RESUMEN
Cell cycle regulatory enzyme Pin1 both catalyzes pSer/Thr-cis/trans-Pro isomerization and binds the same motif separately in its WW domain. To better understand the function of Pin1, a way to separate these activities is needed. An unnatural peptide library, R1CO-pSer-Pro-NHR2, was designed to identify ligands specific for the Pin1 WW domain. A new solid-phase phosphorylating reagent (SPPR) containing a phosphoramidite functional group was synthesized in one step from Wang resin. The SPPR was used in the preparation of the library by parallel synthesis. The final 315-member library was screened with our WW-domain-specific, enzyme-linked enzyme-binding assay (ELEBA). Four of the best hits were resynthesized, and the competitive dissociation constants were measured by ELEBA. NMR chemical-shift perturbations (CSP) of ligands with 15N-labeled Pin1 were used to measure Kd for the best four ligands directly, demonstrating that they were specific Pin1 WW domain ligands. Models of the ligands bound to the Pin1 WW domain were used to visualize the mode of binding in the WW domain.
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We report the cases of two Spanish pediatric patients with hypotonia, muscle weakness and feeding difficulties at birth. Whole-exome sequencing (WES) uncovered two new homozygous VAMP1 (Vesicle Associated Membrane Protein 1) splicing variants, NM_014231.5:c.129+5 G > A in the boy patient (P1) and c.341-24_341-16delinsAGAAAA in the girl patient (P2). This gene encodes the vesicle-associated membrane protein 1 (VAMP1) that is a component of a protein complex involved in the fusion of synaptic vesicles with the presynaptic membrane. VAMP1 has a highly variable C-terminus generated by alternative splicing that gives rise to three main isoforms (A, B and D), being VAMP1A the only isoform expressed in the nervous system. In order to assess the pathogenicity of these variants, expression experiments of RNA for VAMP1 were carried out. The c.129+5 G > A and c.341-24_341-16delinsAGAAAA variants induced aberrant splicing events resulting in the deletion of exon 2 (r.5_131del; p.Ser2TrpfsTer7) in the three isoforms in the first case, and the retention of the last 14 nucleotides of the 3' of intron 4 (r.340_341ins341-14_341-1; p.Ile114AsnfsTer77) in the VAMP1A isoform in the second case. Pathogenic VAMP1 variants have been associated with autosomal dominant spastic ataxia 1 (SPAX1) and with autosomal recessive presynaptic congenital myasthenic syndrome (CMS). Our patients share the clinical manifestations of CMS patients with two important differences: they do not show the typical electrophysiological pattern that suggests pathology of pre-synaptic neuromuscular junction, and their muscular biopsies present hypertrophic fibers type 1. In conclusion, our data expand both genetic and phenotypic spectrum associated with VAMP1 variants.
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Homocigoto , Síndromes Miasténicos Congénitos , Fenotipo , Proteína 1 de Membrana Asociada a Vesículas , Femenino , Humanos , Masculino , Empalme Alternativo/genética , Secuenciación del Exoma , Mutación , Síndromes Miasténicos Congénitos/genética , Síndromes Miasténicos Congénitos/patología , Isoformas de Proteínas/genética , Empalme del ARN/genética , Proteína 1 de Membrana Asociada a Vesículas/genética , Lactante , PreescolarRESUMEN
BACKGROUND: Up to 7% of patients with Duchenne muscular dystrophy (DMD) or Becker muscular dystrophy (BMD) remain genetically undiagnosed after routine genetic testing. These patients are thought to carry deep intronic variants, structural variants or splicing alterations not detected through multiplex ligation-dependent probe amplification or exome sequencing. METHODS: RNA was extracted from seven muscle biopsy samples of patients with genetically undiagnosed DMD/BMD after routine genetic diagnosis. RT-PCR of the DMD gene was performed to detect the presence of alternative transcripts. Droplet digital PCR and whole-genome sequencing were also performed in some patients. RESULTS: We identified an alteration in the mRNA level in all the patients. We detected three pseudoexons in DMD caused by deep intronic variants, two of them not previously reported. We also identified a chromosomal rearrangement between Xp21.2 and 8p22. Furthermore, we detected three exon skipping events with unclear pathogenicity. CONCLUSION: These findings indicate that mRNA analysis of the DMD gene is a valuable tool to reach a precise genetic diagnosis in patients with a clinical and anatomopathological suspicion of dystrophinopathy that remain genetically undiagnosed after routine genetic testing.
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Distrofia Muscular de Duchenne , Humanos , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Distrofina/genética , ARN Mensajero/genética , Mutación , Reacción en Cadena de la Polimerasa MultiplexRESUMEN
BACKGROUND: Limb-girdle muscular dystrophies (LGMD) are a heterogeneous group of genetically determined muscle disorders. TRAPPC11-related LGMD is an autosomal-recessive condition characterised by muscle weakness and intellectual disability. METHODS: A clinical and histopathological characterisation of 25 Roma individuals with LGMD R18 caused by the homozygous TRAPPC11 c.1287+5G>A variant is reported. Functional effects of the variant on mitochondrial function were investigated. RESULTS: The c.1287+5G>A variant leads to a phenotype characterised by early onset muscle weakness, movement disorder, intellectual disability and elevated serum creatine kinase, which is similar to other series. As novel clinical findings, we found that microcephaly is almost universal and that infections in the first years of life seem to act as triggers for a psychomotor regression and onset of seizures in several individuals with TRAPPC11 variants, who showed pseudometabolic crises triggered by infections. Our functional studies expanded the role of TRAPPC11 deficiency in mitochondrial function, as a decreased mitochondrial ATP production capacity and alterations in the mitochondrial network architecture were detected. CONCLUSION: We provide a comprehensive phenotypic characterisation of the pathogenic variant TRAPPC11 c.1287+5G>A, which is founder in the Roma population. Our observations indicate that some typical features of golgipathies, such as microcephaly and clinical decompensation associated with infections, are prevalent in individuals with LGMD R18.
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Discapacidad Intelectual , Microcefalia , Distrofia Muscular de Cinturas , Distrofias Musculares , Romaní , Humanos , Romaní/genética , Fenotipo , Distrofia Muscular de Cinturas/genética , Debilidad Muscular , Proteínas de Transporte VesicularRESUMEN
3D-printing technology allows scientist to fabricate easily electrochemical sensors. Until now, these sensors were designed employing a large amount of material, which increases the cost and decreases manufacturing throughput. In this work, a low-cost 3D-printed on-drop electrochemical sensor (3D-PES) was fully manufactured by fused filament fabrication, minimizing the number of printing layers. Carbon black/polylactic acid filament was employed, and the design and several printing parameters were optimized to yield the maximum electroanalytical performance using the minimal amount of material. Print speed and extrusion width showed a critical influence on the electroanalytical performance of 3D-PES. Under optimized conditions, the fabrication procedure offered excellent reproducibility (RSD 1.3% in working electrode diameter), speed (< 3 min/unit), and costs (< 0.01 $ in material cost). The 3D-PES was successfully applied to the determination of phloridzin in apple juice. The analytical performance of 3D-PES was compared with an equivalent commercial on-drop screen-printed electrode, yielding similar precision and accuracy but lower sensitivity. However, 3D-PES provides interesting features such as recyclability, biodegradability, low-cost, and the possibility of being manufactured near the point of need, some of which meets several demands of Green Chemistry. This cost-effective printing approach is a green and promising alternative for manufacturing disposable and portable electroanalytical devices, opening new possibilities not only in on-site food analysis but also in point-of-care testing.
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Técnicas Electroquímicas , Análisis de los Alimentos , Jugos de Frutas y Vegetales , Poliésteres , Impresión Tridimensional , Hollín , Hollín/química , Poliésteres/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/economía , Jugos de Frutas y Vegetales/análisis , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/economía , Análisis de los Alimentos/métodos , Electrodos , Malus/química , Análisis Costo-Beneficio , Límite de DetecciónRESUMEN
N-type voltage-gated calcium channel controls the release of neurotransmitters from neurons. The association of other voltage-gated calcium channels with epilepsy is well-known. The association of N-type voltage-gated calcium channels and pain has also been established. However, the relationship between this type of calcium channel and epilepsy has not been specifically reviewed. Therefore, the present review systematically summarizes existing publications regarding the genetic associations between N-type voltage-dependent calcium channel and epilepsy.
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Canales de Calcio Tipo N , Epilepsia , Síndromes Epilépticos , Humanos , Calcio/metabolismo , Epilepsia/genética , Neuronas/metabolismoRESUMEN
Mechanical thrombectomy (MT) in pediatric stroke is supported by studies in adults, but there is controversy regarding younger patients. The main growth of intracranial vessels occurs up to 2 years when there can be more difficulties in MT.Description of the MT performed in a 2-month-old patient-the youngest infant published to date. We also review the literature on MT for stroke in infants.A 2-month-old patient presented with an awakening stroke secondary to an occlusion of the M1 segment of the left middle cerebral artery. A successful MT was performed with an aspiration device without clinically significant complications. An etiological study was completed, and neuroimaging showed focal cerebral arteriopathy. The 3-month outcome was excellent: the pediatric modified Rankin score was 0.Including this case, MT for acute stroke has been reported in only 10 infants. MT was successful in 90%, mostly using adult conventional stent retrievers. There were complications only in patients with mechanical circulatory support (MCS) devices; three patients died due to hemorrhagic transformation after MT and one patient died due to recurrent ischemic stroke.MT seems effective and safe in infants similarly to other pediatric ages. In children under 2 years of age, the presence of comorbidities requiring MCS devices is the main factor underlying poor prognosis.
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Isquemia Encefálica , Accidente Cerebrovascular , Adulto , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/cirugía , Niño , Humanos , Lactante , Neuroimagen , Estudios Retrospectivos , Stents , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Resultado del TratamientoRESUMEN
STUDY OBJECTIVE: To determine the feasibility of intravenous indocyanine green (ICG) dye use in patients with adnexal torsion to intraoperatively evaluate ovarian perfusion after detorsion. DESIGN: A prospective multicenter single-arm feasibility study. SETTING: A teaching hospital. PATIENTS: A total of 12 nonpregnant patients, 18 to 45 years old with surgically confirmed adnexal torsion. INTERVENTIONS: Torsion was surgically confirmed, the involved adnexa were untwisted laparoscopically, and ICG dye was injected intravenously. The absence or presence of ICG perfusion was documented, and the clinical decision for ovarian conservation or removal was determined by the surgeon. MEASUREMENTS AND MAIN RESULTS: The primary outcome was feasibility of using ICG dye including measures such as time to visualized perfusion and operative time. Secondary outcomes included presence or absence of ovarian preservation and postoperative follow-up measures. Intraoperative visualization of ICG perfusion to the detorsed adnexa was achieved in 10 patients (83%) in a median time of 1 minute (0, 2), resulting in entire (n = 9) or partial (n = 1) ovarian conservation. Perfusion was absent in 2 cases, and postoophorectomy histologic necrosis was confirmed in one case. Median operative time was 74 minutes (48, 94). There were no adverse events related to ICG dye use. CONCLUSION: Intraoperative ICG dye use in this study was logistically feasible and conservation of the entire or partial ovary was observed in 83% of patients, including one case where preoperative Doppler flow was absent.
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Verde de Indocianina , Torsión Ovárica , Anexos Uterinos , Adolescente , Adulto , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Adulto JovenRESUMEN
Epilepsy is a neurological disorder that affects more than 50 million people. Its etiology is unknown in approximately 60% of cases, although the existence of a genetic factor is estimated in about 75% of these individuals. Hundreds of genes involved in epilepsy are known, and their number is increasing progressively, especially with next-generation sequencing techniques. However, there are still many cases in which the results of these molecular studies do not fully explain the phenotype of the patients. Somatic mutations specific to brain tissue could contribute to the phenotypic spectrum of epilepsy. Undetectable in the genomic DNA of blood cells, these alterations can be identified in cell-free DNA (cfDNA). We aim to review the current literature regarding the detection of somatic variants in cfDNA to diagnose refractory epilepsy, highlighting novel research directions and suggesting further studies.
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Ácidos Nucleicos Libres de Células , Epilepsia Refractaria , Epilepsia , Encéfalo , Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/genética , Epilepsia Refractaria/diagnóstico , Epilepsia Refractaria/genética , Epilepsia/diagnóstico , Epilepsia/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , MutaciónRESUMEN
Holt-Oram syndrome (HOS) is a rare disorder characterized by cardiac and upper-limb defects. Pathogenic variants in TBX5-a gene encoding a transcription factor important for heart and skeletal development-are the only known cause of HOS. Here, we present the identification and functional analysis of two novel TBX5 pathogenic variants found in two individuals with HOS presenting distinct phenotypes. The individual with the c.905delA variant has a severe cardiac phenotype but mild skeletal defects, unlike the individual with the c.246_249delGATG variant who has no cardiac problems but severe upper limbs malformations, including phocomelia. Both frameshift variants, c.246_249delGATG and c.905delA, generate mRNAs harbouring premature stop codons which, if not degraded by nonsense mediated decay, will lead to the production of shorter TBX5 proteins, p.Gln302Argfs*92 and p.Met83Phefs*6, respectively. Immunocytochemistry results suggest that both mutated proteins are produced and furthermore, like the wild-type protein, p.Gln302Argfs*92 mutant appears to be mainly localized in the nucleus, in contrast with p.Met83Phefs*6 mutant that displays a higher level of cytoplasmic localization. In addition, luciferase activity analysis revealed that none of the TBX5 mutants are capable of transactivating the NPPA promoter. In conclusion, our results provide evidence that both pathogenic variants cause a severe TBX5 loss-of-function, dramatically reducing its biological activity. The absence of cardiac problems in the individual with the p.Met83Phefs*6 variant supports the existence of other mechanisms/genes underlying the pathogenesis of HOS and/or the existence of an age-related delay in the development of a more serious cardiac phenotype. Further studies are required to understand the differential effects observed in the phenotypes of both individuals.
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Anomalías Múltiples/genética , Anomalías Múltiples/patología , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Defectos del Tabique Interatrial/genética , Defectos del Tabique Interatrial/patología , Deformidades Congénitas de las Extremidades Inferiores/genética , Deformidades Congénitas de las Extremidades Inferiores/patología , Proteínas de Dominio T Box/genética , Deformidades Congénitas de las Extremidades Superiores/genética , Deformidades Congénitas de las Extremidades Superiores/patología , Adulto , Anciano de 80 o más Años , Células Cultivadas , Análisis Citogenético , Análisis Mutacional de ADN , Estudios de Asociación Genética , Heterogeneidad Genética , Células HEK293 , Humanos , Masculino , Mutación/fisiología , Fenotipo , Proteínas de Dominio T Box/fisiologíaRESUMEN
BACKGROUND: The scientific publications of antimicrobial susceptibilities and resistance must be precise, with interpretations adjusted to the standard. In this frame, knowledge of antimicrobial resistance is fundamental in pathogenic microorganisms such as Salmonella spp., known for many annual deaths worldwide. The objective of this work was to compare the interpretation of standards, the concentrations, and the breakpoints, to study antimicrobial resistance in Non-Typhoidal Salmonella (NTS) isolated from beef, pork, and chicken meat, meat products, and propose additional considerations that improve the use and usefulness of published results. RESULTS: After refining the search based on meeting the inclusion and exclusion criteria, 48 papers were selected. In 33 (68.8%) of them, the disc diffusion method was used, in 11 (22.9%) the MIC determination method, and in 4 (8.33%) were used both. In 24 (50%) of the articles, the selection of a different (correct) standard could have had an impact on the interpretation of antimicrobial susceptibility, which observed when considering three scenarios, i) comparison between the year of the isolation versus the implemented standard, ii) comparison between the year of submission versus implemented standard and iii) comparison between the year of publication versus implemented standard. CONCLUSIONS: The most frequent scenario was the inadequate selection of standards, indicating that some studies had not ensured that applied standards kept in line with the date of isolation, date of publication and interpretation of susceptibilities. We proposed 2 years for standards use for resistance and multi-resistance interpretations. On the other hand, we invite researchers to publish their results in the shortest possible time, and editors and reviewers of scientific journals to prioritise these types of studies and verify the correspondence between the standard cited and the one used and the one to be taken into account.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Productos de la Carne/microbiología , Carne/microbiología , Salmonella/efectos de los fármacos , Salmonella/fisiología , Animales , Pruebas de Sensibilidad MicrobianaRESUMEN
Latin America (LATAM) children offer special insight into Severe Acute Respiratory Syndrome Coronavirus 2 (SARS COV2) due to high-risk race/ethnicity, variability in medical resources, diverse socioeconomic background, and numerous involved organ systems. This multinational study of LATAM youth examined the distinguishing features of acute or late multisystem SARS COV2 with versus without cardiac involvement. A consecutive sample of youth 0-18 years old (N = 98;50% male) presenting with multisystem SARS COV2 to 32 centers in 10 Latin American countries participating in a pediatric cardiac multi-imaging society were grouped as with versus without cardiac involvement, defined as abnormal echocardiographic findings or arrhythmia. Collected clinical data were analyzed by Student's t-test or Fisher's exact test. Cardiac (N = 48, 50% male) versus no cardiac (N = 50, 50% male) were similar in age; weight; nonrespiratory symptoms; and medical history. The cardiac group had 1 death and symptoms including coronary artery dilation, ejection fraction <50%, pericardial effusion, peripheral edema, arrhythmia, and pulmonary artery thrombus. The cardiac group had higher risk of ICU admission (77% vs 54%, p = 0.02); invasive ventilation (23% vs 4%,p = 0.007); vasoactive infusions (27% vs 4%, p = 0.002); prominent respiratory symptoms (60% vs 36%, p < 0.03); abnormal chest imaging (69% vs 34%, p = 0.001); troponin (33% vs 12%, p = 0.01); alanine aminotransferase (33% vs 12%, p = 0.02); and thrombocytopenia (46% vs 22%, p = 0.02). Receiver operating curve analysis showed that abnormal laboratories had 94% sensitivity and 98% negative predictive value on the need for ICU interventions.Conclusion: In LATAM children with multisystem SARS COV2, cardiac involvement was prevalent. Cardiac involvement was more likely to require ICU interventions, certain abnormal labs, and respiratory involvement. What is Known: ⢠SARS COV2 can be asymptomatic in children but in some cases can have serious multisystemic involvement. ⢠Hispanic ethnicity is purportedly at high risk of SARS COV2 in nations where they are often disadvantaged minority populations. What is New: ⢠Latin American children presenting with multisystem SARS COV2 frequently have cardiac involvement which was associated with ICU interventions; prominent respiratory symptoms; abnormal chest X-ray; elevated troponin, ALT, and thrombocytopenia. ⢠Elevated troponin, ALT or thrombocytopenia had high sensitivity and negative predictive value on the need for intensive care interventions.
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COVID-19 , SARS-CoV-2 , Adolescente , Arritmias Cardíacas , Niño , Preescolar , Cuidados Críticos , Femenino , Humanos , Lactante , Recién Nacido , América Latina/epidemiología , MasculinoRESUMEN
Eyelid myoclonia with absences (EMA), also known as Jeavons syndrome (JS) is a childhood onset epileptic syndrome with manifestations involving a clinical triad of absence seizures with eyelid myoclonia (EM), photosensitivity (PS), and seizures or electroencephalogram (EEG) paroxysms induced by eye closure. Although a genetic contribution to this syndrome is likely and some genetic alterations have been defined in several cases, the genes responsible for have not been identified. In this review, patients diagnosed with EMA (or EMA-like phenotype) with a genetic diagnosis are summarized. Based on this, four genes could be associated to this syndrome (SYNGAP1, KIA02022/NEXMIF, RORB, and CHD2). Moreover, although there is not enough evidence yet to consider them as candidate for EMA, three more genes present also different alterations in some patients with clinical diagnosis of the disease (SLC2A1, NAA10, and KCNB1). Therefore, a possible relationship of these genes with the disease is discussed in this review.
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Epilepsia Tipo Ausencia/genética , Enfermedades Genéticas Congénitas/genética , Mioclonía/genética , HumanosRESUMEN
OBJECTIVE: Comprehensive clinical characterization of congenital titinopathy to facilitate diagnosis and management of this important emerging disorder. METHODS: Using massively parallel sequencing we identified 30 patients from 27 families with 2 pathogenic nonsense, frameshift and/or splice site TTN mutations in trans. We then undertook a detailed analysis of the clinical, histopathological and imaging features of these patients. RESULTS: All patients had prenatal or early onset hypotonia and/or congenital contractures. None had ophthalmoplegia. Scoliosis and respiratory insufficiency typically developed early and progressed rapidly, whereas limb weakness was often slowly progressive, and usually did not prevent independent walking. Cardiac involvement was present in 46% of patients. Relatives of 2 patients had dilated cardiomyopathy. Creatine kinase levels were normal to moderately elevated. Increased fiber size variation, internalized nuclei and cores were common histopathological abnormalities. Cap-like regions, whorled or ring fibers, and mitochondrial accumulations were also observed. Muscle magnetic resonance imaging showed gluteal, hamstring and calf muscle involvement. Western blot analysis showed a near-normal sized titin protein in all samples. The presence of 2 mutations predicted to impact both N2BA and N2B cardiac isoforms appeared to be associated with greatest risk of cardiac involvement. One-third of patients had 1 mutation predicted to impact exons present in fetal skeletal muscle, but not included within the mature skeletal muscle isoform transcript. This strongly suggests developmental isoforms are involved in the pathogenesis of this congenital/early onset disorder. INTERPRETATION: This detailed clinical reference dataset will greatly facilitate diagnostic confirmation and management of patients, and has provided important insights into disease pathogenesis. Ann Neurol 2018;83:1105-1124.
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Cardiomiopatía Dilatada/congénito , Conectina/genética , Proteínas Musculares/genética , Músculo Esquelético/patología , Femenino , Humanos , Masculino , Mutación/genética , Fenotipo , Isoformas de Proteínas/genéticaRESUMEN
In two siblings, who suffer from an early childhood-onset axonal polyneuropathy with exclusive involvement of motor fibers, the c.629T>C (p.F210S) mutation was identified in the X-linked AIFM1 gene, which encodes for the apoptosis-inducing factor (AIF). The mutation was predicted as deleterious, according to in silico analysis. A decreased expression of the AIF protein, altered cellular morphology, and a fragmented mitochondrial network were observed in the proband's fibroblasts. This new form of motor neuropathy expands the phenotypic spectrum of AIFM1 mutations and therefore, the AIFM1 gene should be considered in the diagnosis of hereditary motor neuropathies.
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Factor Inductor de la Apoptosis/genética , Atrofia Muscular Espinal/genética , Mutación/genética , Femenino , Genes Ligados a X/genética , Humanos , Lactante , Masculino , Atrofia Muscular Espinal/diagnóstico , Linaje , Fenotipo , Proteínas/genéticaRESUMEN
We report the clinical and biochemical findings from two unrelated patients who presented with a novel syndrome: encephalopathy, intellectual disability, severe hypotonia, chorea and optic atrophy. Whole exome sequencing (WES) uncovered a homozygous mutation in the ATP8A2 gene (NM_016529:c.1287G > T, p.K429N) in one patient and compound heterozygous mutations (c.1630G > C, p.A544P and c.1873C > T, p.R625W) in the other. Only one haploinsufficiency case and a family with a homozygous mutation in ATP8A2 gene (c.1128C > G, p.I376M) have been described so far, with phenotypes that differed slightly from the patients described herein. In conclusion, our data expand both the genetic and phenotypic spectrum associated with ATP8A2 gene mutations.
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Adenosina Trifosfatasas/genética , Encefalopatías/genética , Corea/genética , Discapacidad Intelectual/genética , Hipotonía Muscular/genética , Mutación , Atrofia Óptica/genética , Proteínas de Transferencia de Fosfolípidos/genética , Encefalopatías/complicaciones , Niño , Preescolar , Corea/complicaciones , Femenino , Homocigoto , Humanos , Discapacidad Intelectual/complicaciones , Hipotonía Muscular/complicaciones , Atrofia Óptica/complicaciones , Linaje , Síndrome , Secuenciación del ExomaRESUMEN
The DNA amplification performed by terminal protein-primed replication systems has not yet been developed for its general use to produce high amounts of DNA linked to terminal protein (TP). Here we present a method to amplify in vitro heterologous DNAs using the Φ29 DNA replication machinery and producing DNA with TP covalently attached to the 5' end. The amplification requires four Φ29 proteins, DNA polymerase, TP, single-stranded DNA binding protein and double-stranded DNA binding protein (p6). The DNA to be amplified is inserted between two sequences that are the Φ29 DNA replication origins, consisting of 191 and 194 bp from the left and right ends of the phage genome, respectively. The replication origins do not need to have TP covalently attached beforehand to be functional in amplification and they can be joined to the DNA to be amplified by cloning or ligation. The facts that two functional origins were required at the ends of a linear template DNA and that the kinetics of DNA synthesis was very similar to that obtained using the TP-containing Φ29 genome as template support the proposal that genuine amplification is taking place. Amplification factors of 30-fold have been obtained. Possible applications of DNAs produced by this method are discussed.
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Fagos de Bacillus/genética , ADN Viral/genética , ADN/genética , Bacillus/virología , Secuencia de Bases , Replicación del ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Genoma Viral , Cinética , Modelos Genéticos , Datos de Secuencia Molecular , Oligonucleótidos/genética , Plásmidos/metabolismo , Origen de RéplicaRESUMEN
Pin1 is a modular enzyme that accelerates the cis-trans isomerization of phosphorylated-Ser/Thr-Pro (pS/T-P) motifs found in numerous signaling proteins regulating cell growth and neuronal survival. We have used NMR to investigate the interaction of Pin1 with three related ligands that include a pS-P substrate peptide, and two pS-P substrate analogue inhibitors locked in the cis and trans conformations. Specifically, we compared the ligand binding modes and binding-induced changes in Pin1 side-chain flexibility. The cis and trans binding modes differ, and produce different mobility in Pin1. The cis-locked inhibitor and substrate produced a loss of side-chain flexibility along an internal conduit of conserved hydrophobic residues, connecting the domain interface with the isomerase active site. The trans-locked inhibitor produces a weaker conduit response. Thus, the conduit response is stereoselective. We further show interactions between the peptidyl-prolyl isomerase and Trp-Trp (WW) domains amplify the conduit response, and alter binding properties at the remote peptidyl-prolyl isomerase active site. These results suggest that specific input conformations can gate dynamic changes that support intraprotein communication. Such gating may help control the propagation of chemical signals by Pin1, and other modular signaling proteins.
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Isomerasa de Peptidilprolil/química , Isomerasa de Peptidilprolil/metabolismo , Secuencias de Aminoácidos , Unión Competitiva , Fenómenos Biofísicos , Dominio Catalítico , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Técnicas In Vitro , Modelos Moleculares , Peptidilprolil Isomerasa de Interacción con NIMA , Resonancia Magnética Nuclear Biomolecular , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Isomerasa de Peptidilprolil/genética , Fosforilación , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Electricidad Estática , Estereoisomerismo , Especificidad por SustratoRESUMEN
This work presents a hybrid (experimental-computational) application for improving the vibration behavior of structural components using a lightweight multilayer composite. The vibration behavior of a flat steel plate has been improved by the gluing of a lightweight composite formed by a core of polyurethane foam and two paper mats placed on its faces. This composite enables the natural frequencies to be increased and the modal density of the plate to be reduced, moving about the natural frequencies of the plate out of excitation range, thereby improving the vibration behavior of the plate. A specific experimental model for measuring the Operating Deflection Shape (ODS) has been developed, which enables an evaluation of the goodness of the natural frequencies obtained with the computational model simulated by the finite element method (FEM). The model of composite + flat steel plate determined by FEM was used to conduct parametric study, and the most influential factors for 1st, 2nd and 3rd mode were identified using a multifactor analysis of variance (Multifactor-ANOVA). The presented results can be easily particularized for other cases, as it may be used in cycles of continuous improvement as well as in the product development at the material, piece, and complete-system levels.
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Background: We report the first finding of Bathynellacea, discovered in Mongolia. We also report a new species of the genus Altainella Camacho, 2020, which was previously recorded only in the western edge of Russia. New information: Altainellamongoliensis sp. nov. was found in the interstitial hyporheic region of the Onon River Basin, Mongolia, by inserting a core approximately 1.2 m deep and extracting the underground interstitial water. The new species exhibited sexual dimorphism in thoracopod VII, uniquely observed within the genus Altainella. We provide a morphological description and remarks on the new species with molecular information based on the 18S rDNA and partial CO1 gene sequences. We emphasise the need for continued research on the subterranean biodiversity in previously neglected regions by reporting the first discovery of macro-stygobionts in Mongolia.