OBJECTIVE: To analyze the clinical characteristics and genotypic changes of six children with RARS2 gene variants. METHODS: The clinical data of 6 children with RARS2 gene variants diagnosed at the Third Affiliated Hospital of Zhengzhou University from January 2017 to August 2024 were collected. Genetic variants were detected using trio-whole exome sequencing. Genomic DNA was extracted from samples and subjected to high-throughput sequencing. Variants were detected and analyzed using relevant databases and software. Pathogenic variants were validated by Sanger sequencing. The protein structure encoded by a previously unreported variant was predicted using a SWISS-MODEL online server. This study was approved by the Medical Ethics Committee of the Third Affiliated Hospital of Zhengzhou University (Ethics No.: 2024-373-01). RESULTS: Among the six children, four were males and two were females, with the most recent follow-up age ranging from 1-year-and-1-month to 7 years old. The age of onset was under 1 year in all cases. All six children exhibited seizures, including infantile spasms in three, spasms and tonic spasms in one, and focal seizures in two. One child became seizure-free for 4 ~ 5 years following Valproic acid combined with topiramate and adrenocorticotropic hormone (ACTH) pulse therapy, but subsequently experienced a relapse. Another child has remained seizure-free for nearly one year with oral sodium valproate, levetiracetam, and a "cocktail" therapy. Seizures were not controlled in the remaining four children. Pontocerebellar hypoplasia was observed on neuroimaging in two children. All six patients exhibited severe psychomotor retardation. A total of 10 RARS2 gene variants were identified, three of which were previously unreported. CONCLUSION The predominant clinical features of Pontocerebellar hypoplasia associated with RARS2 gene variants include infantile onset, severe psychomotor retardation or regression, drug-resistant epilepsy, and feeding difficulties. The characteristic neuroimaging finding is pontocerebellar hypoplasia. However, its appearance may vary widely with time. The majority of affected children have a poor prognosis.
Humans ; Male ; Female ; Child, Preschool ; Infant ; Child ; Olivopontocerebellar Atrophies/genetics* ; Arginine-tRNA Ligase/genetics* ; Mutation ; Cerebellar Diseases

OBJECTIVE: To summarize the clinical characteristics of 57 patients diagnosed with anti-glycyl tRNA synthetase (anti-EJ) positive antisynthetase syndrome (ASS), a subtype of anti-glycyl tRNA positive ASS, complicated by interstitial lung disease (ILD), and to investigate the factors asso-ciated with ILD recurrence. METHODS: A retrospective analysis was conducted on the clinical data of 57 anti-EJ positive ASS patientswho were treated at the First Affiliated Hospital of Nanjing Medical University from January 1, 2020 to June 30, 2024. The data collected included demographic information, clinical characteristics, laboratory test results, chest CT findings, and pulmonary function tests. The characteristics of ILD recurrence were also analyzed. RESULTS: All the 57 patients with anti-EJ positive ASS were diagnosed with ILD. The mean age at disease onset was (58.18±10.27) years, with a mean disease duration of 3.00 (2.00, 16.00) months. Among the patients, 70. 18% were female, 87.72% experienced a cough, 70. 18% had expectoration, 89.47% reported respiratory difficulties, and 14.04% developed respiratory failure. The results of pulmonary function test showed that the percentage of forced vital capacity (FVC) in the normal predicted value (FVC%), the percentage of forced expiratory volume in the first second (FEV1) in the normal predicted value (FEV1%) and the percentage of diffusion lung carbon monoxide (DLCO) in the normal predicted value (DLCO%) were 59.36±21.41, 58.34±19.46 and 58.17±27.95, respectively. The oxygenation index was (363.24±99.42) mmHg. Chest CT imaging showed that nonspecific interstitial pneumonia (NSIP) was the most common radiographic pattern. Among the 46 patients who completed a follow-up of more than 12 months, 21 cases (45.65%) showed recurrence of ILD. The average age of onset for the recurrence group was (61.38±8.63) years, while that for the non-recurrence group was (55.28±11.85) years, with a difference approaching statistical significance (P=0.056). Further analysis showed that the ESR (erythrocyte sedimentation rate) level was significantly higher in the recurrence group than in the non-recurrence group [(50.48±29.64) mm/h vs. 30.28±23.97) mm/h, P=0.025], and the IgM (immune globulin M) level was also significantly higher in the recurrence group (P=0.042). Moreover, the CD8+T proportion was significantly higher in the recurrence group than in the non-recurrence group (25.48±11.81 vs. 18.59± 8.53, P=0.027). Despite the fact that the recurrence group had a higher baseline age, higher ESR, IgM, and CD8+T proportion, multivariate binary logistic regression analysis showed that these indicators were not independent risk factors for ILD recurrence. CONCLUSION ILD is the most common clinical manifestation in patients with anti-EJ positive ASS, with a significant impact on pulmonary function. Although the patients responded well to a combination of glucocorticoid and immunosuppressive therapies, the recurrence rate remains high, particularly in those with increased sputum production, and elevated ESR. Close monitoring and early intervention for high-risk patients are essential to improving long-term outcomes.
Humans ; Lung Diseases, Interstitial ; Female ; Male ; Middle Aged ; Retrospective Studies ; Myositis/diagnosis* ; Respiratory Function Tests ; Glycine-tRNA Ligase ; Recurrence ; Aged ; Tomography, X-Ray Computed ; Autoantibodies/blood*

OBJECTIVES: Multiple myeloma (MM) is a plasma cell malignancy occurring in middle and old age. MM is still an incurable disease due to its frequent recurrence and drug resistance. However, its pathogenesis is still unclear. Abnormal amino acid metabolism is one of the important characteristics of MM, and the important metabolic pathway of amino acids participates in protein synthesis as basic raw materials. Aminoacyl transfer ribonucleic acid synthetase (ARS) gene is a key regulatory gene in protein synthesis. This study aims to explore the molecular mechanism for ARS, a key factor of amino acid metabolism, in regulating amino acid metabolism in MM and affecting MM growth. METHODS: The corresponding gene number was combined with the gene expression profile GSE5900 dataset and GSE2658 dataset in Gene Expression Omnibus (GEO) database to standardize the gene expression data of ARS. GSEA_4.2.0 software was used to analyze the difference of gene enrichment between healthy donors (HD) and MM patients in GEO database. GraphPad Prism 7 was used to draw heat maps and perform data analysis. Kaplan-Meier and Cox regression model were used to analyze the expression of ARS gene and the prognosis of MM patients, respectively. Bone marrow samples from 7 newly diagnosed MM patients were collected, CD138⁺ and CD138^- cells were obtained by using CD138 antibody magnetic beads, and the expression of ARS in MM clinical samples was analyzed by real-time RT-PCR. Human B lymphocyte GM12878 cells and human MM cell lines ARP1, NCI-H929, OCI-MY5, U266, RPMI 8266, OPM-2, JJN-3, KMS11, MM1.s cells were selected as the study objects. The expression of ARS in MM cell lines was analyzed by real-time RT-PCR and Western blotting. Short hairpin RNA (shRNA) lentiviruses were used to construct gene knock-out plasmids (VARS-sh group). No-load plasmids (scramble group) and gene knock-out plasmids (VARS-sh group) were transfected into HEK 293T cells with for virus packaging, respectively. Stable expression cell lines were established by infecting ARP1 and OCI-MY5 cells, and the effects of knockout valyl-tRNA synthetase (VARS) gene on proliferation and apoptosis of MM cells were detected by cell counting and flow cytometry, respectively. GEO data were divided into a high expression group and a low expression group according to the expression of VARS. Bioinformatics analysis was performed to explore the downstream pathways affected by VARS. Gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and high performance liquid chromatography (HPLC) were used to detect the valine content in CD138⁺ cells and ARP1, OCI-MY5 cells and supernatant of knockdown VARS gene in bone marrow samples from patients, respectively. RESULTS: Gene enrichment analysis showed that tRNA processing related genes were significantly enriched in MM compared with HD (P<0.0001). Further screening of tRNA processing-pathway related subsets revealed that cytoplasmic aminoacyl tRNA synthetase family genes were significantly enriched in MM (P<0.0001). The results of gene expression heat map showed that the ARS family genes except alanyl-tRNA synthetase (AARS), arginyl-tRNA synthetase (RARS), seryl-tRNA synthetase (SARS) in GEO data were highly expressed in MM (all P<0.01). With the development of monoclonal gammopathy of undetermined significance (MGUS) to MM, the gene expression level was increased gradually. Kaplan-Meier univariate analysis of survival results showed that there were significant differences in the prognosis of MM patients in methionyl-tRNA synthetase (MARS), asparaginyl-tRNA synthetase (NARS) and VARS between the high expression group and the low expression group (all P<0.05). Cox regression model multivariate analysis showed that the high expression of VARS was associated with abnormal overall survival time of MM (HR=1.83, 95% CI 1.10 to 3.06, P=0.021). The high expression of NARS (HR=0.90, 95% CI 0.34 to 2.38) and MARS (HR=1.59, 95% CI 0.73 to 3.50) had no effect on the overall survival time of MM patients (both P>0.05). Real-time RT-PCR and Western blotting showed that VARS, MARS and NARS were highly expressed in CD138⁺ MM cells and MM cell lines of clinical patients (all P<0.05). Cell counting and flow cytometry results showed that the proliferation of MM cells by knockout VARS was significantly inhibited (P<0.01), the proportion of apoptosis was significantly increased (P<0.05). Bioinformatics analysis showed that in addition to several pathways including the cell cycle regulated by VARS, the valine, leucine and isoleucine catabolic pathways were upregulated. Non-targeted metabolomics data showed reduced valine content in CD138⁺ tumor cells in MM patients compared to HD (P<0.05). HPLC results showed that compared with the scramble group, the intracellular and medium supernatant content of ARP1 cells and the medium supernatant of OCI-MY5 in the VARS-shRNA group was increased (all P<0.05). CONCLUSIONS MM patients with abnormal high expression of VARS have a poor prognosis. VARS promotes the malignant growth of MM cells by affecting the regulation of valine metabolism.
Humans ; Valine-tRNA Ligase ; Multiple Myeloma/genetics* ; Metabolomics ; Amino Acids ; RNA, Transfer

OBJECTIVE: To explore the genetic etiology for an infant featuring convulsive status epilepticus, developmental delay and elevated plasma lactate. METHODS: Whole exome sequencing and mitochondrial D-loop sequencing were carried out for the infant. Candidate variants were verified by Sanger sequencing. Previously reported FARS2 gene variants were searched from the PubMed, Wanfang and CNKI databases. RESULTS: The infant was found to harbor compound heterozygous variants of the FARS2 gene, namely c.925G>A (p.G309S) and c.405C>A (p.H135Q), which were inherited from its mother and father, respectively. The former has been recorded by the HGMD as a pathogenic variant, whilst the latter was predicted to be likely pathogenic based on the guidelines of the American College of Medical Genetics and Genomics. A total of 30 COXPD14 cases were retrieved from the literature, with common mutations including missense variants, in-frame deletions, splice-site variants and large deletions. CONCLUSION The common manifestations of COXPD14 have included developmental delay (96%), status epilepticus (97%) and increased lactic acid (96%). The compound heterozygous variants of the FARS2 gene probably underlay the disorder in this child.
Female ; Humans ; Infant ; Genetic Testing ; Mitochondrial Diseases ; Mitochondrial Proteins/genetics* ; Phenylalanine-tRNA Ligase ; Status Epilepticus ; Exome Sequencing

As conserved enzymes with important functions, aminoacyl-tRNA synthetase are expressed ubiquitously in cells. These include cytoplasmic aminoacyl-tRNA synthetase, mitochondrial aminoacyl-tRNA synthetase and bifunctional aminoacyl-tRNA synthetase. Mitochondrial aminoacyl-tRNA synthetases catalyze the binding of amino acids with its corresponding tRNA in the mitochondria and participate in the translation of 13 subunits of oxidative phosphorylation enzyme complexes encoded by the mitochondrial genome. Mutations in genes encoding mitochondrial aminoacyl-tRNA synthase may cause a variety of genetic disorders. This review has summarized the clinical characteristics, molecular pathogenesis and treatment of genetic diseases caused by mutations of such genes.
Humans ; RNA, Transfer, Amino Acyl ; Genes, Mitochondrial ; Amino Acyl-tRNA Synthetases/genetics* ; Genome, Mitochondrial ; Mitochondria/genetics*

Unnatural amino acid orthogonal translation machinery can insert unnatural amino acids at desired sites of protein through stop codon by means of foreign orthogonal translation system composed of aminoacyl-tRNA synthetase and orthogonal tRNA genes. This new genetic engineering technology is not only a new tool for biochemical researches of proteins, but also an epoch-making technology for the development of new-type live viral vaccines. The mutated virus containing premature termination codon in genes necessary for replication can be propagated in transgenic cells harboring unnatural amino acid orthogonal translation machinery in media with corresponding unnatural amino acid, but it cannot replicate in conventional host cells. This replication-deficient virus is a new-type of live viral vaccine that possesses advantages of high efficacy of traditional attenuated vaccine and high safety of killed vaccine. This article reviews the application and prospect of unnatural amino acid orthogonal translation machinery in the development of novel replication-deficient virus vaccines.
Amino Acids ; genetics ; Amino Acyl-tRNA Synthetases ; Genetic Engineering ; Protein Engineering ; RNA, Transfer ; Viral Vaccines

The imbalance of protein metabolism is the major cause of skeletal muscle atrophy, and the decrease of protein synthesis directly leads to the occurrence and development of age-related sarcopenia. The canonical role of leucyl-tRNA synthetase (LeuRS) is ligating leucine to the cognate tRNA, and thus it plays a central role in genetic coding. With the further studies of LeuRS in recent years, LeuRS has been found to control protein homeostasis in aging skeletal muscle via its non-canonical role. In this paper, we reviewed the structure and biological features of aminoacyl-tRNA synthetase and LeuRS, and summarized the recent advances in studies on the effects of LeuRS in regulating aging skeletal muscle protein synthesis as an intracellular leucine sensor. Moreover, we also analyzed the potential role of LeuRS in activation of mammalian target of rapamycin complex 1 (mTORC1) signaling transduction pathway in response to anabolic stimuli such as exercise and amino acids ingestion. This paper may provide some new ideas for the prevention, diagnosis and treatment of age-related sarcopenia.
Amino Acyl-tRNA Synthetases ; genetics ; Leucine-tRNA Ligase ; genetics ; Muscle, Skeletal ; Protein Biosynthesis

OBJECTIVE: To study the clinical features of the diseases associated with aminoacyl-tRNA synthetases (ARS) deficiency. METHODS: A retrospective analysis was performed of the clinical and gene mutation data of 10 children who were diagnosed with ARS gene mutations, based on next-generation sequencing from January 2016 to October 2019. RESULTS: The age of onset ranged from 0 to 9 years among the 10 children. Convulsion was the most common initial symptom (7 children). Clinical manifestations included ataxia and normal or mildly retarded intellectual development (with or without epilepsy; n=4) and onset of epilepsy in childhood with developmental regression later (n=2). Some children experienced disease onset in the neonatal period and had severe epileptic encephalopathy, with myoclonus, generalized tonic-clonic seizure, and convulsive seizure (n=4); 3 had severe delayed development, 2 had feeding difficulty, and 1 had hearing impairment. Mutations were found in five genes: 3 had novel mutations in the AARS2 gene (c.331G>C, c.2682+5G>A, c.2164C>T, and c.761G>A), 2 had known mutations in the DARS2 gene (c.228-16C>A and c.536G>A), 1 had novel mutations in the CARS2 gene (c.1036C>T and c.323T>G), 1 had novel mutations in the RARS2 gene (c.1210A>G and c.622C>T), and 3 had novel mutations in the AARS gene (c.1901T>A, c.229C>T, c.244C>T, c.961G>C, c.2248C>T, and Chr16:70298860-70316687del). CONCLUSIONS A high heterogeneity is observed in the clinical phenotypes of the diseases associated with the ARS deficiency. A total of 14 novel mutations in 5 genes are reported in this study, which enriches the clinical phenotypes and genotypes of the diseases associated with ARS deficiency.
Amino Acyl-tRNA Synthetases ; genetics ; Child ; Epilepsy ; Humans ; Mutation ; Phenotype ; Retrospective Studies

PURPOSE: Identification of lymph node (LN) metastasis in non-small cell lung cancer (NSCLC) is critical for disease staging and selection of therapeutic modalities. Sometimes it is not possible to obtain LN core tissue by endobronchial ultrasound-guided transbronchial needle aspirate (EBUS-TBNA), resulting in low diagnostic yield. MATERIALS AND METHODS: In this study, 138 specimens were collected from 108 patients who underwent EBUS-TBNA under the suspicion of LN metastasis of NSCLC. Diagnostic yields of anti-CD45 and anti-methionyl-tRNA synthetase (MRS), immunofluorescent (IF) staining on cytology specimens were compared with those of conventional cytology and positron emission tomography-computed tomography (PET-CT). RESULTS: MRS was strongly expressed in NSCLC cells metastasized to LNs, but weakly expressed in cells at the periphery of the LN germinal center. The majority of cells were CD20 positive, although a few cells were either CD3 or CD14 positive, indicating that CD45 staining is required for discrimination of non-malignant LN constituent cells from NSCLC cells. When the diagnostic efficacy of MRS/CD45 IF staining was evaluated using 138 LN cellular aspirates from 108 patients through EBUS-TBNA, the sensitivity was 76.7% and specificity was 90.8%, whereas those of conventional cytology test were 71.8% and 100.0%, respectively. Combining the results of conventional cytology testing and those of PET-CT showed a sensitivity and specificity of 71.6% and 100%, and the addition of MRS/CD45 dual IF data to this combination increased sensitivity and specificity to 85.1% and 97.8%, respectively. CONCLUSION: MRS/CD45 dual IF staining showed good diagnostic performance and may be a good tool complementing conventional cytology test for determining LN metastasis of NSCLC.
Amino Acyl-tRNA Synthetases ; Carcinoma, Non-Small-Cell Lung ; Complement System Proteins ; Discrimination (Psychology) ; Electrons ; Germinal Center ; Humans ; Ligases ; Lymph Nodes ; Methionine-tRNA Ligase ; Needles ; Neoplasm Metastasis ; Sensitivity and Specificity

No abstract available.
Alanine-tRNA Ligase* ; Dementia* ; Leukoencephalopathies*