RESUMEN
BACKGROUND: In a large pedigree with an unusual phenotype of spastic paraplegia or dystonia and autosomal dominant inheritance, linkage analysis previously mapped the disease to chromosome 2q24-2q31. OBJECTIVE: The aim of this study is to identify the genetic cause and molecular basis of an unusual autosomal dominant spastic paraplegia and dystonia. METHODS: Whole exome sequencing following linkage analysis was used to identify the genetic cause in a large family. Cosegregation analysis was also performed. An additional 384 individuals with spastic paraplegia or dystonia were screened for pathogenic sequence variants in the adenosine triphosphate (ATP) synthase membrane subunit C locus 3 gene (ATP5MC3). The identified variant was submitted to the "GeneMatcher" program for recruitment of additional subjects. Mitochondrial functions were analyzed in patient-derived fibroblast cell lines. Transgenic Drosophila carrying mutants were studied for movement behavior and mitochondrial function. RESULTS: Exome analysis revealed a variant (c.318C > G; p.Asn106Lys) (NM_001689.4) in ATP5MC3 in a large family with autosomal dominant spastic paraplegia and dystonia that cosegregated with affected individuals. No variants were identified in an additional 384 individuals with spastic paraplegia or dystonia. GeneMatcher identified an individual with the same genetic change, acquired de novo, who manifested upper-limb dystonia. Patient fibroblast studies showed impaired complex V activity, ATP generation, and oxygen consumption. Drosophila carrying orthologous mutations also exhibited impaired mitochondrial function and displayed reduced mobility. CONCLUSION: A unique form of familial spastic paraplegia and dystonia is associated with a heterozygous ATP5MC3 variant that also reduces mitochondrial complex V activity.
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Distonía , Trastornos Distónicos , Paraplejía Espástica Hereditaria , Distonía/genética , Trastornos Distónicos/genética , Humanos , Mutación/genética , Paraplejía/genética , Linaje , Fenotipo , Paraplejía Espástica Hereditaria/genéticaRESUMEN
Water footprint (WF) quantifies the impact of paddy field evapotranspiration (ET) and non-point source pollution on water resources and is an evaluation index for water sustainability. However, it is difficult to measure accurately using the existing method, which is based on parameter assumption without considering the field water conditions. In this study, a generic and physically based method for blue, green, and grey water accounting in paddy rice cultivation is introduced. We conducted field experiments using the common flood irrigation (CFI) and water-saving irrigation (SWI) modes in Nanjing, East China. By tracing the sources of ET and the migration process of multiple pollutants (TN, TP, NH4+-N, and NO3--N), the characteristics of blue-green water consumption and the actual amount of water required to dilute pollutants at different growth stages of rice under CFI and SWI were analyzed. The WF of paddy rice was 1000 m3/t (49% WFgreen, 17% WFblue, 34% WFgrey) and 910 m3/t (50% WFgreen, 10% WFblue, 40% WFgrey) for CFI and SWI, respectively. The WF for paddy rice production was reduced by approximately 9% under SWI compared to CFI, with declines of 47% for WFblue and 8% for WFgreen. The SWI mode changed the ratio of blue to green water fluxes in field water by reducing irrigation during non-critical periods, and green water was used preferentially to enhance its utility. This conceptual method is the first to describe the formation mechanism of blue, green, and grey WFs in paddy systems. It can be extended to different scales and agro-ecosystems that show the influence of crop cultivation on water resources.
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Oryza , Agua , Agricultura , China , Ecosistema , Inundaciones , Agua/análisis , Recursos HídricosRESUMEN
UBTF (upstream binding transcription factor) exists as two isoforms; UBTF1 regulates rRNA transcription by RNA polymerase 1, whereas UBTF2 regulates mRNA transcription by RNA polymerase 2. Herein, we describe 4 patients with very similar patterns of neuroregression due to recurrent de novo mutations in UBTF (GRCh37/hg19, NC_000017.10: g.42290219C > T, NM_014233.3: c.628G > A) resulting in the same amino acid change in both UBTF1 and UBTF2 (p.Glu210Lys [p.E210K]). Disease onset in our cohort was at 2.5 to 3 years and characterized by slow progression of global motor, cognitive and behavioral dysfunction. Notable early features included hypotonia with a floppy gait, high-pitched dysarthria and hyperactivity. Later features included aphasia, dystonia, and spasticity. Speech and ambulatory ability were lost by the early teens. Magnetic resonance imaging showed progressive generalized cerebral atrophy (supratentorial > infratentorial) with involvement of both gray and white matter. Patient fibroblasts showed normal levels of UBTF transcripts, increased expression of pre-rRNA and 18S rRNA, nucleolar abnormalities, markedly increased numbers of DNA breaks, defective cell-cycle progression, and apoptosis. Expression of mutant human UBTF1 in Drosophila neurons was lethal. Although no loss-of-function variants are reported in the Exome Aggregation Consortium (ExAC) database and Ubtf-/- is early embryonic lethal in mice, Ubtf+/- mice displayed only mild motor and behavioral dysfunction in adulthood. Our data underscore the importance of including UBTF E210K in the differential diagnosis of neuroregression and suggest that mainly gain-of-function mechanisms contribute to the pathogenesis of the UBTF E210K neuroregression syndrome.
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Mutación Missense/genética , Proteínas del Complejo de Iniciación de Transcripción Pol1/genética , Preescolar , Disartria/genética , Femenino , Ataxia de la Marcha/genética , Humanos , Imagen por Resonancia Magnética , Masculino , Hipotonía Muscular/genética , Linaje , ARN Ribosómico 18S/genéticaRESUMEN
The complexity of neurodegeneration restricts the ability to understand and treat the neurological disorders affecting millions of people worldwide. Therefore, there is an unmet need to develop new and more effective therapeutic strategies to combat these devastating conditions and that will only be achieved with a better understanding of the biological mechanism associated with disease conditions. Recent studies highlight the role of DNA damage, particularly, DNA double-strand breaks (DSBs), in the progression of neuronal loss in a broad spectrum of human neurodegenerative diseases. This is not unexpected because neurons are prone to DNA damage due to their non-proliferative nature and high metabolic activity. However, it is not clear if DSBs is a primary driver of neuronal loss in disease conditions or simply occurs concomitant with disease progression. Here, we provide evidence that supports a critical role of DSBs in the pathogenesis of the neurodegenerative diseases. Among different kinds of DNA damages, DSBs are the most harmful and perilous type of DNA damage and can lead to cell death if left unrepaired or repaired with error. In this review, we explore the current state of knowledge regarding the role of DSBs repair mechanisms in preserving neuronal function and survival and describe how DSBs could drive the molecular mechanisms resulting in neuronal death in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. We also discuss the potential implications of DSBs as a novel therapeutic target and prognostic marker in patients with neurodegenerative conditions.
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Roturas del ADN de Doble Cadena , Predisposición Genética a la Enfermedad , Enfermedades Neurodegenerativas/genética , Animales , Biomarcadores , Daño del ADN , Reparación del ADN por Unión de Extremidades , Reparación del ADN , Diagnóstico Diferencial , Estudios de Asociación Genética , Pruebas Genéticas , Recombinación Homóloga , Humanos , Terapia Molecular Dirigida , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/terapiaRESUMEN
BACKGROUND: Intronic (TTTCA)n insertions in the SAMD12, TNRC6A, and RAPGEF2 genes have been identified as causes of familial cortical myoclonic tremor with epilepsy. OBJECTIVE: To identify the cause of familial cortical myoclonic tremor with epilepsy pedigrees without (TTTCA)n insertions in SAMD12, TNRC6A, and RAPGEF2. METHODS: Repeat-primed polymerase chain reaction, long-range polymerase chain reaction, and Sanger sequencing were performed to identify the existence of a novel (TTTGA)n insertion. Targeted long-read sequencing was performed to confirm the accurate structure of the (TTTGA)n insertion. RESULTS: We identified a novel expanded intronic (TTTGA)n insertion at the same site as the previously reported (TTTCA)n insertion in SAMD12. This insertion cosegregated with familial cortical myoclonic tremor with epilepsy in 1 Chinese pedigree with no (TTTCA)n insertion. In the targeted long-read sequencing of 2 patients and 1 asymptomatic carrier in this pedigree, with 1 previously reported (TTTCA)n -insertion-carrying patient as a positive control, a respective total of 302, 159, 207, and 50 on-target subreads (predicated accuracy: ≥90%) spanning the target repeat expansion region were generated. These sequencing data revealed the accurate repeat expansion structures as (TTTTA)114-123 (TTTGA)108-116 in the pedigree and (TTTTA)38 (TTTCA)479 in (TTTCA)n -insertion-carrying patient. CONCLUSION: The targeted long-read sequencing helped us to elucidate the accurate structures of the (TTTGA)n and (TTTCA)n insertions. Our finding offers a novel possible cause for familial cortical myoclonic tremor with epilepsy and might shed light on the identification of genetic causes of this disease in pedigrees with no detected (TTTCA)n insertion in the reported causative genes. © 2019 International Parkinson and Movement Disorder Society.
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Epilepsias Mioclónicas/genética , Proteínas del Tejido Nervioso/genética , Temblor/genética , Adulto , Pueblo Asiatico , Epilepsias Mioclónicas/complicaciones , Humanos , Intrones/fisiología , Masculino , Linaje , Temblor/complicacionesRESUMEN
Familial cortical myoclonic tremor with epilepsy is an autosomal dominant neurodegenerative disease, characterized by cortical tremor and epileptic seizures. Although four subtypes (types 1-4) mapped on different chromosomes (8q24, 2p11.1-q12.2, 5p15.31-p15.1 and 3q26.32-3q28) have been reported, the causative gene has not yet been identified. Here, we report the genetic study in a cohort of 20 Chinese pedigrees with familial cortical myoclonic tremor with epilepsy. Linkage and haplotype analysis in 11 pedigrees revealed maximum two-point logarithm of the odds (LOD) scores from 1.64 to 3.77 (LOD scores in five pedigrees were >3.0) in chromosomal region 8q24 and narrowed the candidate region to an interval of 4.9 Mb. Using whole-genome sequencing, long-range polymerase chain reaction and repeat-primed polymerase chain reaction, we identified an intronic pentanucleotide (TTTCA)n insertion in the SAMD12 gene as the cause, which co-segregated with the disease among the 11 pedigrees mapped on 8q24 and additional seven unmapped pedigrees. Only two pedigrees did not contain the (TTTCA)n insertion. Repeat-primed polymerase chain reaction revealed that the sizes of (TTTCA)n insertion in all affected members were larger than 105 repeats. The same pentanucleotide insertion (ATTTCATTTC)58 has been reported to form RNA foci resulting in neurotoxicity in spinocerebellar ataxia type 37, which suggests the similar pathogenic process in familial cortical myoclonic tremor with epilepsy type 1.
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Epilepsias Mioclónicas/genética , Repeticiones de Microsatélite/genética , Proteínas del Tejido Nervioso/genética , Adulto , Anciano , Pueblo Asiatico , China , Mapeo Cromosómico , Epilepsias Mioclónicas/fisiopatología , Epilepsia/genética , Etnicidad/genética , Femenino , Ligamiento Genético , Haplotipos , Humanos , Intrones/genética , Masculino , Persona de Mediana Edad , Mutagénesis Insercional/genética , Proteínas del Tejido Nervioso/fisiología , Enfermedades Neurodegenerativas/genética , Linaje , Temblor/genéticaRESUMEN
Liquid biopsy by genotyping circulating tumor DNA (ctDNA) has provided a non-invasive approach in assessing tumor genomic alterations in clinical oncology. However, emerging evidence in clinical settings has shown significant discordance in the genomic alterations between matched tumor tissue and blood ctDNA samples, and even between the same set of blood samples analyzed on different testing platforms. Thus, it is necessary to study underlying causes of discrepancies in these studies by genotyping tumor tissue and ctDNA in parallel using next generation sequencing (NGS) panels based on the same technology. Here we enrolled 56 non-small-cell lung cancer (NSCLC) patients and evaluated tumor tissue genotyping and ctDNA based liquid biopsy by parallel NGS panel testing and compared different sample preparation conditions. Somatic mutations in plasma cell-free DNA (cfDNA) were detected in 63.6% patients with early-stage NSCLC and 60% patients with advanced-stage NSCLC. The overall concordance between matched formalin-fixed paraffin-embedded sample and cfDNA was 54.6% in early-stage NSCLC patients and 80% in advanced-stage NSCLC patients. The positive concordance rate was 44.4% and 71.4% in early-stage and advanced-stage patients, respectively. Using fresh frozen tumor samples did not improve the overall concordance rate between matched tumor tissue and cfDNA. Processing blood samples beyond 4 h after blood draw significantly decreased the detection rate of somatic mutations in cfDNA. Thus, the concordance rate between tumor tissue-based and ctDNA-based genotyping in clinical samples can be affected by multiple pre-analytical, analytical and biologic factors. Parallel NGS panel testing on both sample types for each patient may be warranted for effective guidance of cancer targeted therapies and possible early detection of cancer.
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Carcinoma de Pulmón de Células no Pequeñas/genética , ADN Tumoral Circulante/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias Pulmonares/genética , Mutación , Análisis de Secuencia de ADN/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Biopsia Líquida , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de NeoplasiasRESUMEN
Loss-of-function mutations in SGCE, which encodes ε-sarcoglycan (ε-SG), cause myoclonus-dystonia syndrome (OMIM159900, DYT11). A "major" ε-SG protein derived from CCDS5637.1 (NM_003919.2) and a "brain-specific" protein, that includes sequence derived from alternative exon 11b (CCDS47642.1, NM_001099400.1), are reportedly localized in post- and pre-synaptic membrane fractions, respectively. Moreover, deficiency of the "brain-specific" isoform and other isoforms derived from exon 11b may be central to the pathogenesis of DYT11. However, no animal model supports this hypothesis. Gene-trapped ES cells (CMHD-GT_148G1-3, intron 9 of NM_011360) were used to generate a novel Sgce mouse model (C57BL/6J background) with markedly reduced expression of isoforms derived from exons 3' to exon 9 of NM_011360. Among those brain regions analyzed in adult (2month-old) wild-type (WT) mice, cerebellum showed the highest relative expression of isoforms incorporating exon 11b. Homozygotes (SgceGt(148G1)Cmhd/Gt(148G1)Cmhd or SgceGt/Gt) and paternal heterozygotes (Sgcem+/pGt, m-maternal, p-paternal) showed 60 to 70% reductions in expression of total Sgce. Although expression of the major (NM_011360) and brain-specific (NM_001130189) isoforms was markedly reduced, expression of short isoforms was preserved and relatively small amounts of chimeric ε-SG/ß-galactosidase fusion protein was produced by the Sgce gene-trap locus. Immunoaffinity purification followed by mass spectrometry assessments of Sgcem+/pGt mouse brain using pan- or brain-specific ε-SG antibodies revealed significant reductions of ε-SG and other interacting sarcoglycans. Genome-wide gene-expression data using RNA derived from adult Sgcem+/pGt mouse cerebellum showed that the top up-regulated genes were involved in cell cycle, cellular development, cell death and survival, while the top down-regulated genes were associated with protein synthesis, cellular development, and cell death and survival. In comparison to WT littermates, Sgcem+/pGt mice exhibited "tiptoe" gait and stimulus-induced appendicular posturing between Postnatal Days 14 to 16. Abnormalities noted in older Sgcem+/pGt mice included reduced body weight, altered gait dynamics, and reduced open-field activity. Overt spontaneous or stimulus-sensitive myoclonus was not apparent on the C57BL/6J background or mixed C57BL/6J-BALB/c and C57BL/6J-129S2 backgrounds. Our data confirm that mouse Sgce is a maternally imprinted gene and suggests that short Sgce isoforms may compensate, in part, for deficiency of major and brain-specific Sgce isoforms.
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Encéfalo/metabolismo , Trastornos Distónicos/metabolismo , Sarcoglicanos/metabolismo , Animales , Ansiedad/metabolismo , Modelos Animales de Enfermedad , Conducta Exploratoria/fisiología , Femenino , Marcha/fisiología , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Actividad Motora/fisiología , Fenotipo , Isoformas de Proteínas/metabolismoRESUMEN
OBJECTIVE: Familial cortical myoclonic tremor with epilepsy is a rare epilepsy syndrome. Herein, we report on nine Chinese familial cortical myoclonic tremor with epilepsy pedigrees to delineate its clinical and neurophysiological features. METHODS: Detailed clinical and neurophysiological data were obtained. Somatosensory evoked potential amplitudes and clinical profile were analyzed using multilevel statistical models. Age-at-onset anticipation was analyzed using Kaplan-Meier survival analysis. RESULTS: Fifty-five patients were interviewed directly, whose mean age at onset of cortical tremor and generalized tonic-clonic seizures were 31.0 ± 8.3 and 36.0 ± 7.9 years. Giant somatosensory evoked potential was detected in 87.5% (28 of 32) of patients, and long-latency cortical reflex was detected in 93.5% (29 of 31). Cortical tremor severity was significantly higher in patients with longer disease duration of cortical tremor (P = 0.0061). Somatosensory evoked potential amplitudes were significant higher in patients with higher level of cortical tremor severity (P = 0.0003) and those using antiepileptic drugs (P = 0.0150). Age-at-onset anticipation of cortical tremor with paternal transmission was found with statistical significance (P = 0.022). CONCLUSION: We provided the clinical and neurophysiological features of familial cortical myoclonic tremor with epilepsy patients. This study is reported for the presentation of this rare disease in a Chinese population with the largest single report on familial cortical myoclonic tremor with epilepsy worldwide. Age-at-onset anticipation of cortical tremor with paternal transmission was statistically significant, which further confirmed a possibility of unstable expanding repeat in the genetic mechanism of familial cortical myoclonic tremor with epilepsy. © 2016 International Parkinson and Movement Disorder Society.
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Anticipación Genética , Corteza Cerebral/fisiopatología , Epilepsias Mioclónicas/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Adolescente , Adulto , Edad de Inicio , Anciano , China , Epilepsias Mioclónicas/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Adulto JovenRESUMEN
The vast majority of patients with primary dystonia are adults with focal or segmental distribution of involuntary movements. Although ~10% of probands have at least one first- or second-degree relative to dystonia, large families suited for linkage analysis are exceptional. After excluding mutations in known primary dystonia genes (TOR1A, THAP1 and CIZ1), whole-exome sequencing identified a GNAL missense mutation (c.682G>T, p.V228F) in an African-American pedigree with clinical phenotypes that include cervical, laryngeal and hand-forearm dystonia. Screening of 760 subjects with familial and sporadic primary dystonia identified three Caucasian pedigrees with GNAL mutations [c.591dupA (p.R198Tfs*13); c.733C>T (p.R245*); and c.3G>A (p.M1?)]. These mutations show incomplete penetrance. Our findings corroborate those of a recent study which used whole-exome sequencing to identify missense and nonsense GNAL mutations in Caucasian pedigrees of mixed European ancestry with mainly adult-onset cervical and segmental dystonia. GNAL encodes guanine nucleotide-binding protein G(olf), subunit alpha [Gα(olf)]. Gα(olf) plays a role in olfaction, coupling D1 and A2a receptors to adenylyl cyclase, and histone H3 phosphorylation. African-American subjects harboring the p.V228F mutation exhibited microsmia. Lymphoblastoid cell lines from subjects with the p.V228F mutation showed upregulation of genes involved in cell cycle control and development. Consistent with known sites of network pathology in dystonia, immunohistochemical studies indicated that Gα(olf) is highly expressed in the striatum and cerebellar Purkinje cells, and co-localized with corticotropin-releasing hormone receptors in the latter.
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Trastornos Distónicos/enzimología , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Adulto , Secuencia de Aminoácidos , Trastornos Distónicos/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP/química , Subunidades alfa de la Proteína de Unión al GTP/genética , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutación , Linaje , Alineación de Secuencia , Población Blanca/genéticaRESUMEN
Familial cortical myoclonic tremor with epilepsy (FCMTE) is an autosomal dominant epilepsy syndrome. Four loci, including 8q24 (FCMTE1), 2p11.1-q12.2 (FCMTE2), 5p15.31-p15.1 (FCMTE3), and 3q26.32-3q28 (FCMTE4) were previously reported. Herein, we report a new FCMTE1 pedigree from Chinese population with its clinical and genetic study results. Whole genome scan was performed to identify the causative gene region and copy number variants. Whole-exome sequencing was used to identify the causative gene. There were twelve affected members alive in this FCMTE1 pedigree. Nine affected members had both cortical myoclonic tremor and epilepsy, while three affected members had only cortical myoclonic tremor. Electrophysiologic examinations manifested giant somatosensory evoked potentials and long-latency cortical reflex in some affected members. Whole genome scan identified a 20.4 Mb causative gene region at 8q22.3-q24.13. No copy number variants were identified as the causative mutation. Whole-exome sequencing identified a co-segregated mutation (c.206A>T; p.Y69F) in the SLC30A8 gene. However, the evidence supporting this gene as the causative gene of FCMTE1 is not enough. We report the first Chinese FCMTE1 pedigree. No copy number variants, point mutation or small insertion/deletion were detected in the identified region that showed an association with FCMTE1. Further studies could focus on other possible genetic mechanisms while the association between the SLC30A8 and FCMTE1 needs further evidence.
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Epilepsias Mioclónicas/genética , Temblor Esencial/genética , Exoma , Adolescente , Adulto , Anciano , Pueblo Asiatico/genética , Mapeo Cromosómico , Variaciones en el Número de Copia de ADN , Femenino , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Linaje , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
The presence of oxidative stress in sperm cryopreservation induces sperm DNA damage. Our previous study has discovered that γH2AX, the DNA-damaged marker, was activated in the early mouse embryos fertilized with hydrogen peroxide (H2O2)-treated sperm. Furthermore, we found that checkpoint proteins ATM and Chk1 were phosphorylated and activated in the early mouse embryos. On the basis of previous researches, we examined the effects of sperm DNA damage on cell cycle arrest in mouse zygotes fertilized with H2O2-treated sperm. Development of fertilized eggs arrested at the PN disappearance stage. At 19 and 24 hours post-insemination (hpi), the percentage of zygotes at the PN disappearance stage was higher in H2O2-treated group compared to the control group. Immunofluorescence staining revealed Phospho-Cdc25C (Ser216) and Phospho-Cdc25B (Ser323) in or surrounding a single pronucleus, following insemination with H2O2-treated sperm. Our study suggests that fertilization with DNA-damaged sperm results in cell cycle arrest mediated by G2/M checkpoint activation in one of the pronuclei in mouse zygotes fertilized with H2O2-treated sperm; Phospho-Cdc25C and Phospho-Cdc25B correlate with activating G2/M checkpoint in zygotes fertilized with H2O2-treated sperm.
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Puntos de Control de la Fase G2 del Ciclo Celular/fisiología , Peróxido de Hidrógeno/farmacología , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Cigoto/metabolismo , Fosfatasas cdc25/metabolismo , Animales , Criopreservación/métodos , Daño del ADN , Femenino , Fertilización In Vitro , Masculino , Ratones , Fosforilación , Preservación de Semen , Cigoto/citologíaRESUMEN
Dystonia, a common and genetically heterogeneous neurological disorder, was recently defined as "a movement disorder characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both." Via the application of whole-exome sequencing, the genetic landscape of dystonia and closely related movement disorders is becoming exposed. In particular, several "novel" genetic causes have been causally associated with dystonia or dystonia-related disorders over the past 2 years. These genes include PRRT2 (DYT10), CIZ1 (DYT23), ANO3 (DYT24), GNAL (DYT25), and TUBB4A (DYT4). Despite these advances, major gaps remain in identifying the genetic origins for most cases of adult-onset isolated dystonia. Furthermore, model systems are needed to study the biology of PRRT2, CIZ1, ANO3, Gαolf, and TUBB4A in the context of dystonia. This review focuses on these recent additions to the family of dystonia genes, genotype-phenotype correlations, and possible cellular contributions of the encoded proteins to the development of dystonia.
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Trastornos Distónicos/genética , HumanosRESUMEN
In view of the conflicting data regarding the efficacy of the gonadotropin-releasing hormone (GnRH) antagonist/letrozole (A/L) protocol for treating poor responders undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), this systematic review and meta-analysis aimed to compare the effectiveness of the A/L protocol and the microdose GnRH agonist flare up (MF) protocol for such treatment. MEDLINE, EMBASE, Web of Science, and the China National Knowledge Infrastructure were searched for studies comparing the A/L and MF protocols for treating poor responders undergoing IVF/ICSI. We retrieved reports of three trials with data for 688 cycles in women. The clinical pregnancy rate was significantly decreased with the A/L compared with MF protocol (RR 0.70; 95% CI: 0.57-0.86; p = 0.001), the duration of gonadotrophin stimulation was lower with the A/L than MF protocol (MD -1.25; 95% CI: -2.37 to -0.12; p = 0.03). Moreover, there was no significant difference in cycle cancellation rate, number of oocytes retrieved, and the total dose of gonadotrophin between the two protocols. In conclusions, the clinical pregnancy rate may be lower with the A/L than MF protocol for treating poor responsers undergoing IVF/ICSI, but large-scale randomised controlled trials are needed to assess the A/L protocol.
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Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/administración & dosificación , Nitrilos/administración & dosificación , Inducción de la Ovulación/métodos , Triazoles/administración & dosificación , Femenino , Humanos , Letrozol , Masculino , Embarazo , Índice de Embarazo , Revisiones Sistemáticas como AsuntoRESUMEN
Cellular senescence is a crucial process of irreversible cell-cycle arrest, in which cells remain alive, but permanently unable to proliferate in response to distinct types of stressors. Accumulating evidence suggests that DNA damage builds over time and triggers DNA damage response signaling, leading to cellular senescence. Cellular senescence serves as a platform for the perpetuation of inflammatory responses and is central to numerous age-related diseases. Defects in DNA repair genes or senescence can cause premature aging disease. Therapeutic approaches limiting DNA damage or senescence contribute to a rescued phenotype of longevity and neuroprotection, thus suggesting a mechanistic interaction between DNA damage and senescence. Here, we offer a unique perspective on the crosstalk between the DNA damage response pathway and senescence as well as their contribution to age-related diseases. We further summarize recent progress on the mechanisms and therapeutics of senescence, address existing challenges, and offering new insights and future directions in the senescence field.
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Envejecimiento , Senescencia Celular , Daño del ADN , Reparación del ADN , Transducción de Señal , Humanos , Envejecimiento/metabolismo , Envejecimiento/genética , Animales , Susceptibilidad a EnfermedadesRESUMEN
Recently, a recurrent de novo dominant mutation in UBTF (c.628G>A, p.Glu210Lys; UBTF E210K) was identified as the cause of a neurological disorder which has been named UBTF Neuroregression Syndrome (UNS), or Childhood-Onset Neurodegeneration with Brain Atrophy (CONDBA). To date, only 17 cases have been reported worldwide. The molecular etiology is a pathogenic variant, E210K, within the HMG-box 2 of Upstream Binding Transcription Factor (UBTF). UBTF, a nucleolar protein, plays an important role in ribosomal RNA (rRNA) synthesis, nucleolar integrity, and cell survival. This variant causes unstable preinitiation complexes to form, resulting in altered rDNA chromatin structures, rRNA dysregulation, DNA damage, and ultimately, neurodegeneration. Defining clinical characteristics of the disorder include but are not limited to developmental regression beginning at approximately three years of age, progressive motor dysfunction, declining cognition, ambulatory loss, and behavioral problems. Histological and neuroimaging abnormalities include cortical atrophy, white matter deficits, and enlarged ventricles. Herein, we present a detailed overview of all published cases as well as the functional roles of UBTF to better understand the pathophysiology. Bringing undiagnosed cases to the attention of clinicians and researchers by making them aware of the clinical features will improve research and support the development of therapeutic interventions.
RESUMEN
BACKGROUND: Dystonia is a movement disorder characterized by involuntary sustained muscle contractions causing twisting and repetitive movements or abnormal postures. Some cases of primary and neurodegenerative dystonia have been associated with mutations in individual genes critical to the G1-S checkpoint pathway (THAP1, ATM, CIZ1 and TAF1). Secondary dystonia is also a relatively common clinical sign in many neurogenetic disorders. However, the contribution of structural variation in the genome to the etiopathogenesis of dystonia remains largely unexplored. CASE PRESENTATION: Cytogenetic analyses with the Affymetrix Genome-Wide Human SNP Array 6.0 identified a chromosome 13q34 duplication in a 36 year-old female with global developmental delay, facial dysmorphism, tall stature, breast cancer and dystonia, and her neurologically-normal father. Dystonia improved with bilateral globus pallidus interna (GPi) deep brain stimulation (DBS). Genomic breakpoint analysis, quantitative PCR (qPCR) and leukocyte gene expression were used to characterize the structural variant. The 218,345 bp duplication was found to include ADPRHL1, DCUN1D2, and TMCO3, and a 69 bp fragment from a long terminal repeat (LTR) located within Intron 3 of TFDP1. The 3' breakpoint was located within Exon 1 of a TFDP1 long non-coding RNA (NR_026580.1). In the affected subject and her father, gene expression was higher for all three genes located within the duplication. However, in comparison to her father, mother and neurologically-normal controls, the affected subject also showed marked overexpression (2×) of the transcription factor TFDP1 (NM_007111.4). Whole-exome sequencing identified an SGCE variant (c.1295G > A, p.Ser432His) that could possibly have contributed to the development of dystonia in the proband. No pathogenic mutations were identified in BRCA1 or BRCA2. CONCLUSION: Overexpression of TFDP1 has been associated with breast cancer and may also be linked to the tall stature, dysmorphism and dystonia seen in our patient.
Asunto(s)
Anomalías Múltiples/genética , Neoplasias de la Mama/genética , Cromosomas Humanos Par 13 , Distonía/genética , Discapacidad Intelectual/genética , Atrofia Muscular/genética , Factor de Transcripción DP1/genética , Adulto , Duplicación Cromosómica/genética , Cromosomas Humanos Par 13/genética , Anomalías Craneofaciales , Discapacidades del Desarrollo/genética , Facies , Femenino , Regulación de la Expresión Génica/genética , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Trastornos Psicóticos/genéticaRESUMEN
OBJECTIVE: Primary dystonia is usually of adult onset, can be familial, and frequently involves the cervical musculature. Our goal was to identify the causal mutation in a family with adult onset, primary cervical dystonia. METHODS: Linkage and haplotype analyses were combined with solution-based whole-exome capture and massively parallel sequencing in a large Caucasian pedigree with adult onset, primary cervical dystonia to identify a cosegregating mutation. High-throughput screening and Sanger sequencing were completed in 308 Caucasians with familial or sporadic adult onset cervical dystonia and matching controls for sequence variants in this mutant gene. RESULTS: Exome sequencing led to the identification of an exonic splicing enhancer mutation in exon 7 of CIZ1 (c.790A>G, p.S264G), which encodes CIZ1, Cip1-interacting zinc finger protein 1. CIZ1 is a p21(Cip1/Waf1) -interacting zinc finger protein expressed in brain and involved in DNA synthesis and cell-cycle control. Using a minigene assay, we showed that c.790A>G altered CIZ1 splicing patterns. The p.S264G mutation also altered the nuclear localization of CIZ1. Screening in subjects with adult-onset cervical dystonia identified 2 additional CIZ1 missense mutations (p.P47S and p.R672M). INTERPRETATION: Mutations in CIZ1 may cause adult onset, primary cervical dystonia, possibly by precipitating neurodevelopmental abnormalities that manifest in adults and/or G1/S cell-cycle dysregulation in the mature central nervous system.