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Akinyele O, Munir A, Johnson MA, Perez MS, Gao Y, Foley JR, Nwafor A, Wu Y, Murray-Stewart T, Casero RA, Bayir H, Kemaladewi DU. Impaired polyamine metabolism causes behavioral and neuroanatomical defects in a mouse model of Snyder-Robinson syndrome. Dis Model Mech 2024; 17:dmm050639. [PMID: 38463005 PMCID: PMC11103582 DOI: 10.1242/dmm.050639] [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: 11/30/2023] [Accepted: 02/28/2024] [Indexed: 03/12/2024] Open
Abstract
Snyder-Robinson syndrome (SRS) is a rare X-linked recessive disorder caused by a mutation in the SMS gene, which encodes spermine synthase, and aberrant polyamine metabolism. SRS is characterized by intellectual disability, thin habitus, seizure, low muscle tone/hypotonia and osteoporosis. Progress towards understanding and treating SRS requires a model that recapitulates human gene variants and disease presentations. Here, we evaluated molecular and neurological presentations in the G56S mouse model, which carries a missense mutation in the Sms gene. The lack of SMS protein in the G56S mice resulted in increased spermidine/spermine ratio, failure to thrive, short stature and reduced bone density. They showed impaired learning capacity, increased anxiety, reduced mobility and heightened fear responses, accompanied by reduced total and regional brain volumes. Furthermore, impaired mitochondrial oxidative phosphorylation was evident in G56S cerebral cortex, G56S fibroblasts and Sms-null hippocampal cells, indicating that SMS may serve as a future therapeutic target. Collectively, our study establishes the suitability of the G56S mice as a preclinical model for SRS and provides a set of molecular and functional outcome measures that can be used to evaluate therapeutic interventions for SRS.
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Affiliation(s)
- Oluwaseun Akinyele
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Anushe Munir
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Marie A. Johnson
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Megan S. Perez
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Yuan Gao
- Children's Neuroscience Institute, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Jackson R. Foley
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
| | - Ashley Nwafor
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
| | - Yijen Wu
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Tracy Murray-Stewart
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
| | - Robert A. Casero
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
| | - Hülya Bayir
- Children's Neuroscience Institute, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
| | - Dwi U. Kemaladewi
- Division of Genetic and Genomic Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Children's Neuroscience Institute, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, USA
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Matsui Y, Djekidel MN, Lindsay K, Samir P, Connolly N, Wu G, Yang X, Fan Y, Xu B, Peng JC. SNIP1 and PRC2 coordinate cell fates of neural progenitors during brain development. Nat Commun 2023; 14:4754. [PMID: 37553330 PMCID: PMC10409800 DOI: 10.1038/s41467-023-40487-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
Stem cell survival versus death is a developmentally programmed process essential for morphogenesis, sizing, and quality control of genome integrity and cell fates. Cell death is pervasive during development, but its programming is little known. Here, we report that Smad nuclear interacting protein 1 (SNIP1) promotes neural progenitor cell survival and neurogenesis and is, therefore, integral to brain development. The SNIP1-depleted brain exhibits dysplasia with robust induction of caspase 9-dependent apoptosis. Mechanistically, SNIP1 regulates target genes that promote cell survival and neurogenesis, and its activities are influenced by TGFβ and NFκB signaling pathways. Further, SNIP1 facilitates the genomic occupancy of Polycomb complex PRC2 and instructs H3K27me3 turnover at target genes. Depletion of PRC2 is sufficient to reduce apoptosis and brain dysplasia and to partially restore genetic programs in the SNIP1-depleted brain in vivo. These findings suggest a loci-specific regulation of PRC2 and H3K27 marks to toggle cell survival and death in the developing brain.
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Affiliation(s)
- Yurika Matsui
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Mohamed Nadhir Djekidel
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Katherine Lindsay
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Parimal Samir
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
- Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd, Medical Research Building, Room 7, 138E, Galveston, TX, 77550, USA
| | - Nina Connolly
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Gang Wu
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Xiaoyang Yang
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Yiping Fan
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Beisi Xu
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA
| | - Jamy C Peng
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN, 38105, USA.
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Akinyele O, Munir A, Johnson MA, Perez MS, Gao Y, Foley JR, Wu Y, Murray-Stewart T, Casero RA, Bayir H, Kemaladewi DU. Impaired polyamine metabolism causes behavioral and neuroanatomical defects in a novel mouse model of Snyder-Robinson Syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.15.524155. [PMID: 36711956 PMCID: PMC9882240 DOI: 10.1101/2023.01.15.524155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Polyamines (putrescine, spermidine, and spermine) are essential molecules for normal cellular functions and are subject to strict metabolic regulation. Mutations in the gene encoding spermine synthase (SMS) lead to accumulation of spermidine in an X-linked recessive disorder known as Snyder-Robinson syndrome (SRS). Presently, no treatments exist for this rare disease that manifests with a spectrum of symptoms including intellectual disability, developmental delay, thin habitus, and low muscle tone. The development of therapeutic interventions for SRS will require a suitable disease-specific animal model that recapitulates many of the abnormalities observed in patients. Here, we characterize the molecular, behavioral, and neuroanatomical features of a mouse model with a missense mutation in Sms gene that results in a glycine-to-serine substitution at position 56 (G56S) of the SMS protein. Mice harboring this mutation exhibit a complete loss of SMS protein and elevated spermidine/spermine ratio in skeletal muscles and the brain. In addition, the G56S mice demonstrate increased anxiety, impaired learning, and decreased explorative behavior in fear conditioning, Morris water maze, and open field tests, respectively. Furthermore, these mice failed to gain weight over time and exhibit abnormalities in brain structure and bone density. Transcriptomic analysis of the cerebral cortex revealed downregulation of genes associated with mitochondrial oxidative phosphorylation and ribosomal protein synthesis. Our findings also revealed impaired mitochondrial bioenergetics in fibroblasts isolated from the G56S mice, indicating a correlation between these processes in the affected mice. Collectively, our findings establish the first in-depth characterization of an SRS preclinical mouse model that identifies cellular processes that could be targeted for future therapeutic development.
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Affiliation(s)
- Oluwaseun Akinyele
- Div. of Genetic and Genomic Medicine, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Anushe Munir
- Div. of Genetic and Genomic Medicine, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Dept. of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, USA
| | - Marie A. Johnson
- Div. of Genetic and Genomic Medicine, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Megan S. Perez
- Div. of Genetic and Genomic Medicine, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Dept. of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, USA
| | - Yuan Gao
- Children’s Neuroscience Institute, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Jackson R. Foley
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Yijen Wu
- Dept. of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Tracy Murray-Stewart
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Robert A. Casero
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Hulya Bayir
- Children’s Neuroscience Institute, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Dwi U. Kemaladewi
- Div. of Genetic and Genomic Medicine, Dept. of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Dept. of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, USA
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Henneghan AM, Lewis KA, Gill E, Kesler SR. Cognitive Impairment in Non-critical, Mild-to-Moderate COVID-19 Survivors. Front Psychol 2022; 13:770459. [PMID: 35250714 PMCID: PMC8891805 DOI: 10.3389/fpsyg.2022.770459] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/21/2022] [Indexed: 12/15/2022] Open
Abstract
IMPORTANCE Previous studies of post-acute COVID-19 syndrome have focused on critical cases with severe disease. However, most cases are mild to moderate in disease severity. OBJECTIVE We aimed to examine cognitive outcomes in cases of non-critical, mild-to-moderate COVID-19. Design, Setting, and Participants: In this cross-sectional study, we enrolled 72 adults aged 22 to 65 years in Central Texas who had non-critical, mild-to-moderate COVID-19 infection between 13 January 2021 and 20 April 2021. MAIN OUTCOMES AND MEASURES We remotely administered cognitive-behavioral testing to determine the frequency of cognitive impairment and examine demographic, clinical, and psychosocial contributors to impairment. RESULTS The frequency of objective cognitive impairment was 40%. The largest number of participants (24%) showed impairment on a measure of executive functioning. Attention and processing speed was more impaired in males (OR = 1.5, 95%CI = 0.23-2.9). Males endorsed lower adherence to social distancing guidelines (U = 590, p = 0.01), which was in turn associated with cognitive impairment across participants (r = -0.30, p = 0.01). Younger age was correlated with impairment (r = -0.26, p = 0.03) but was also associated with racial/ethnic minority status (r = -0.31, p = 0.01) and increased psychological symptoms (p < 0.04). Greater number of COVID-19 symptoms was correlated with lower subjective cognitive function (r = -0.38, p = 0.001) as well as psychosocial function (r > 0.24, p < 0.05). Moderate COVID-19 severity was associated with attention/processing speed impairment (r = 0.27, p = 0.03), increased pain (r = 0.31, p = 0.01), and higher number of COVID-19 symptoms (r = 0.32, p = 0.01). CONCLUSION AND RELEVANCE Mild or moderate COVID-19 infection may be associated with cognitive impairments, especially in the domain of executive functioning. A subgroup of younger individuals may be more vulnerable to cognitive and psychosocial effects of COVID-19. HIGHLIGHTS Question: How frequent is cognitive impairment among non-critical, mild-to-moderate COVID-19 survivors? FINDINGS In this cross-sectional study of 72 adults, 40% demonstrated cognitive impairment, particularly in executive function. MEANING Neurologic sequelae, such as cognitive impairment, may be common following COVID-19 infection.
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Affiliation(s)
- Ashley M. Henneghan
- School of Nursing, The University of Texas at Austin, Austin, TX, United States
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX, United States
| | - Kimberly A. Lewis
- Ascension Seton Medical Center, Austin, TX, United States
- Department of Physiological Nursing, University of California, San Francisco, San Francisco, CA, United States
| | - Eliana Gill
- School of Nursing, The University of Texas at Austin, Austin, TX, United States
- Ascension Seton Medical Center, Austin, TX, United States
| | - Shelli R. Kesler
- School of Nursing, The University of Texas at Austin, Austin, TX, United States
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX, United States
- Department of Diagnostic Medicine, Dell Medical School, The University of Texas at Austin, Austin, TX, United States
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Dontaine P, Kottos E, Dassonville M, Balasel O, Catros V, Soblet J, Perlot P, Vilain C. Digestive involvement in a severe form of Snyder-Robinson syndrome: Possible expansion of the phenotype. Eur J Med Genet 2020; 64:104097. [PMID: 33186760 DOI: 10.1016/j.ejmg.2020.104097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 10/23/2020] [Accepted: 11/04/2020] [Indexed: 11/30/2022]
Abstract
Snyder-Robinson syndrome (OMIM #309583) is a rare X-linked condition, caused by mutation in the SMS gene (MIM *300105), characterized by a wide spectrum of clinical signs including developmental delay, epilepsy, asthenic habitus, dysmorphism, osteopenia, and renal or genital anomalies. Here we describe two maternal half-brothers who both presented with severe neurodevelopmental delay, seizures, hearing loss, facial dysmorphism, renal and ophthalmologic anomalies, failure to thrive and premature death. A novel p.(Gly203Asp) variant was found at the hemizygous state in the two boys, and an elevated Spermidine/Spermine ratio confirmed the diagnosis of Snyder-Robinson syndrome. One of the brothers presented with gastrointestinal symptoms, with jejunal stenosis, enteral feeding intolerance, failure to thrive due to a dysfunctional gastrointestinal system, cholestasis and exocrine pancreatic insufficiency. Although more studies will be needed to understand its mechanisms, this observation lends further support to the possibility of severe digestive involvement in Snyder Robinson syndrome.
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Affiliation(s)
- Pauline Dontaine
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium
| | - Elisa Kottos
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium
| | - Martine Dassonville
- Department of Pediatric Surgery, Hôpital Universitaire des Enfants Reine Fabiola, Universite Libre de Bruxelles, Brussels, Belgium
| | - Ovidiu Balasel
- Department of Neonatalogy, Hôpital Universitaire des Enfants Reine Fabiola, Universite Libre de Bruxelles, Brussels, Belgium
| | - Véronique Catros
- Univ Rennes, Inserm, CHU Rennes, Institut NUMECAN (Nutrition Metabolisms and Cancer), CRB Santé Rennes, F-35000, Rennes, France
| | - Julie Soblet
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium; Department of Genetics, Hôpital Erasme, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium; Interuniversity Institute of Bioinformatics in Brussels, Universite Libre de Bruxelles, Brussels, Belgium
| | - Pascale Perlot
- Department of Pediatrics, Hôpital Universitaire des Enfants Reine Fabiola, Universite Libre de Bruxelles, Brussels, Belgium
| | - Catheline Vilain
- Department of Genetics, Hôpital Universitaire des Enfants Reine Fabiola, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium; Department of Genetics, Hôpital Erasme, ULB Center of Human Genetics, Universite Libre de Bruxelles, Brussels, Belgium; Interuniversity Institute of Bioinformatics in Brussels, Universite Libre de Bruxelles, Brussels, Belgium.
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6
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Myosin Va and spermine synthase: partners in exosome transport. Biosci Rep 2019; 39:BSR20190326. [PMID: 30967493 PMCID: PMC6488853 DOI: 10.1042/bsr20190326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 11/21/2022] Open
Abstract
A recent paper in Bioscience Reports (BSR20182189) describes the discovery of an
interaction between the motor protein myosin Va and the metabolic enzyme
spermine synthase. Myosin Va is a molecular motor which plays a key role in
vesicle transport. Mutations in the gene which encodes this protein are
associated with Griscelli syndrome type 1 and the ‘dilute’
phenotype in animals. Spermine synthase catalyzes the conversion of spermidine
to spermine. This largely cytoplasmic enzyme can also be localized to the
soluble fraction in exosomes. Mutations in the spermine synthase gene are
associated with Snyder Robinson mental retardation syndrome. The interaction
between the two proteins was detected using the yeast two hybrid method and
verified by microscale thermophoresis of recombinant proteins. Knockdown of the
MYO5A gene reduced the expression of mRNA coding for
spermine synthase. The amount of this transcript was also reduced in cells
derived from a patient with Griscelli syndrome type 1. This suggests that, in
addition to a direct physical interaction between the two proteins, myosin Va
also modulates the transcription of the spermine synthase gene. The mechanism
for this modulation is currently unknown. These findings have implications for
Griscelli syndrome type 1 and Snyder Robinson mental retardation syndrome. They
also suggest that interactions between myosin Va and soluble exosome proteins
such as spermine synthase may be important in the mechanism of exosome
transport.
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7
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Myosin Va interacts with the exosomal protein spermine synthase. Biosci Rep 2019; 39:BSR20182189. [PMID: 30733278 PMCID: PMC6395372 DOI: 10.1042/bsr20182189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/31/2019] [Accepted: 02/05/2019] [Indexed: 12/17/2022] Open
Abstract
Myosin Va (MyoVa) is an actin-based molecular motor that plays key roles in the final stages of secretory pathways, including neurotransmitter release. Several studies have addressed how MyoVa coordinates the trafficking of secretory vesicles, but why this molecular motor is found in exosomes is still unclear. In this work, using a yeast two-hybrid screening system, we identified the direct interaction between the globular tail domain (GTD) of MyoVa and four protein components of exosomes: the WD repeat-containing protein 48 (WDR48), the cold shock domain-containing protein E1 (CSDE1), the tandem C2 domain-containing protein 1 (TC2N), and the enzyme spermine synthase (SMS). The interaction between the GTD of MyoVa and SMS was further validated in vitro and displayed a Kd in the low micromolar range (3.5 ± 0.5 µM). SMS localized together with MyoVa in cytoplasmic vesicles of breast cancer MCF-7 and neuroblastoma SH-SY5Y cell lines, known to produce exosomes. Moreover, MYO5A knockdown decreased the expression of SMS gene and rendered the distribution of SMS protein diffuse, supporting a role for MyoVa in SMS expression and targeting.
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Starks R, Kirby P, Ciliberto M, Hefti M. Snyder-Robinson syndrome. AUTOPSY AND CASE REPORTS 2018; 8:e2018031. [PMID: 30237987 PMCID: PMC6140707 DOI: 10.4322/acr.2018.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 06/17/2018] [Indexed: 11/23/2022] Open
Abstract
Snyder-Robinson syndrome, also known as spermine synthase deficiency, is an X-linked intellectual disability syndrome (OMIM #390583). First described by Drs. Snyder and Robinson in 1969, this syndrome is characterized by an asthenic body habitus, facial dysmorphism, broad-based gait, and osteoporosis with frequent fractures. We report here a pediatric autopsy of a 4 year old male with a history of intellectual disability, gait abnormalities, multiple fractures, and seizures previously diagnosed with Snyder-Robinson syndrome with an SMS gene mutation (c.831G>T:p.L277F). The cause of death was hypoxic-ischemic encephalopathy secondary to prolonged seizure activity. Although Snyder-Robinson syndrome is rare, the need to recognize clinical findings in order to trigger genetic testing has likely resulted in under diagnosis.
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Affiliation(s)
- Rachel Starks
- University of Iowa Hospitals and Clinics, Department of Pathology. Iowa City, IA, United States of America
| | - Patricia Kirby
- University of Iowa Hospitals and Clinics, Department of Pathology. Iowa City, IA, United States of America
| | - Michael Ciliberto
- University of Iowa Hospitals and Clinics, Department of Pediatrics. Iowa City, IA, United States of America
| | - Marco Hefti
- University of Iowa Hospitals and Clinics, Department of Pathology. Iowa City, IA, United States of America
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9
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Kang B, Xu Q, Chen Z, Wu Y, Yang S, Yang X, Zhang Z, Jiang D. Characterization of goose SPMS: Molecular characterization and expression profiling of SPMS in the goose ovary. Reprod Biol 2018; 18:60-65. [PMID: 29336947 DOI: 10.1016/j.repbio.2018.01.003] [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: 09/30/2017] [Revised: 12/13/2017] [Accepted: 01/04/2018] [Indexed: 11/24/2022]
Abstract
Spermine synthase (SPMS), which converts spermidine into spermine, is essential for normal cell growth and development processes in humans and other mammals, but the molecular characterization and expression profiling of the SPMS gene remain undetermined in goose tissues and ovarian follicles. In this study, the SPMS cDNA sequence of the Sichuan white goose was cloned and analysed, and SPMS mRNA expression was profiled in various tissues and ovarian follicles. The results showed that the open reading frame of the SPMS cDNA sequence was 1092 bp in length, encoding 363 amino acids with a molecular weight of 41 kDa. Among all the examined tissues, SPMS expression was highest in the spleen and cerebrum and lowest in the breast and thigh muscles. SPMS expression in the F1 follicle was significantly higher than that in the POF (except for POF2) (P < 0.05). Our results indicate that SPMS might play an important role in follicular development and ovulation.
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Affiliation(s)
- Bo Kang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China
| | - Qilin Xu
- Institute of Animal Science, Chengdu Academy of Agriculture and Forestry Sciences, Chengdu, PR China
| | - Ziyu Chen
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China
| | - Yongsheng Wu
- Institute of Animal Science, Chengdu Academy of Agriculture and Forestry Sciences, Chengdu, PR China
| | - Su Yang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China
| | - Xicheng Yang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China
| | - Zhao Zhang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China
| | - Dongmei Jiang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, PR China.
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10
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Abstract
The content of spermidine and spermine in mammalian cells has important roles in protein and nucleic acid synthesis and structure, protection from oxidative damage, activity of ion channels, cell proliferation, differentiation, and apoptosis. Spermidine is essential for viability and acts as the precursor of hypusine, a post-translational addition to eIF5A allowing the translation of mRNAs encoding proteins containing polyproline tracts. Studies with Gy mice and human patients with the very rare X-linked genetic condition Snyder-Robinson syndrome that both lack spermine synthase show clearly that the correct spermine:spermidine ratio is critical for normal growth and development.
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Affiliation(s)
- Anthony E Pegg
- From the Department of Cellular and Molecular Physiology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
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11
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Abela L, Simmons L, Steindl K, Schmitt B, Mastrangelo M, Joset P, Papuc M, Sticht H, Baumer A, Crowther LM, Mathis D, Rauch A, Plecko B. N(8)-acetylspermidine as a potential plasma biomarker for Snyder-Robinson syndrome identified by clinical metabolomics. J Inherit Metab Dis 2016; 39:131-7. [PMID: 26174906 DOI: 10.1007/s10545-015-9876-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 06/16/2015] [Accepted: 06/16/2015] [Indexed: 11/26/2022]
Abstract
Clinical metabolomics has emerged as a powerful tool to study human metabolism in health and disease. Comparative statistical analysis of untargeted metabolic profiles can reveal perturbations of metabolite levels in diseases and thus has the potential to identify novel biomarkers. Here we have applied a simultaneous genetic-metabolomic approach in twin boys with epileptic encephalopathy of unclear etiology. Clinical exome sequencing identified a novel missense mutation in the spermine synthase gene (SMS) that causes Snyder-Robinson syndrome (SRS). Untargeted plasma metabolome analysis revealed significantly elevated levels of N(8)-acetylspermidine, a precursor derivative of spermine biosynthesis, as a potential novel plasma biomarker for SRS. This result was verified in a third patient with genetically confirmed SRS. This study illustrates the potential of metabolomics as a translational technique to support exome data on a functional and clinical level.
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Affiliation(s)
- Lucia Abela
- Division of Child Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Children's Research Centre, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Luke Simmons
- Division of Child Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Children's Research Centre, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Katharina Steindl
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Institute of Medical Genetics, University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Bernhard Schmitt
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Division of Epilepsy and Neurophysiology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Massimo Mastrangelo
- Pediatric Neurology Unit, V. Buzzi Children's Hospital, ICP, Via Castelvetro 24, 20154, Milan, Italy
| | - Pascal Joset
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Institute of Medical Genetics, University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Mihaela Papuc
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Institute of Medical Genetics, University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Heinrich Sticht
- Institute for Biochemistry, University of Erlangen-Nuernberg, Fahrstrasse 17, 91054, Erlangen, Germany
| | - Alessandra Baumer
- Institute of Medical Genetics, University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Lisa M Crowther
- Division of Child Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Children's Research Centre, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Déborah Mathis
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Anita Rauch
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland
- Institute of Medical Genetics, University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Barbara Plecko
- Division of Child Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland.
- Children's Research Centre, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland.
- Radiz-Rare Disease Initiative Zurich, Clinical Research Priority Program for Rare Diseases, University of Zurich, Steinwiesstrasse 75, 8032, Zurich, Switzerland.
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Abstract
Background The importance of mutations in disease phenotype has been studied, with information available in databases such as OMIM. However, it remains a research challenge for the possibility of clustering amino acid residues based on an underlying interaction, such as co-evolution, to understand how mutations in these related sites can lead to different disease phenotypes. Results This paper presents an integrative approach to identify groups of co-evolving residues, known as protein sectors. By studying a protein family using multiple sequence alignments and statistical coupling analysis, we attempted to determine if it is possible that these groups of residues could be related to disease phenotypes. After the protein sectors were identified, disease-associated residues within these groups of amino acids were mapped to a structure representing the protein family. In this study, we used the proposed pipeline to analyze two test cases of spermine synthase and Rab GDP dissociation inhibitor. Conclusions The results suggest that there is a possible link between certain groups of co-evolving residues and different disease phenotypes. The pipeline described in this work could also be used to study other protein families associated with human diseases.
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Peron A, Spaccini L, Norris J, Bova SM, Selicorni A, Weber G, Wood T, Schwartz CE, Mastrangelo M. Snyder-Robinson syndrome: A novel nonsense mutation in spermine synthase and expansion of the phenotype. Am J Med Genet A 2013; 161A:2316-20. [DOI: 10.1002/ajmg.a.36116] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 05/27/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Angela Peron
- Clinical Genetics Service; V. Buzzi Children's Hospital; ICP Milan Italy
| | - Luigina Spaccini
- Clinical Genetics Service; V. Buzzi Children's Hospital; ICP Milan Italy
| | - Joy Norris
- JC Self Research Institute; Greenwood Genetic Center; Greenwood South Carolina
| | - Stefania M. Bova
- Pediatric Neurology Unit; V. Buzzi Children's Hospital; ICP Milan Italy
| | | | - Giovanna Weber
- Pediatrics Clinic; Vita-Salute San Raffaele University; Milan Italy
| | - Tim Wood
- JC Self Research Institute; Greenwood Genetic Center; Greenwood South Carolina
| | - Charles E. Schwartz
- JC Self Research Institute; Greenwood Genetic Center; Greenwood South Carolina
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14
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Kesler S, Janelsins M, Koovakkattu D, Palesh O, Mustian K, Morrow G, Dhabhar FS. Reduced hippocampal volume and verbal memory performance associated with interleukin-6 and tumor necrosis factor-alpha levels in chemotherapy-treated breast cancer survivors. Brain Behav Immun 2013; 30 Suppl:S109-16. [PMID: 22698992 PMCID: PMC3665606 DOI: 10.1016/j.bbi.2012.05.017] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 05/29/2012] [Accepted: 05/31/2012] [Indexed: 11/16/2022] Open
Abstract
Many survivors of breast cancer show significant cognitive impairments, including memory deficits. Inflammation induced by chemotherapy may contribute to hippocampal changes that underlie these deficits. In this cross-sectional study, we measured bilateral hippocampal volumes from high-resolution magnetic resonance images in 42 chemotherapy-treated breast cancer survivors and 35 healthy female controls. Patients with breast cancer were, on average, 4.8 ± 3.4 years off-therapy. In a subset of these participants (20 breast cancer, 23 controls), we quantified serum cytokine levels. Left hippocampal volumes and memory performance were significantly reduced and interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNFα) concentrations were significantly elevated in the breast cancer group compared to controls. In the breast cancer group, lower left hippocampal volume was associated with higher levels of TNFα and lower levels of IL-6 with a significant interaction between these two cytokines suggesting a potential modulatory effect of IL-6 on TNFα. Verbal memory performance was associated with cytokine levels and left hippocampal volume in both groups. These findings provide evidence of altered hippocampal volume and verbal memory difficulties following breast cancer chemotherapy that may be mediated by TNFα and IL-6.
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Affiliation(s)
- Shelli Kesler
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Michelle Janelsins
- Department of Radiation Oncology, University of Rochester, Rochester, NY 14642, United States
| | - Della Koovakkattu
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, United States
| | - Oxana Palesh
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, United States
| | - Karen Mustian
- Department of Radiation Oncology, University of Rochester, Rochester, NY 14642, United States
| | - Gary Morrow
- Department of Radiation Oncology, University of Rochester, Rochester, NY 14642, United States
| | - Firdaus S. Dhabhar
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, United States
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15
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Hamon L, Savarin P, Curmi PA, Pastré D. Rapid assembly and collective behavior of microtubule bundles in the presence of polyamines. Biophys J 2011; 101:205-16. [PMID: 21723831 DOI: 10.1016/j.bpj.2011.05.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 04/21/2011] [Accepted: 05/10/2011] [Indexed: 12/31/2022] Open
Abstract
Microtubules (MTs) are cylindrical cytoskeleton polymers composed of α-β tubulin heterodimers whose dynamic properties are essential to fulfill their numerous cellular functions. In response to spatial confinement, dynamic MTs, even in the absence of protein partners, were shown to self-organize into higher order structures (spindle or striped structures) which lead to interesting dynamical properties (MT oscillations). In this study, we considered the assembly and sensitivity of dynamic MTs when in bundles. To perform this study, spermine, a natural tetravalent polyamine present at high concentrations in all eukaryote cells, was used to trigger MT bundling while preserving MT dynamics. Interestingly, we first show that, near physiological ionic strengths, spermine promotes the bundling of MTs whereas it does not lead to aggregation of free tubulin, which would have been detrimental to MT polymerization. Experimental and theoretical results also indicate that, to obtain a high rate of bundle assembly, bundling should take place at the beginning of assembly when rapid rotational movements of short and newly nucleated MTs are still possible. On the other hand, the bundling process is significantly slowed down for long MTs. Finally, we found that short MT bundles exhibit a higher sensitivity to cold exposure than do isolated MTs. To account for this phenomenon, we suggest that a collective behavior takes place within MT bundles because an MT entering into a phase of shortening could increase the probability of the other MTs in the same bundle to enter into shortening phase due to their close proximity. We then elaborate on some putative applications of our findings to in vivo conditions including neurons.
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Affiliation(s)
- Loïc Hamon
- Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Institut National de la Santé et de la Recherche Médicale, U829, and Université Evry-Val d'Essonne, EA3637, Evry, France.
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16
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Zhang Z, Norris J, Schwartz C, Alexov E. In silico and in vitro investigations of the mutability of disease-causing missense mutation sites in spermine synthase. PLoS One 2011; 6:e20373. [PMID: 21647366 PMCID: PMC3103547 DOI: 10.1371/journal.pone.0020373] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 04/30/2011] [Indexed: 01/17/2023] Open
Abstract
Background Spermine synthase (SMS) is a key enzyme controlling the concentration of spermidine and spermine in the cell. The importance of SMS is manifested by the fact that single missense mutations were found to cause Snyder-Robinson Syndrome (SRS). At the same time, currently there are no non-synonymous single nucleoside polymorphisms, nsSNPs (harmless mutations), found in SMS, which may imply that the SMS does not tolerate amino acid substitutions, i.e. is not mutable. Methodology/Principal Findings To investigate the mutability of the SMS, we carried out in silico analysis and in vitro experiments of the effects of amino acid substitutions at the missense mutation sites (G56, V132 and I150) that have been shown to cause SRS. Our investigation showed that the mutation sites have different degree of mutability depending on their structural micro-environment and involvement in the function and structural integrity of the SMS. It was found that the I150 site does not tolerate any mutation, while V132, despite its key position at the interface of SMS dimer, is quite mutable. The G56 site is in the middle of the spectra, but still quite sensitive to charge residue replacement. Conclusions/Significance The performed analysis showed that mutability depends on the detail of the structural and functional factors and cannot be predicted based on conservation of wild type properties alone. Also, harmless nsSNPs can be expected to occur even at sites at which missense mutations were found to cause diseases.
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Affiliation(s)
- Zhe Zhang
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, South Carolina, United States of America
| | - Joy Norris
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina, United States of America
| | - Charles Schwartz
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina, United States of America
- Department of Genetics and Biochemistry, Clemson University, Clemson, South Carolina, United States of America
| | - Emil Alexov
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, South Carolina, United States of America
- * E-mail:
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Fiori LM, Wanner B, Jomphe V, Croteau J, Vitaro F, Tremblay RE, Bureau A, Turecki G. Association of polyaminergic loci with anxiety, mood disorders, and attempted suicide. PLoS One 2010; 5:e15146. [PMID: 21152090 PMCID: PMC2994870 DOI: 10.1371/journal.pone.0015146] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 10/26/2010] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The polyamine system has been implicated in a number of psychiatric conditions, which display both alterations in polyamine levels and altered expression of genes related to polyamine metabolism. Studies have identified associations between genetic variants in spermidine/spermine N1-acetyltransferase (SAT1) and both anxiety and suicide, and several polymorphisms appear to play important roles in determining gene expression. METHODOLOGY/PRINCIPAL FINDINGS We genotyped 63 polymorphisms, spread across four polyaminergic genes (SAT1, spermine synthase (SMS), spermine oxidase (SMOX), and ornithine aminotransferase like-1 (OATL1)), in 1255 French-Canadian individuals who have been followed longitudinally for 22 years. We assessed univariate associations with anxiety, mood disorders, and attempted suicide, as assessed during early adulthood. We also investigated the involvement of gene-environment interactions in terms of childhood abuse, and assessed internalizing and externalizing symptoms as endophenotypes mediating these interactions. Overall, each gene was associated with at least one main outcome: anxiety (SAT1, SMS), mood disorders (SAT1, SMOX), and suicide attempts (SAT1, OATL1). Several SAT1 polymorphisms displayed disease-specific risk alleles, and polymorphisms in this gene were involved in gene-gene interactions with SMS to confer risk for anxiety disorders, as well as gene-environment interactions between childhood physical abuse and mood disorders. Externalizing behaviors demonstrated significant mediation with regards to the association between OATL1 and attempted suicide, however there was no evidence that externalizing or internalizing behaviors were appropriate endophenotypes to explain the associations with mood or anxiety disorders. Finally, childhood sexual abuse did not demonstrate mediating influences on any of our outcomes. CONCLUSIONS/SIGNIFICANCE These results demonstrate that genetic variants in polyaminergic genes are associated with psychiatric conditions, each of which involves a set of separate and distinct risk alleles. As several of these polymorphisms are associated with gene expression, these findings may provide mechanisms to explain the alterations in polyamine metabolism which have been observed in psychiatric disorders.
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Affiliation(s)
- Laura M. Fiori
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, Canada
| | - Brigitte Wanner
- Research Unit on Children's Psychosocial Maladjustment, Université de Montréal, Montreal, Quebec, Canada
| | - Valérie Jomphe
- Centre de recherche Université Laval Robert-Giffard, Université Laval, Quebec City, Quebec, Canada
| | - Jordie Croteau
- Centre de recherche Université Laval Robert-Giffard, Université Laval, Quebec City, Quebec, Canada
| | - Frank Vitaro
- Research Unit on Children's Psychosocial Maladjustment, Université de Montréal, Montreal, Quebec, Canada
| | - Richard E. Tremblay
- Research Unit on Children's Psychosocial Maladjustment, Université de Montréal, Montreal, Quebec, Canada
- School of Public Health and Population Sciences, University College Dublin, Dublin, Ireland
| | - Alexandre Bureau
- Centre de recherche Université Laval Robert-Giffard, Université Laval, Quebec City, Quebec, Canada
| | - Gustavo Turecki
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, Canada
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18
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Fiori LM, Turecki G. Genetic and epigenetic influences on expression of spermine synthase and spermine oxidase in suicide completers. Int J Neuropsychopharmacol 2010; 13:725-36. [PMID: 20059804 DOI: 10.1017/s1461145709991167] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alterations in the levels of spermine synthase (SMS) and spermine oxidase (SMOX), two enzymes involved in polyamine metabolism, have previously been observed in brains of suicide completers. To characterize the roles played by genetic and epigenetic factors in determining expression levels of these genes, as well as to identify potential mechanisms by which to explain our findings in suicide completers, we (1) assessed the role of promoter polymorphisms in determining expression in the brain and in vitro, and (2) examined CpG methylation and levels of methylated histone H3 lysine-27 in the promoter regions of these genes in the prefrontal cortex of suicide completers and healthy controls. We identified several promoter haplotypes in SMS and SMOX, but found no consistent effects of haplotype on expression levels in either the brain or in reporter gene assays performed in three different cell lines. We also found no overall effects of epigenetic factors in determining expression, with the exception of a relationship between CpG methylation at one site in the promoter of SMOX and its expression in Brodmann area 8/9. In conclusion, the genetic and epigenetic factors examined in this study show little influence on the expression levels of SMS and SMOX, and do not appear to be responsible for the dysregulated expression of these genes in suicide completers.
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Affiliation(s)
- Laura M Fiori
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, Canada
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19
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Pegg AE, Michael AJ. Spermine synthase. Cell Mol Life Sci 2010; 67:113-21. [PMID: 19859664 PMCID: PMC2822986 DOI: 10.1007/s00018-009-0165-5] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 08/24/2009] [Accepted: 09/28/2009] [Indexed: 10/20/2022]
Abstract
Spermine is present in many organisms including animals, plants, some fungi, some archaea, and some bacteria. It is synthesized by spermine synthase, a highly specific aminopropyltransferase. This review describes spermine synthase structure, genetics, and function. Structural and biochemical studies reveal that human spermine synthase is an obligate dimer. Each monomer contains a C-terminal domain where the active site is located, a central linking domain that also forms the lid of the catalytic domain, and an N-terminal domain that is structurally very similar to S-adenosylmethionine decarboxylase. Gyro mice, which have an X-chromosomal deletion including the spermine synthase (SMS) gene, lack all spermine and have a greatly reduced size, sterility, deafness, neurological abnormalities, and a tendency to sudden death. Mutations in the human SMS lead to a rise in spermidine and reduction of spermine causing Snyder-Robinson syndrome, an X-linked recessive condition characterized by mental retardation, skeletal defects, hypotonia, and movement disorders.
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Affiliation(s)
- Anthony E Pegg
- Department of Cellular and Molecular Physiology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
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