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1.
Bio Protoc ; 14(16): e5048, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39210952

RESUMEN

Generating protein conjugates using the bioorthogonal ligation between tetrazines and trans-cyclooctene groups avoids the need to manipulate cysteine amino acids; this ligation is rapid, site-specific, and stoichiometric and allows for labeling of proteins in complex biological environments. Here, we provide a protocol for the expression of conjugation-ready proteins at high yields in Escherichia coli with greater than 95% encoding and labeling fidelity. This protocol focuses on installing the Tet2 tetrazine amino acid using an optimized genetic code expansion (GCE) machinery system, Tet2 pAJE-E7, to direct Tet2 encoding at TAG stop codons in BL21 E. coli strains, enabling reproducible expression of Tet2-proteins that quantitatively react with trans-cyclooctene (TCO) groups within 5 min at room temperature and physiological pH. The use of the BL21 derivative B95(DE3) minimizes premature truncation byproducts caused by incomplete suppression of TAG stop codons, which makes it possible to use more diverse protein construct designs. Here, using a superfolder green fluorescent protein construct as an example protein, we describe in detail a four-day process for encoding Tet2 with yields of ~200 mg per liter of culture. Additionally, a simple and fast diagnostic gel electrophoretic mobility shift assay is described to confirm Tet2-Et encoding and reactivity. Finally, strategies are discussed to adapt the protocol to alternative proteins of interest and optimize expression yields and reactivity for that protein. Key features • Protocol describes site-specific encoding of the tetrazine amino acid Tet2-Et into proteins for bioorthogonal, quantitative, and rapid attachment of trans-cyclooctene-containing labels. • Protocol uses auto-induction methods for the production Tet2-Et protein in E. coli. • This protocol focuses on Tet-protein expressions in BL21(DE3) and B95(DE3) strains, which take approximately 4 days to complete. • SDS-PAGE mobility shift assay using a strained TCO-PEG5000 (sTCO-PEG5000) reagent provides a simple, generalizable method for testing Tet-protein reactivity.

2.
Front Immunol ; 15: 1423510, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38975338

RESUMEN

Over the course of evolution, many proteins have undergone adaptive structural changes to meet the increasing homeostatic regulatory demands of multicellularity. Aminoacyl tRNA synthetases (aaRS), enzymes that catalyze the attachment of each amino acid to its cognate tRNA, are such proteins that have acquired new domains and motifs that enable non-canonical functions. Through these new domains and motifs, aaRS can assemble into large, multi-subunit complexes that enhance the efficiency of many biological functions. Moreover, because the complexity of multi-aminoacyl tRNA synthetase (mARS) complexes increases with the corresponding complexity of higher eukaryotes, a contribution to regulation of homeostatic functions in multicellular organisms is hypothesized. While mARS complexes in lower eukaryotes may enhance efficiency of aminoacylation, little evidence exists to support a similar role in chordates or other higher eukaryotes. Rather, mARS complexes are reported to regulate multiple and variegated cellular processes that include angiogenesis, apoptosis, inflammation, anaphylaxis, and metabolism. Because all such processes are critical components of immune homeostasis, it is important to understand the role of mARS complexes in immune regulation. Here we provide a conceptual analysis of the current understanding of mARS complex dynamics and emerging mARS complex roles in immune regulation, the increased understanding of which should reveal therapeutic targets in immunity and immune-mediated disease.


Asunto(s)
Aminoacil-ARNt Sintetasas , Homeostasis , Homeostasis/inmunología , Animales , Humanos , Aminoacil-ARNt Sintetasas/inmunología , Aminoacil-ARNt Sintetasas/metabolismo , Inmunomodulación
3.
Pediatr Neurol ; 156: 178-181, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38788280

RESUMEN

BACKGROUND: Exome sequencing (ES) is a useful tool in diagnosing suspected mitochondrial disease but can miss pathogenic variants for several reasons. Additional testing, such as muscle biopsy or biochemical testing, can be helpful in exome-negative cases. METHODS: We report a patient who presented with repeated episodes of lactic acidosis and failure to thrive. RESULTS: ES and mitochondrial sequencing were initially negative but clinical suspicion for mitochondrial disease remained high. After muscle biopsy showed evidence of mitochondrial dysfunction, the ES was reanalyzed and revealed novel variants in AARS2. CONCLUSION: This case demonstrates the importance of muscle biopsy and biochemical testing in evaluating patients with a high suspicion of mitochondrial disease, even in the genomics era. Closed-loop communication between molecular genetics laboratories and clinical geneticists is an important step to help establish diagnosis in unsolved cases.


Asunto(s)
Enfermedades Mitocondriales , Músculo Esquelético , Fenotipo , Femenino , Humanos , Lactante , Alanina-ARNt Ligasa , Biopsia , Exoma , Secuenciación del Exoma , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/patología , Músculo Esquelético/patología
4.
Front Neurol ; 15: 1376643, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38689878

RESUMEN

Epilepsy, characterized by recurrent seizures, impacts 70-80% of patients, leading to cognitive deficits. The intricate relationship between seizure control and cognitive impairment remains complex. Epileptic encephalopathy (EE), an intensified form often rooted in genetic factors, is detectable through next-generation sequencing, aiding in precise diagnoses, family counseling, and potential treatment strategies. We present a case involving two sisters with refractory generalized seizures evolving into dysarthria, dysphagia, ataxia, and cognitive decline. Despite normal physical exams, abnormal electroencephalogram results consistent with epilepsy were noted. Whole Exome Sequencing identified heterozygous variants in the alanyl-tRNA synthetase (AARS) and Calcium Voltage-Gated Channel Subunit Alpha 1 (CACNA1A) genes. The AARS variant (c.C2083T, p.R695*) was maternal, while the CACNA1A variant (c.G7400C, p.R2467P) was paternal. Patients A and B exhibited a unique blend of neurological and psychiatric conditions, distinct from common disorders that begin adolescence, like Juvenile Myoclonic Epilepsy. Whole Exome Sequencing uncovered an AARS gene and CACNA1A gene, linked to various autosomal dominant phenotypes. Presence in both parents, coupled with familial reports of migraines and seizures, provides insight into accelerated symptom progression. This study underscores the importance of genetic testing in decoding complex phenotypes and emphasizes the value of documenting family history for anticipating related symptoms and future health risks.

5.
Cell ; 187(10): 2375-2392.e33, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38653238

RESUMEN

Lysine lactylation is a post-translational modification that links cellular metabolism to protein function. Here, we find that AARS1 functions as a lactate sensor that mediates global lysine lacylation in tumor cells. AARS1 binds to lactate and catalyzes the formation of lactate-AMP, followed by transfer of lactate to the lysince acceptor residue. Proteomics studies reveal a large number of AARS1 targets, including p53 where lysine 120 and lysine 139 in the DNA binding domain are lactylated. Generation and utilization of p53 variants carrying constitutively lactylated lysine residues revealed that AARS1 lactylation of p53 hinders its liquid-liquid phase separation, DNA binding, and transcriptional activation. AARS1 expression and p53 lacylation correlate with poor prognosis among cancer patients carrying wild type p53. ß-alanine disrupts lactate binding to AARS1, reduces p53 lacylation, and mitigates tumorigenesis in animal models. We propose that AARS1 contributes to tumorigenesis by coupling tumor cell metabolism to proteome alteration.


Asunto(s)
Carcinogénesis , Ácido Láctico , Proteína p53 Supresora de Tumor , Animales , Femenino , Humanos , Ratones , Carcinogénesis/metabolismo , Carcinogénesis/genética , Línea Celular Tumoral , Ácido Láctico/metabolismo , Lisina/metabolismo , Neoplasias/metabolismo , Neoplasias/genética , Procesamiento Proteico-Postraduccional , Proteína p53 Supresora de Tumor/metabolismo , Masculino
6.
J Environ Manage ; 351: 119675, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38048709

RESUMEN

Aerosol Atmospheric Rivers (AARs) are elongated and narrow regions that carry high concentrations of aerosols (tiny particles suspended in the atmosphere) across large distances, exerting effects on both air quality and human health (Chakraborty et al., 2021, 2022). Monitoring and modeling these aerosols present distinct challenges due to their dynamic nature and complex interactions within the atmosphere. In this context, the present study detects and predicts the AARs using MERRA-2 reanalysis datasets with their seasonal climatology of key aerosol species, including Black Carbon (BC), Dust (DU), Organic Carbon (OC), Sea Salt (SS), and Sulphates (SU). The study employs an innovative Integrated Aerosol Transport (IAT) based AAR algorithm from 2015 to 2022. A total count of 44,020 BC AARs, 13,280 DU AARs, 21,599 OC AARs, 17,925 SS AARs, and 31,437 SU AARs were detected globally. The seasonal climatology of BC and OC AARs intensifies in areas such as the Amazon rainforest and Congo during AMJJAS (April-September) due to forest fires. Similarly, DU AARs are more frequent in regions near the Saharan desert, primarily around the equator during AMJJAS. SS AARs tend to predominate over the oceans, while SU AARs are predominantly found in the northern hemisphere, primarily due to higher anthropogenic emissions. Furthermore, convolutional autoencoder-based models were developed for key aerosol species, strengthening predictive accuracy by effectively capturing complex data relationships and delivering precise predictions for the last 5-time frames. During validation, the model evaluation parameters for image prediction such as the Structural Similarity Index ranged from 0.86 to 0.94, Peak Signal-to-Noise Ratio fluctuated between 1.14 and 42.25 dB, Root Mean Square Error varied from 2.39 to 296.4 mg/(m-sec), and Mean Square Error fell within the range of 1.55-17.22 mg/(m-sec). These collectively reflect image closeness, quality, dissimilarity, and accuracy in AAR prediction. This study demonstrates the effectiveness of advanced machine and deep learning models in predicting AARs, offering the potential for advanced forecasting and enhancing resilience in high-aerosol concentration regions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Carbono/análisis , Polvo/análisis , Monitoreo del Ambiente/métodos , Estaciones del Año , Hollín
7.
Cancer Med ; 12(23): 21531-21544, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37990642

RESUMEN

INTRODUCTION: The mitochondrial alanyl-tRNA synthetase 2 (AARS2) as one of aminoacyl-tRNA synthases (ARSs) performs amino acid transportation and involves protein synthesis. However, its role in cancer remains largely unexplored. METHODS: In this study, more than 10,000 samples were enrolled to explore genomic alterations, biological function, prognosis, and clinical treatment based on AARS2 across pan-cancer. The molecular characterization of AARS2 was confirmed in hepatocellular carcinoma (HCC) using proteomics analysis, quantitative real-time PCR, western blotting, immunohistochemical staining, and cell experiments. RESULTS: For genomic landscape, the AARS2 was dramatically upregulated in multiple cancers, which might be mainly caused by copy number alteration rather than mutation and methylation. The abnormal expression of AARS2 was prominently associated with activity of cancer pathways and performed oncogenic roles in most cancers. Systematic experiments in vitro substantiated the elevated expression of AARS2, and the deficiency of it inhibited cell proliferation and cell migration in HCC. Meanwhile, our findings suggested that AARS2 could serve as a novel promising and stable biomarker for assessing prognosis and immunotherapy. Moreover, a variety of therapeutic drugs and targeted pathways were proposed for cancer treatment, which might enhance clinical efficacy. CONCLUSION: The AARS2 could serve as a new oncogenic gene that promotes cell proliferation and migration in HCC. The comprehensive investigations increased the understanding of AARS2 across human cancers and generated beginning insights of AARS2 in genomic landscape, molecular biological function, prognosis, and clinical treatment.


Asunto(s)
Alanina-ARNt Ligasa , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Alanina-ARNt Ligasa/genética , Alanina-ARNt Ligasa/metabolismo , Biomarcadores , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Pronóstico
9.
Front Neurol ; 14: 878446, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37456626

RESUMEN

Objectives: To report the first Mexican case with two novel AARS2 mutations causing primary ovarian failure, uterus infantilis, and early-onset dementia secondary to leukoencephalopathy. Methods: Detailed clinical, clinimetric, neuroimaging features, muscle biopsy with biochemical assays of the main oxidative phosphorylation complexes activities, and molecular studies were performed on samples from a Mexican female. Results: We present a 41-year-old female patient with learning difficulties since childhood and primary amenorrhea who developed severe cognitive, motor, and behavioral impairment in early adulthood. Neuroimaging studies revealed frontal leukoencephalopathy with hypometabolism at the fronto-cerebellar cortex and caudate nucleus. Uterus infantilis was detected on ultrasound study. Clinical exome sequencing identified two novel variants, NM_020745:c.2864G>A (p.W955*) and NM_020745:c.1036C>A (p.P346T, p.P346Wfs*18), in AARS2. Histopathological and biochemical studies on muscle biopsy revealed mitochondrial disorder with cytochrome C oxidase (COX) deficiency. Conclusions: Several adult-onset cases of leukoencephalopathy and ovarian failure associated with AARS2 variants have been reported. To our best knowledge, none of them showed uterus infantilis. Here we enlarge the genetic and phenotypic spectrum of AARS2-related dementia with leukoencephalopathy and ovarian failure and contribute with detailed clinical, clinometric, neuroimaging, and molecular studies to disease and novel molecular variants characterization.

10.
J Biochem ; 174(3): 291-303, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37261968

RESUMEN

Glycyl-tRNA synthetases (GlyRSs) have different oligomeric structures depending on the organisms. While a dimeric α2 GlyRS species is present in archaea, eukaryotes and some eubacteria, a heterotetrameric α2ß2 GlyRS species is found in most eubacteria. Here, we present the crystal structure of heterotetrameric α2ß2 GlyRS, consisting of the full-length α and ß subunits, from Lactobacillus plantarum (LpGlyRS), gram-positive lactic bacteria. The α2ß2LpGlyRS adopts the same X-shaped structure as the recently reported Escherichia coli α2ß2 GlyRS. A tRNA docking model onto LpGlyRS suggests that the α and ß subunits of LpGlyRS together recognize the L-shaped tRNA structure. The α and ß subunits of LpGlyRS together interact with the 3'-end and the acceptor region of tRNAGly, and the C-terminal domain of the ß subunit interacts with the anticodon region of tRNAGly. The biochemical analysis using tRNA variants showed that in addition to the previously defined determinants G1C72 and C2G71 base pairs, C35, C36 and U73 in eubacterial tRNAGly, the identification of bases at positions 4 and 69 in tRNAGly is required for efficient glycylation by LpGlyRS. In this case, the combination of a purine base at Position 4 and a pyrimidine base at Position 69 in tRNAGly is preferred.


Asunto(s)
Glicina-ARNt Ligasa , Lactobacillus plantarum , ARN de Transferencia , Lactobacillus plantarum/metabolismo , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Glicina-ARNt Ligasa/química , Glicina-ARNt Ligasa/metabolismo , Cristalografía por Rayos X
11.
Methods Enzymol ; 679: 275-293, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36682865

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) catalyze aminoacylation of tRNAs to produce aminoacyl-tRNAs for protein synthesis. Bacterial aaRSs have distinctive features, play an essential role in channeling amino acids into biomolecular assembly, and are vulnerable to inhibition by small molecules. The aaRSs continue to be targets for potential antibacterial drug development. The first step of aaRS reaction is the activation of amino acid by hydrolyzing ATP to form an acyladenylate intermediate with the concomitant release of pyrophosphate. None-radioactive assays usually measure the rate of ATP consumption or phosphate generation, offering advantages in high-throughput drug screening. These simple aaRS enzyme assays can be adapted to study the mode of inhibition of natural or synthetic aaRS inhibitors. Taking phenylalanyl-tRNA synthetase (PheRS) of Mycobacterium tuberculosis (Mtb) as an example, we describe a process for identification and characterization of Mtb PheRS inhibitor.


Asunto(s)
Aminoacil-ARNt Sintetasas , Mycobacterium tuberculosis , Fenilalanina-ARNt Ligasa , Mycobacterium tuberculosis/metabolismo , Aminoacil-ARNt Sintetasas/genética , ARN de Transferencia/metabolismo , Aminoácidos , Adenosina Trifosfato
12.
Biochem Biophys Rep ; 33: 101426, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36647555

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) catalyze the ligation of amino acids to cognate tRNAs by consuming one molecule of ATP. Magnesium is essential for the enzymes' activity. Certain class II aaRSs, such as lysyl-tRNA synthetase (LysRS) and seryl-tRNA synthetase (SerRS), recognize ATP together with three magnesium ions in the active site. The detailed role of how these magnesium ions facilitate the ATP recognition by the enzyme is unclear. Here, we report analyses of a crystal structure of human LysRS, in which the two enzymatic pockets of the LysRS dimer are in different states. One pocket is vacant of ATP, and the other is in an intermediate state of ATP recognition. Interestingly, only one magnesium ion instead of three is bound in both states. Compared with our previously solved LysRS structures, we proposed the order of binding for the three magnesium ions. These structures also reveal multiple intermediate ATP-bound states during the amino acid activation reaction, providing critical insights into the mechanisms of the magnesium-dependent enzyme activity of class II aaRSs.

13.
Cerebellum ; 22(1): 59-69, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35084689

RESUMEN

Mutations in the alanyl-transfer RNA synthase 2 (AARS2) represent a heterogenous group of autosomal recessive leukodystrophy characterized by cognitive decline, ataxia, spasticity, and Parkinsonism. AARS2-related leukodystrophy (AARS2-L) is extremely rare. To date, only 45 genetically confirmed cases, explaining the frequent diagnostic delay. Here, we report a 21-year-old male presented with unsteady gait and weakness in the bilateral lower extremities. Examination revealed dysarthria, cerebellar ataxia, paraparesis, and Parkinsonism with generalized hyperreflexia. MRI findings showed extensive white matter lesions in bilateral frontoparietal lobes, immediate periventricular regions, and corpus callosum. Focused exome sequencing revealed compound heterozygous mutations in the AARS2 gene confirming the diagnosis of AARS2-L; two heterogeneous missense mutations (c.452 T > C, p. M151T; c. 2557C > T, p. R853W) appeared together for the first time. We also reviewed phenotypic spectra of AARS2-related leukodystrophies from a total of 45 reported cases.


Asunto(s)
Enfermedades Desmielinizantes , Leucoencefalopatías , Enfermedades Neurodegenerativas , Masculino , Humanos , Adulto Joven , Adulto , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/genética , Diagnóstico Tardío , Mutación , Mutación Missense , Imagen por Resonancia Magnética
14.
J Autoimmun ; 134: 102951, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36470210

RESUMEN

OBJECTIVES: Autoantibodies are thought to play a key role in the pathogenesis of idiopathic inflammatory myopathies (IIM). However, up to 40% of IIM patients, even those with clinical manifestations of anti-synthetase syndrome (ASSD), test seronegative to known myositis-specific autoantibodies. We hypothesized the existence of new potential autoantigens among human cytoplasmic aminoacyl tRNA synthetases (aaRS) in patients with IIM. METHODS: Plasma samples from 217 patients with IIM according to 2017 EULAR/ACR criteria, including 50 patients with ASSD, 165 without, and two with unknown ASSD status were identified retrospectively, as well as age and gender-matched sera from 156 population controls, and 219 disease controls. Patients with previously documented ASSD had to test positive for at least one of the five most common anti-aaRS autoantibodies (anti-Jo1, -PL7, -PL12, -EJ, and -OJ) and present with one or more of the following clinical manifestations: interstitial lung disease, myositis, arthritis, Raynaud's phenomenon, fever, or mechanic's hands. Demographics, laboratory, and clinical data of the IIM cohort (ASSD and non-ASSD) were compared. Samples were screened using a multiplex bead array assay for presence of autoantibodies against a panel of 117 recombinant protein variants, representing 33 myositis-related proteins, including all nineteen cytoplasmic aaRS. Prospectively collected clinical data for the IIM cohort were retrieved and compared between groups within the IIM cohort and correlated with the results of the autoantibody screening. Principal component analysis was used to analyze clinical manifestations between ASSD, non-ASSD groups, and individuals with novel anti-aaRS autoantibodies. RESULTS: We identified reactivity towards 16 aaRS in 72 of the 217 IIM patients. Twelve patients displayed reactivity against nine novel aaRS. The novel autoantibody specificities were detected in four previously seronegative patients for myositis-specific autoantibodies and eight with previously detected myositis-specific autoantibodies. IIM individuals with novel anti-aaRS autoantibodies (n = 12) all had signs of myositis, and they had either muscle weakness and/or muscle enzyme elevation, 2/12 had mechanic's hands, 3/12 had interstitial lung disease, and 2/12 had arthritis. The individuals with novel anti-aaRS and a pathological muscle biopsy all presented widespread up-regulation of major histocompatibility complex class I. The reactivities against novel aaRS could be confirmed in ELISA and western blot. Using the multiplex bead array assay, we could confirm previously known reactivities to four of the most common aaRS (Jo1, PL12, PL7, and EJ (n = 45)) and identified patients positive for anti-Zo, -KS, and -HA (n = 10) that were not previously tested. A low frequency of anti-aaRS autoantibodies was also detected in controls. CONCLUSION: Our results suggest that most, if not all, cytoplasmic aaRS may become autoantigenic. Autoantibodies against new aaRS may be found in plasma of patients previously classified as seronegative with potential high clinical relevance.


Asunto(s)
Aminoacil-ARNt Sintetasas , Artritis , Enfermedades Pulmonares Intersticiales , Miositis , Humanos , Estudios Retrospectivos , Autoantígenos , Autoanticuerpos , Síndrome
15.
Development ; 149(17)2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35929539

RESUMEN

tRNA synthetase deficiency leads to unfolded protein responses in neuronal disorders; however, its function in embryonic neurogenesis remains unclear. This study identified an aars1cq71/cq71 mutant zebrafish allele that showed increased neuronal apoptosis and compromised neurogenesis. aars1 transcripts were highly expressed in primary neural progenitor cells, and their aberration resulted in protein overloading and activated Perk. nfe2l2b, a paralog of mammalian Nfe2l2, which encodes Nrf2, is a pivotal executor of Perk signaling that regulates neuronal phenotypes in aars1cq71/cq71 mutants. Interference of nfe2l2b in nfe2l2bΔ1/Δ1 mutants did not affect global larval development. However, aars1cq71/cq71;nfe2l2bΔ1/Δ1 mutant embryos exhibited increased neuronal cell survival and neurogenesis compared with their aars1cq71/cq71 siblings. nfe2l2b was harnessed by Perk at two levels. Its transcript was regulated by Chop, an implementer of Perk. It was also phosphorylated by Perk. Both pathways synergistically assured the nuclear functions of nfe2l2b to control cell survival by targeting p53. Our study extends the understanding of tRNA synthetase in neurogenesis and implies that Nrf2 is a cue to mitigate neurodegenerative pathogenesis.


Asunto(s)
Alanina-ARNt Ligasa , Factor 2 Relacionado con NF-E2 , Animales , Diferenciación Celular/genética , Supervivencia Celular/genética , Mamíferos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Pez Cebra
16.
Mol Biochem Parasitol ; 251: 111510, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35988745

RESUMEN

TriTryp diseases (Leishmaniasis, Human African Trypanosomiasis (HAT), and Chagas disease) are devastating parasitic neglected tropical diseases (NTDs) that affect billions of people in developing countries, cause high mortality in humans, and impose a large socio-economic burden. The current treatment options against tritryp diseases are suboptimal and challenging due to the emergence of resistance against available tritryp drugs. Hence, designing and developing effective anti-tritryp drugs with novel targets are required. Aminoacyl-tRNA synthetases (AARSs) involved in specific aminoacylation of transfer RNAs (tRNAs), interrupt protein synthesis through inhibitors, and retard the parasite growth. AaRSs have long been studied as therapeutic targets in bacteria, and three aaRS inhibitors, mupirocin (against IleRS), tavaborole AN2690 (against LeuRS), and halofuginone (against ProRS), are already in clinical practice. The structural differences between tritryp and human aaRSs and the presence of unique sequences (N-terminal domain/C-terminal domain/catalytic domain) make them potential target for developing selective inhibitors. Drugs based on a single aaRS target developed by high-throughput screening (HTS) are less effective due to the emergence of resistance. However, designing multi-targeted drugs may be a better strategy for resistance development. In this perspective, we discuss the characteristics of tritryp aaRSs, sequence conservation in their orthologs and their peculiarities, recent advancements towards the single-target and multi-target aaRS inhibitors developed through rational design.


Asunto(s)
Aminoacil-ARNt Sintetasas , Enfermedad de Chagas , Leishmaniasis , Tripanosomiasis Africana , Aminoacil-ARNt Sintetasas/química , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Aminoacilación , Animales , Humanos , Leishmaniasis/tratamiento farmacológico , Enfermedades Desatendidas/tratamiento farmacológico , Tripanosomiasis Africana/tratamiento farmacológico
17.
BMC Neurol ; 22(1): 299, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35971119

RESUMEN

BACKGROUND: Aminoacyl tRNA-synthetases are ubiquitously-expressed enzymes that attach amino acids to their cognate tRNA molecules. Mutations in several genes encoding aminoacyl tRNA-synthetases, have been associated with peripheral neuropathy, i.e. AARS1, GARS1, HARS1, YARS1 and WARS1. The pathogenic mechanism underlying AARS1-related neuropathy is not known. METHODS: From 2012 onward, all probands presenting at Telemark Hospital (Skien, Norway) with peripheral neuropathy were screened for variants in AARS1 using an "in-house" next-generation sequencing panel. DNA from patient's family members was examined by Sanger sequencing. Blood from affected family members and healthy controls were used for quantification of AARS1 mRNA and alanine. Proteomic analyses were conducted in peripheral blood mononuclear cells (PBMC) from four affected family members and five healthy controls. RESULTS: Seventeen individuals in two Norwegian families affected by Charcot-Marie-Tooth disease (CMT) were characterized in this study. The heterozygous NM_001605.2:c.976C > T p.(Arg326Trp) AARS1 mutation was identified in ten affected family members. All living carriers had a mild to severe length-dependent sensorimotor neuropathy. Three deceased obligate carriers aged 74-98 were reported to be unaffected, but were not examined in the clinic. Proteomic studies in PBMC from four affected individuals suggest an effect on the immune system mediated by components of a systemic response to chronic injury and inflammation. Furthermore, altered expression of proteins linked to mitochondrial function/dysfunction was observed. Proteomic data are available via ProteomeXchange using identifier PXD023842. CONCLUSION: This study describes clinical and neurophysiological features linked to the p.(Arg326Trp) variant of AARS1 in CMT-affected members of two Norwegian families. Proteomic analyses based on of PBMC from four CMT-affected individuals suggest that involvement of inflammation and mitochondrial dysfunction might contribute to AARS1 variant-associated peripheral neuropathy.


Asunto(s)
Alanina-ARNt Ligasa , Enfermedad de Charcot-Marie-Tooth , Alanina-ARNt Ligasa/genética , Enfermedad de Charcot-Marie-Tooth/genética , Humanos , Inflamación , Leucocitos Mononucleares/metabolismo , Mutación , Linaje , Proteoma/genética , Proteómica
18.
Artículo en Inglés | MEDLINE | ID: mdl-35975211

RESUMEN

A 55-year-old male presented with apraxia of gait with exaggerated upper limb movement with relative preservation of cognition and mild spasticity of limbs. His investigations reveal posterior-predominant leukodystrophy in brain magnetic resonance imaging (MRI) and compound heterozygous mutations in mitochondrial alanyl-transfer RNA synthetase 2 (AARS2) by next generation sequencing. His asymptomatic brother also has MRI changes with subtle mild pyramidal signs. AARS2 mutation is a rare cause of mitochondrial encephalopathy which may give rise to leukodystrophy with premature ovarian failure, infantile cardiomyopathy, lung hypoplasia and myopathy. Gait apraxia as primary presenting feature of this rare variant of mitochondrial encephalomyopathy is hitherto un-reported.


Asunto(s)
Alanina-ARNt Ligasa , Leucoencefalopatías , Encefalomiopatías Mitocondriales , Alanina-ARNt Ligasa/genética , Apraxia de la Marcha , Humanos , Leucoencefalopatías/complicaciones , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/genética , Masculino , Persona de Mediana Edad , Extremidad Superior
19.
Front Bioeng Biotechnol ; 10: 918659, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35845409

RESUMEN

Cell-free biology is increasingly utilized for engineering biological systems, incorporating novel functionality, and circumventing many of the complications associated with cells. The central dogma describes the information flow in biology consisting of transcription and translation steps to decode genetic information. Aminoacyl tRNA synthetases (AARSs) and tRNAs are key components involved in translation and thus protein synthesis. This review provides information on AARSs and tRNA biochemistry, their role in the translation process, summarizes progress in cell-free engineering of tRNAs and AARSs, and discusses prospects and challenges lying ahead in cell-free engineering.

20.
J Spine Surg ; 8(2): 224-233, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35875625

RESUMEN

Background: Atlantoaxial rotatory subluxation (AARS) is a rare injury of the C1/C2 junction. It is often associated with trauma in adults. Treatment may depend on the duration of symptoms and clinical presentation, but there is no consensus regarding the ideal management of these injuries. Our objective is to ascertain the prevalence of neurological deficit, complications, and outcomes of patients diagnosed with AARS undergoing cervical fusion (CF) versus those treated without CF. Methods: The 2016-2019 National Inpatient Sample (NIS) was queried using International Classification of Diseases, 10th revision (ICD-10) for adult patients with C1/C2 subluxation. Patients undergoing CF were defined through ICD-10 procedure codes. Baseline health and acute illness severity was calculated using the 11-point modified frailty index (mFI-11). Presenting characteristics, treatment complications, and outcomes were evaluated of CF vs. non-CF patients. Results: Of 990 adult patients with AARS, 720 were treated without CF and 270 were treated with CF. CF patients were more often myelopathic. Patients that had undergone CF treatment were negatively associated with having had extensive trauma. Patients undergoing CF experienced significantly longer length of stay (LOS), increased healthcare resource utilization, and decreased inpatient mortality. Sepsis had a negative association with patients that underwent CF treatment while pneumonia had a positive association. Conclusions: Adult patients undergoing CF for AARS demonstrated an increase in healthcare resource utilization but also a significant decrease in mortality. Extent of acute injury appears to have a strong influence on decision making for CF. Further study of decision making for treatment of this rare injury in adults is warranted.

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