fcell.2020.00852] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 08/10/2020] [Indexed: 11/13/2022] Open
Abstract
The protein kinase homeodomain-interacting protein kinase 2 (HIPK2) plays an important role in development and in the response to external cues. The kinase associates with an exceptionally large number of different transcription factors and chromatin regulatory proteins to direct distinct gene expression programs. In order to investigate the function of HIPK2 for chromatin compaction, HIPK2 was fused to the DNA-binding domains of Gal4 or LacI, thus allowing its specific targeting to binding sites for these transcription factors that were integrated in specific chromosome loci. Tethering of HIPK2 resulted in strong decompaction of euchromatic and heterochromatic areas. HIPK2-mediated heterochromatin decondensation started already 4 h after its chromatin association and required the functionality of its SUMO-interacting motif. This process was paralleled by disappearance of the repressive H3K27me3 chromatin mark, recruitment of the acetyltransferases CBP and p300 and increased histone acetylation at H3K18 and H4K5. HIPK2-mediated chromatin decompaction was strongly inhibited in the presence of a CBP/p300 inhibitor and completely blocked by the BET inhibitor JQ1, consistent with a causative role of acetylations for this process. Chromatin tethering of HIPK2 had only a minor effect on basal transcription, while it strongly boosted estrogen-triggered gene expression by acting as a transcriptional cofactor.
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Affiliation(s)
- Jana Haas
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Daniel Bloesel
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Susanne Bacher
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
| | - Michael Kracht
- Member of the German Center for Lung Research, Giessen, Germany.,Rudolf-Buchheim-Institute of Pharmacology, Justus-Liebig-University, Giessen, Germany
| | - M Lienhard Schmitz
- Institute of Biochemistry, Justus-Liebig-University, Giessen, Germany.,Member of the German Center for Lung Research, Giessen, Germany
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16
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Sardina F, Monteonofrio L, Ferrara M, Magi F, Soddu S, Rinaldo C. HIPK2 Is Required for Midbody Remnant Removal Through Autophagy-Mediated Degradation. Front Cell Dev Biol 2020; 8:572094. [PMID: 33043004 PMCID: PMC7525647 DOI: 10.3389/fcell.2020.572094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/18/2020] [Indexed: 01/09/2023] Open
Abstract
At the end of abscission, the residual midbody forms the so-called midbody remnant (MBR), a platform affecting cell fate with emerging key role in differentiation, development, and tumorigenicity. Depending on cell type and pathophysiological context, MBRs undergo different outcomes: they can be retained, released, internalized by nearby cells, or removed through autophagy-mediated degradation. Although mechanisms underlying MBR formation, positioning, and processing have been recently identified, their regulation is still largely unknown. Here, we report that the multifunctional kinase HIPK2 regulates MBR processing contributing to MBR removal. In the process of studying the role of HIPK2 in abscission, we observed that, in addition to cytokinesis failure, HIPK2 depletion leads to significant accumulation of MBRs. In particular, we detected comparable accumulation of MBRs after HIPK2 depletion or treatment with the autophagic inhibitor chloroquine. In contrast, single depletion of the two independent HIPK2 abscission targets, extrachromosomal histone H2B and severing enzyme Spastin, only marginally increased MBR retention, suggesting that MBR accumulation is not just linked to cytokinesis failure. We found that HIPK2 depletion leads to (i) increased levels of CEP55, a key effector of both midbody formation and MBR degradation; (ii) decreased levels of the selective autophagy receptors NBR1 and p62/SQSTM1; and (iii) impaired autophagic flux. These data suggest that HIPK2 contributes to MBR processing by regulating its autophagy-mediated degradation.
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Affiliation(s)
- Francesca Sardina
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University of Rome, Rome, Italy
| | - Laura Monteonofrio
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Manuela Ferrara
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University of Rome, Rome, Italy
| | - Fiorenza Magi
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Silvia Soddu
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Cinzia Rinaldo
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University of Rome, Rome, Italy.,Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS Regina Elena National Cancer Institute, Rome, Italy
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17
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An Alternative Splice Variant of HIPK2 with Intron Retention Contributes to Cytokinesis. Cells 2020; 9:cells9020484. [PMID: 32093146 PMCID: PMC7072727 DOI: 10.3390/cells9020484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/10/2020] [Accepted: 02/17/2020] [Indexed: 12/27/2022] Open
Abstract
HIPK2 is a DYRK-like kinase involved in cellular stress response pathways, development, and cell division. Two alternative splice variants of HIPK2, HIPK2-FL and HIPK2-Δe8, have been previously identified as having different protein stability but similar functional activity in the stress response. Here, we describe one additional HIPK2 splice variant with a distinct subcellular distribution and functional activity in cytokinesis. This novel splice variant lacks the last two exons and retains intron13 with a stop codon after 89 bp of the intron, generating a short isoform, HIPK2-S, that is detectable by 2D Western blots. RT-PCR analyses of tissue arrays and tumor samples show that HIPK2-FL and HIPK2-S are expressed in normal human tissues in a tissue-dependent manner and differentially expressed in human colorectal and pancreatic cancers. Gain- and loss-of-function experiments showed that in contrast to HIPK2-FL, HIPK2-S has a diffuse, non-speckled distribution and is not involved in the DNA damage response. Rather, we found that HIPK2-S, but not HIPK2-FL, localizes at the intercellular bridge, where it phosphorylates histone H2B and spastin, both required for faithful cell division. Altogether, these data show that distinct human HIPK2 splice variants are involved in distinct HIPK2-regulated functions like stress response and cytokinesis.
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18
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Monteonofrio L, Valente D, Rinaldo C, Soddu S. Extrachromosomal Histone H2B Contributes to the Formation of the Abscission Site for Cell Division. Cells 2019; 8:cells8111391. [PMID: 31694230 PMCID: PMC6912571 DOI: 10.3390/cells8111391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/25/2019] [Accepted: 10/31/2019] [Indexed: 12/13/2022] Open
Abstract
Histones are constitutive components of nucleosomes and key regulators of chromatin structure. We previously observed that an extrachromosomal histone H2B (ecH2B) localizes at the intercellular bridge (ICB) connecting the two daughter cells during cytokinesis independently of DNA and RNA. Here, we show that ecH2B binds and colocalizes with CHMP4B, a key component of the ESCRT-III machinery responsible for abscission, the final step of cell division. Abscission requires the formation of an abscission site at the ICB where the ESCRT-III complex organizes into narrowing cortical helices that drive the physical separation of sibling cells. ecH2B depletion does not prevent membrane cleavage rather results in abscission delay and accumulation of abnormally long and thin ICBs. In the absence of ecH2B, CHMP4B and other components of the fission machinery, such as IST1 and Spastin, are recruited to the ICB and localize at the midbody. However, in the late stage of abscission, these fission factors fail to re-localize at the periphery of the midbody and the abscission site fails to form. These results show that extrachromosomal activity of histone H2B is required in the formation of the abscission site and the proper localization of the fission machinery.
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Affiliation(s)
- Laura Monteonofrio
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, 00144 Rome, Italy; (D.V.); (C.R.)
- Correspondence: (L.M.); (S.S.); Tel.: +1-(443)-410-9571 (L.M.); +39-065266-2492 (S.S.)
| | - Davide Valente
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, 00144 Rome, Italy; (D.V.); (C.R.)
| | - Cinzia Rinaldo
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, 00144 Rome, Italy; (D.V.); (C.R.)
- Institutes of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Sapienza University, 00185 Rome, Italy
| | - Silvia Soddu
- Unit of Cellular Networks and Molecular Therapeutic Targets, IRCCS-Regina Elena National Cancer Institute, 00144 Rome, Italy; (D.V.); (C.R.)
- Correspondence: (L.M.); (S.S.); Tel.: +1-(443)-410-9571 (L.M.); +39-065266-2492 (S.S.)
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