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Omoda A, Matsumoto K, Yoshino KI, Tachibana M, Tsuboi T, Torii M, Ishino T, Iriko H. Skeleton binding protein 1 localizes to the Maurer's cleft and interacts with PfHSP70-1 and PfHSP70-x in Plasmodium falciparum gametocyte-infected erythrocytes. Parasitol Int 2024; 100:102864. [PMID: 38331312 DOI: 10.1016/j.parint.2024.102864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/01/2024] [Accepted: 02/03/2024] [Indexed: 02/10/2024]
Abstract
Plasmodium falciparum accounts for the majority of malaria deaths, due to pathology provoked by the ability of infected erythrocytes to adhere to vascular endothelium within deep tissues. The parasite recognizes endothelium by trafficking and displaying protein ligands on the surface of asexual stage infected erythrocytes, such as members of the large family of pathogenic proteins, P. falciparum erythrocyte membrane protein 1 (PfEMP1). Parasite-encoded skeleton binding protein 1 (SBP1) plays an important role in the transport of these binding-related surface proteins, via cleft-like membranous structures termed Maurer's clefts, which are present within the cytoplasm of infected erythrocytes. Erythrocytes infected with gametocyte stages accumulate in the extravascular compartment of bone marrow; and it was suggested that their surface-expressed adhesion molecule profile and protein trafficking mechanisms might differ from those in asexual stage parasites. Protein trafficking mechanisms via Maurer's clefts have been well investigated in asexual stage parasite-infected erythrocytes; but little is known regarding the gametocyte stages. In this study, we characterized SBP1 during gametocyte maturation and demonstrated that SBP1 is expressed and localizes to dot-like Maurer's cleft structures in the cytoplasm of gametocyte-infected erythrocytes. Co-immunoprecipitation and mass spectrometry assays indicated that SBP1 interacts with the molecular chaperones PfHSP70-1 and PfHSP70-x. Localization analysis suggested that some PfHSP70-1 and/or PfHSP70-x localize in a dot-like pattern within the cytoplasm of immature gametocyte-infected erythrocytes. These findings suggest that SBP1 may interact with HSP70 chaperones in the infected erythrocyte cytoplasm during the immature gametocyte stages.
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Affiliation(s)
- Ayaka Omoda
- Division of Global Infectious Diseases, Department of Public Health, Graduate School of Health Sciences, Kobe University, Kobe, Hyogo, Japan
| | - Konomi Matsumoto
- Faculty of Health Sciences, Kobe University School of Medicine, Kobe, Hyogo, Japan
| | | | - Mayumi Tachibana
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Ehime, Japan
| | - Takafumi Tsuboi
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Motomi Torii
- Division of Global Infectious Diseases, Department of Public Health, Graduate School of Health Sciences, Kobe University, Kobe, Hyogo, Japan; Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Ehime, Japan
| | - Tomoko Ishino
- Department of Parasitology and Tropical Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Hideyuki Iriko
- Division of Global Infectious Diseases, Department of Public Health, Graduate School of Health Sciences, Kobe University, Kobe, Hyogo, Japan; Faculty of Health Sciences, Kobe University School of Medicine, Kobe, Hyogo, Japan.
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Barker E, Milburn AE, Helassa N, Hammond DE, Sanchez-Soriano N, Morgan A, Barclay JW. Proximity labelling reveals effects of disease-causing mutation on the DNAJC5/cysteine string protein α interactome. Biochem J 2024; 481:BCJ20230319. [PMID: 38193346 PMCID: PMC10903463 DOI: 10.1042/bcj20230319] [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: 07/29/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 01/10/2024]
Abstract
Cysteine string protein α (CSPα), also known as DNAJC5, is a member of the DnaJ/Hsp40 family of co-chaperones. The name derives from a cysteine-rich domain, palmitoylation of which enables localization to intracellular membranes, notably neuronal synaptic vesicles. Mutations in the DNAJC5 gene that encodes CSPα cause autosomal dominant, adult-onset neuronal ceroid lipofuscinosis (ANCL), a rare neurodegenerative disease. As null mutations in CSP-encoding genes in flies, worms and mice similarly result in neurodegeneration, CSP is evidently an evolutionarily conserved neuroprotective protein. However, the client proteins that CSP chaperones to prevent neurodegeneration remain unclear. Traditional methods for identifying protein-protein interactions such as yeast 2-hybrid and affinity purification approaches are poorly suited to CSP, due to its requirement for membrane anchoring and its tendency to aggregate after cell lysis. Therefore, we employed proximity labelling, which enables identification of interacting proteins in situ in living cells via biotinylation. Neuroendocrine PC12 cell lines stably expressing wild type or L115R ANCL mutant CSP constructs fused to miniTurbo were generated; then the biotinylated proteomes were analysed by liquid chromatographymass spectrometry (LCMS) and validated by western blotting. This confirmed several known CSP-interacting proteins, such as Hsc70 and SNAP-25, but also revealed novel binding proteins, including STXBP1/Munc18-1. Interestingly, some protein interactions (such as Hsc70) were unaffected by the L115R mutation, whereas others (including SNAP-25 and STXBP1/Munc18-1) were inhibited. These results define the CSP interactome in a neuronal model cell line and reveal interactions that are affected by ANCL mutation and hence may contribute to the neurodegeneration seen in patients.
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Affiliation(s)
- Eleanor Barker
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Amy E. Milburn
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Nordine Helassa
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Dean E. Hammond
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Natalia Sanchez-Soriano
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Alan Morgan
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
| | - Jeff W. Barclay
- Department of Biochemistry, Cell and Systems Biology, ISMIB, University of Liverpool, Liverpool, U.K
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3
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Silvestro S, Raffaele I, Mazzon E. Modulating Stress Proteins in Response to Therapeutic Interventions for Parkinson's Disease. Int J Mol Sci 2023; 24:16233. [PMID: 38003423 PMCID: PMC10671288 DOI: 10.3390/ijms242216233] [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: 10/03/2023] [Revised: 11/03/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative illness characterized by the degeneration of dopaminergic neurons in the substantia nigra, resulting in motor symptoms and without debilitating motors. A hallmark of this condition is the accumulation of misfolded proteins, a phenomenon that drives disease progression. In this regard, heat shock proteins (HSPs) play a central role in the cellular response to stress, shielding cells from damage induced by protein aggregates and oxidative stress. As a result, researchers have become increasingly interested in modulating these proteins through pharmacological and non-pharmacological therapeutic interventions. This review aims to provide an overview of the preclinical experiments performed over the last decade in this research field. Specifically, it focuses on preclinical studies that center on the modulation of stress proteins for the treatment potential of PD. The findings display promise in targeting HSPs to ameliorate PD outcomes. Despite the complexity of HSPs and their co-chaperones, proteins such as HSP70, HSP27, HSP90, and glucose-regulated protein-78 (GRP78) may be efficacious in slowing or preventing disease progression. Nevertheless, clinical validation is essential to confirm the safety and effectiveness of these preclinical approaches.
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Affiliation(s)
| | | | - Emanuela Mazzon
- IRCCS Centro Neurolesi Bonino Pulejo, Via Provinciale Palermo, Contrada Casazza, 98124 Messina, Italy; (S.S.); (I.R.)
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Venediktov AA, Bushueva OY, Kudryavtseva VA, Kuzmin EA, Moiseeva AV, Baldycheva A, Meglinski I, Piavchenko GA. Closest horizons of Hsp70 engagement to manage neurodegeneration. Front Mol Neurosci 2023; 16:1230436. [PMID: 37795273 PMCID: PMC10546621 DOI: 10.3389/fnmol.2023.1230436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/18/2023] [Indexed: 10/06/2023] Open
Abstract
Our review seeks to elucidate the current state-of-the-art in studies of 70-kilodalton-weighed heat shock proteins (Hsp70) in neurodegenerative diseases (NDs). The family has already been shown to play a crucial role in pathological aggregation for a wide spectrum of brain pathologies. However, a slender boundary between a big body of fundamental data and its implementation has only recently been crossed. Currently, we are witnessing an anticipated advancement in the domain with dozens of studies published every month. In this review, we briefly summarize scattered results regarding the role of Hsp70 in the most common NDs including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). We also bridge translational studies and clinical trials to portray the output for medical practice. Available options to regulate Hsp70 activity in NDs are outlined, too.
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Affiliation(s)
- Artem A. Venediktov
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Olga Yu Bushueva
- Laboratory of Genomic Research, Research Institute for Genetic and Molecular Epidemiology, Kursk State Medical University, Kursk, Russia
| | - Varvara A. Kudryavtseva
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Egor A. Kuzmin
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Aleksandra V. Moiseeva
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Anna Baldycheva
- STEMM Laboratory, University of Exeter, Exeter, United Kingdom
| | - Igor Meglinski
- Department of Physics, University of Oulu, Oulu, Finland
- College of Engineering and Physical Sciences, Aston University, Birmingham, United Kingdom
| | - Gennadii A. Piavchenko
- Department of Human Anatomy and Histology, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
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Wei Y, Awan MUN, Bai L, Bai J. The function of Golgi apparatus in LRRK2-associated Parkinson's disease. Front Mol Neurosci 2023; 16:1097633. [PMID: 36896008 PMCID: PMC9989030 DOI: 10.3389/fnmol.2023.1097633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 02/06/2023] [Indexed: 02/25/2023] Open
Abstract
Parkinson's disease (PD) is a chronic neurodegenerative disease associated with the intracellular organelles. Leucine-rich repeat kinase 2 (LRRK2) is a large multi-structural domain protein, and mutation in LRRK2 is associated with PD. LRRK2 regulates intracellular vesicle transport and function of organelles, including Golgi and lysosome. LRRK2 phosphorylates a group of Rab GTPases, including Rab29, Rab8, and Rab10. Rab29 acts in a common pathway with LRRK2. Rab29 has been shown to recruit LRRK2 to the Golgi complex (GC) to stimulate LRRK2 activity and alter the Golgi apparatus (GA). Interaction between LRRK2 and Vacuolar protein sorting protein 52 (VPS52), a subunit of the Golgi-associated retrograde protein (GARP) complex, mediates the function of intracellular soma trans-Golgi network (TGN) transport. VPS52 also interacts with Rab29. Knockdown of VPS52 leads to the loss of LRRK2/Rab29 transported to the TGN. Rab29, LRRK2, and VPS52 work together to regulate functions of the GA, which is associated with PD. We highlight recent advances in the roles of LRRK2, Rabs, VPS52, and other molecules, such as Cyclin-dependent kinase 5 (CDK5) and protein kinase C (PKC) in the GA, and discuss their possible association with the pathological mechanisms of PD.
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Affiliation(s)
- Yonghang Wei
- Laboratory of Molecular Neurobiology, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Maher Un Nisa Awan
- Laboratory of Molecular Neurobiology, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Liping Bai
- Laboratory of Molecular Neurobiology, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Jie Bai
- Laboratory of Molecular Neurobiology, Medical School, Kunming University of Science and Technology, Kunming, China
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The bacterial toxin ExoU requires a host trafficking chaperone for transportation and to induce necrosis. Nat Commun 2021; 12:4024. [PMID: 34188051 PMCID: PMC8241856 DOI: 10.1038/s41467-021-24337-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 06/11/2021] [Indexed: 12/17/2022] Open
Abstract
Pseudomonas aeruginosa can cause nosocomial infections, especially in ventilated or cystic fibrosis patients. Highly pathogenic isolates express the phospholipase ExoU, an effector of the type III secretion system that acts on plasma membrane lipids, causing membrane rupture and host cell necrosis. Here, we use a genome-wide screen to discover that ExoU requires DNAJC5, a host chaperone, for its necrotic activity. DNAJC5 is known to participate in an unconventional secretory pathway for misfolded proteins involving anterograde vesicular trafficking. We show that DNAJC5-deficient human cells, or Drosophila flies knocked-down for the DNAJC5 orthologue, are largely resistant to ExoU-dependent virulence. ExoU colocalizes with DNAJC5-positive vesicles in the host cytoplasm. DNAJC5 mutations preventing vesicle trafficking (previously identified in adult neuronal ceroid lipofuscinosis, a human congenital disease) inhibit ExoU-dependent cell lysis. Our results suggest that, once injected into the host cytoplasm, ExoU docks to DNAJC5-positive secretory vesicles to reach the plasma membrane, where it can exert its phospholipase activity Phospholipase ExoU from Pseudomonas aeruginosa acts on plasma membrane lipids in infected cells, causing membrane rupture and host cell necrosis. Here, Deruelle et al. show that once injected into the host cytoplasm, ExoU requires a host chaperone found on secretory vesicles to reach the plasma membrane and exerts its phospholipase activity.
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Melland H, Carr EM, Gordon SL. Disorders of synaptic vesicle fusion machinery. J Neurochem 2020; 157:130-164. [PMID: 32916768 DOI: 10.1111/jnc.15181] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 12/11/2022]
Abstract
The revolution in genetic technology has ushered in a new age for our understanding of the underlying causes of neurodevelopmental, neuromuscular and neurodegenerative disorders, revealing that the presynaptic machinery governing synaptic vesicle fusion is compromised in many of these neurological disorders. This builds upon decades of research showing that disturbance to neurotransmitter release via toxins can cause acute neurological dysfunction. In this review, we focus on disorders of synaptic vesicle fusion caused either by toxic insult to the presynapse or alterations to genes encoding the key proteins that control and regulate fusion: the SNARE proteins (synaptobrevin, syntaxin-1 and SNAP-25), Munc18, Munc13, synaptotagmin, complexin, CSPα, α-synuclein, PRRT2 and tomosyn. We discuss the roles of these proteins and the cellular and molecular mechanisms underpinning neurological deficits in these disorders.
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Affiliation(s)
- Holly Melland
- The Florey Institute of Neuroscience and Mental Health, Melbourne Dementia Research Centre, The University of Melbourne, Melbourne, Vic., Australia
| | - Elysa M Carr
- The Florey Institute of Neuroscience and Mental Health, Melbourne Dementia Research Centre, The University of Melbourne, Melbourne, Vic., Australia
| | - Sarah L Gordon
- The Florey Institute of Neuroscience and Mental Health, Melbourne Dementia Research Centre, The University of Melbourne, Melbourne, Vic., Australia
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8
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Gundersen CB. Cysteine string proteins. Prog Neurobiol 2020; 188:101758. [DOI: 10.1016/j.pneurobio.2020.101758] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/06/2020] [Accepted: 01/13/2020] [Indexed: 12/17/2022]
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9
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Fluoxetine Suppresses Glutamate- and GABA-Mediated Neurotransmission by Altering SNARE Complex. Int J Mol Sci 2019; 20:ijms20174247. [PMID: 31480244 PMCID: PMC6747167 DOI: 10.3390/ijms20174247] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/22/2019] [Accepted: 08/27/2019] [Indexed: 12/21/2022] Open
Abstract
Major depressive disorder is one of the most common neuropsychiatric disorders worldwide. The treatment of choice that shows good efficacy in mood stabilization is based on selective serotonin reuptake inhibitors (SSRIs). Their primary mechanism of action is considered to be the increased synaptic concentration of serotonin through blockade of the serotonin transporter (SERT). In this study, we described an alternative mode of action of fluoxetine (FLX), which is a representative member of the SSRI class of antidepressants. We observed that FLX robustly decreases both glutamatergic and gamma-Aminobutyric acid (GABA)-ergic synaptic release in a SERT-independent manner. Moreover, we showed that this effect may stem from the ability of FLX to change the levels of main components of the SNARE (solubile N-ethylmaleimide-sensitive factor attachment protein receptor) complex. Our data suggest that this downregulation of SNARE fusion machinery involves diminished activity of protein kinase C (PKC) due to FLX-induced blockade of P/Q type of voltage-gated calcium channels (VGCCs). Taken together, by virtue of its inhibition at SERT, fluoxetine increases extracellular serotonin levels; however, at the same time, by reducing SNARE complex function, this antidepressant reduces glutamate and GABA release.
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Velasco L, Dublang L, Moro F, Muga A. The Complex Phosphorylation Patterns that Regulate the Activity of Hsp70 and Its Cochaperones. Int J Mol Sci 2019; 20:ijms20174122. [PMID: 31450862 PMCID: PMC6747476 DOI: 10.3390/ijms20174122] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 08/21/2019] [Accepted: 08/22/2019] [Indexed: 12/26/2022] Open
Abstract
Proteins must fold into their native structure and maintain it during their lifespan to display the desired activity. To ensure proper folding and stability, and avoid generation of misfolded conformations that can be potentially cytotoxic, cells synthesize a wide variety of molecular chaperones that assist folding of other proteins and avoid their aggregation, which unfortunately is unavoidable under acute stress conditions. A protein machinery in metazoa, composed of representatives of the Hsp70, Hsp40, and Hsp110 chaperone families, can reactivate protein aggregates. We revised herein the phosphorylation sites found so far in members of these chaperone families and the functional consequences associated with some of them. We also discuss how phosphorylation might regulate the chaperone activity and the interaction of human Hsp70 with its accessory and client proteins. Finally, we present the information that would be necessary to decrypt the effect that post-translational modifications, and especially phosphorylation, could have on the biological activity of the Hsp70 system, known as the “chaperone code”.
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Affiliation(s)
- Lorea Velasco
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain
| | - Leire Dublang
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain
| | - Fernando Moro
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain.
| | - Arturo Muga
- Biofisika Institute (UPV/EHU, CSIC) and Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, 48940 Leioa, Spain.
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Hidese R, Toyoda M, Yoshino KI, Fukuda W, Wihardja GA, Kimura S, Fujita J, Niitsu M, Oshima T, Imanaka T, Mizohata E, Fujiwara S. The C-terminal flexible region of branched-chain polyamine synthase facilitates substrate specificity and catalysis. FEBS J 2019; 286:3926-3940. [PMID: 31162806 DOI: 10.1111/febs.14949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 05/03/2019] [Accepted: 06/01/2019] [Indexed: 01/26/2023]
Abstract
Branched-chain polyamine synthase (BpsA) catalyzes sequential aminopropyl transfer from the donor, decarboxylated S-adenosylmethionine (dcSAM), to the acceptor, linear-chain polyamine, resulting in the production of a quaternary-branched polyamine via tertiary branched polyamine intermediates. Here, we analyzed the catalytic properties and X-ray crystal structure of Tth-BpsA from Thermus thermophilus and compared them with those of Tk-BpsA from Thermococcus kodakarensis, which revealed differences in acceptor substrate specificity and C-terminal structure between these two enzymes. To investigate the role of the C-terminal flexible region in acceptor recognition, a region (QDEEATTY) in Tth-BpsA was replaced with that in Tk-BpsA (YDDEESSTT) to create chimeric Tth-BpsA C9, which showed a severe reduction in catalytic efficiency toward N4 -aminopropylnorspermidine, but not toward N4 -aminopropylspermidine, mimicking Tk-BpsA substrate specificity. Tth-BpsA C9 Tyr346 and Thr354 contributed to discrimination between tertiary branched-chain polyamine substrates, suggesting that the C-terminal region of BpsA recognizes acceptor substrates. Liquid chromatography-tandem mass spectrometry analysis on a Tk-BpsA reaction mixture with dcSAM revealed two aminopropyl groups bound to two of five aspartate/glutamate residues (Glu339 , Asp342 , Asp343 , Glu344 , and Glu345 ) in the C-terminal flexible region. Mutating each of these five amino acid residues to asparagine/glutamine resulted in a slight decrease in activity. The quadruple mutant D342N/D343N/E344Q/E345Q exhibited a severe reduction in catalytic efficiency, suggesting that these aspartate/glutamate residues function to receive aminopropyl chains. In addition, the X-ray crystal structure of the Tk-BpsA ternary complex bound to N4 -bis(aminopropyl)spermidine revealed that Asp126 and Glu259 interacted with the aminopropyl moiety in N4 -aminopropylspermidine.
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Affiliation(s)
- Ryota Hidese
- Department of Bioscience, Graduate School of Science and Technology, Kwansei-Gakuin University, Sanda, Japan
| | - Masataka Toyoda
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Japan
| | | | - Wakao Fukuda
- Department of Bioscience, Graduate School of Science and Technology, Kwansei-Gakuin University, Sanda, Japan
| | - Gita Adhirani Wihardja
- Department of Bioscience, Graduate School of Science and Technology, Kwansei-Gakuin University, Sanda, Japan
| | - Seigo Kimura
- Department of Bioscience, Graduate School of Science and Technology, Kwansei-Gakuin University, Sanda, Japan
| | - Junso Fujita
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Japan
| | - Masaru Niitsu
- Faculty of Pharmacy and Pharmaceutical Sciences, Josai University, Sakado, Japan
| | - Tairo Oshima
- Institute of Environmental Microbiology, Kyowa-kako Co., Ltd, Machida, Japan
| | - Tadayuki Imanaka
- The Research Organization of Science & Technology, Ritsumeikan University, Kusatsu, Japan
| | - Eiichi Mizohata
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Japan.,Japan Science and Technology Agency, PRESTO, Kawaguchi, Japan
| | - Shinsuke Fujiwara
- Department of Bioscience, Graduate School of Science and Technology, Kwansei-Gakuin University, Sanda, Japan
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Spinocerebellar ataxia type 14 caused by a nonsense mutation in the PRKCG gene. Mol Cell Neurosci 2019; 98:46-53. [PMID: 31158466 DOI: 10.1016/j.mcn.2019.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/25/2019] [Accepted: 05/30/2019] [Indexed: 12/15/2022] Open
Abstract
Spinocerebellar ataxia type 14 (SCA14) is an autosomal dominant neurodegenerative disorder characterized by cerebellar ataxia with myoclonus, dystonia, spasticity, and rigidity. Although missense mutations and a deletion mutation have been found in the protein kinase C gamma (PRKCG) gene encoding protein kinase C γ (PKCγ) in SCA14 families, a nonsense mutation has not been reported. The patho-mechanisms underlying SCA14 remain poorly understood. However, gain-of-function mechanisms and loss-of-function mechanisms, but not dominant negative mechanisms, were reported the patho-mechanism of SCA14. We identified the c.226C>T mutation of PRKCG, which caused the p.R76X in PKCγ by whole-exome sequencing in patients presenting cerebellar atrophy with cognitive and hearing impairment. To investigate the patho-mechanism of our case, we studied aggregation formation, cell death, and PKC inhibitory effect by confocal microscopy, western blotting with cleaved caspase 3, and pSer PKC motif antibodies, respectively. PKCγ(R76X)-GFP have aggregations the same as wild-type (WT) PKCγ-GFP. The PKCγ(R76X)-GFP inhibited PKC phosphorylation activity more than GFP alone. It also induced more apoptosis in COS7 and SH-SY5Y cells compared to WT-PKCγ-GFP and GFP. We first reported SCA14 patients with p.R76X in PKCγ who have cerebellar atrophy with cognitive and hearing impairment. Our results suggest that a dominant negative mechanism due to truncated peptides produced by p.R76X may be at least partially responsible for the cerebellar atrophy.
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