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1.
Emerg Infect Dis ; 29(4): 792-796, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36918378

RESUMEN

Since April 2022, waves of SARS-CoV-2 Omicron variant cases have surfaced in Taiwan and spread throughout the island. Using high-throughput sequencing of the SARS-CoV-2 genome, we analyzed 2,405 PCR-positive swab samples from 2,339 persons and identified the Omicron BA.2.3.7 variant as a major lineage within recent community outbreaks in Taiwan.


Asunto(s)
COVID-19 , Humanos , Taiwán/epidemiología , COVID-19/epidemiología , SARS-CoV-2/genética , Brotes de Enfermedades
2.
Clin Immunol ; 247: 109236, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36669607

RESUMEN

Activated zeta-chain-associated protein kinase 70 (ZAP70) phosphorylates the TCRαß:CD3:zeta complex to diversify and amplify TCR signaling. Patients with ZAP70 mutations can present with phenotypes of immune dysregulation as well as infection. We identified the first Taiwanese boy with the [Asp521Asn] ZAP70 mutation who presented with recurrent pneumonia, inflammatory bowel disease-like diarrhea, transient hematuria and autoimmune hepatitis. He had isolated CD8 lymphopenia, eosinophilia, hypogammaglobulinemia, and impaired lymphocyte proliferation. Downstream CD3/CD28 signaling, phosphorylation of AKT, ZAP70 and Ca2+ influx were decreased in [Asp521Asn] ZAP70 lymphocytes. Immunophenotyping analysis revealed expansion of transitional B and CD21-low B cells, Th2-skewing T follicular helper cells, but lower Treg cells. The Asp521Asn-ZAP70 hindered TCR-CD3 downstream phosphorylation and disturbed lymphocyte subgroup "profiles" leading to autoimmunity/autoinflammation. Further large-scale studies are warranted to clarify this lymphocyte disturbance. The prognosis significantly depends on hematopoietic stem cell transplantation, but not the genotype, the presence of opportunistic infections or immune dysregulation.


Asunto(s)
Receptores de Antígenos de Linfocitos T alfa-beta , Transducción de Señal , Masculino , Animales , Proteína Tirosina Quinasa ZAP-70/genética , Mutación , Fosforilación , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Linfocitos T Reguladores/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo
3.
Int J Mol Sci ; 23(16)2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-36012532

RESUMEN

Anthracycline-induced cardiomyopathy has been noted as a non-neglectable issue in the field of clinical oncology. Remarkable progress has been achieved in searching for inherited susceptible genetic deficits underlying anthracycline cardiotoxicity in the past several years. In this case report, we present the preliminary results of a genetic study in a young male patient who was treated with standard dose anthracycline-based chemotherapy for his acute myeloid leukemia and attacked by acute congestive heart failure after just two courses of therapy. After a survey of 76 target genes, an in-frame deletion of the titin gene was recognized as the most possible genetic defect responsible for his cardiomyopathy caused by anthracycline. This defect proved to pass down from the patient's mother and did not exist in seven unrelated chemotherapy-treated cancer patients without chemotherapy-induced cardiomyopathy and four other healthy volunteer DNA donors.


Asunto(s)
Antraciclinas , Cardiomiopatías , Antraciclinas/efectos adversos , Antibióticos Antineoplásicos/efectos adversos , Cardiomiopatías/inducido químicamente , Cardiomiopatías/complicaciones , Cardiomiopatías/genética , Cardiotoxicidad/etiología , Causalidad , Conectina/genética , Humanos , Masculino
4.
J Biomed Sci ; 28(1): 65, 2021 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-34565360

RESUMEN

BACKGROUND: Heterozygous pathogenic variants in STUB1 are implicated in autosomal dominant spinocerebellar ataxia type 48 (SCA48), which is a rare familial ataxia disorder. We investigated the clinical, genetic and functional characteristics of STUB1 mutations identified from a Taiwanese ataxia cohort. METHODS: We performed whole genome sequencing in a genetically undiagnosed family with an autosomal dominant ataxia syndrome. Further Sanger sequencing of all exons and intron-exon boundary junctions of STUB1 in 249 unrelated patients with cerebellar ataxia was performed. The pathogenicity of the identified novel STUB1 variant was investigated. RESULTS: We identified a novel heterozygous frameshift variant, c.832del (p.Glu278fs), in STUB1 in two patients from the same family. This rare mutation is located in the U-box of the carboxyl terminus of the Hsc70-interacting protein (CHIP) protein, which is encoded by STUB1. Further in vitro experiments demonstrated that this novel heterozygous STUB1 frameshift variant impairs the CHIP protein's activity and its interaction with the E2 ubiquitin ligase, UbE2D1, leading to neuronal accumulation of tau and α-synuclein, caspase-3 activation, and promoting cellular apoptosis through a dominant-negative pathogenic effect. The in vivo study revealed the influence of the CHIP expression level on the differentiation and migration of cerebellar granule neuron progenitors during cerebellar development. CONCLUSIONS: Our findings provide clinical, genetic, and a mechanistic insight linking the novel heterozygous STUB1 frameshift mutation at the highly conserved U-box domain of CHIP as the cause of autosomal dominant SCA48. Our results further stress the importance of CHIP activity in neuronal protein homeostasis and cerebellar functions.


Asunto(s)
Mutación del Sistema de Lectura , Ataxias Espinocerebelosas/genética , Ubiquitina-Proteína Ligasas/genética , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Taiwán , Ubiquitina-Proteína Ligasas/metabolismo
5.
PLoS Genet ; 12(5): e1006051, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27203079

RESUMEN

In an effort to identify the functional alleles associated with hepatocellular carcinoma (HCC), we investigated 152 genes found in the 4q21-25 region that exhibited loss of heterozygosity (LOH). A total of 2,293 pairs of primers were designed for 1,449 exonic and upstream promoter regions to amplify and sequence 76.8-114 Mb on human chromosome 4. Based on the results from analyzing 12 HCC patients and 12 healthy human controls, we discovered 1,574 sequence variations. Among the 99 variants associated with HCC (p < 0.05), four are from the Dickkopf 2 (DKK2) gene: three in the promoter region (g.-967A>T, g.-923C>A, and g.-441T>G) and one in the 5'UTR (c.550T>C). To verify the results, we expanded the subject cohort to 47 HCC cases and 88 healthy controls for conducting haplotype analysis. Eight haplotypes were detected in the non-tumor liver tissue samples, but one major haplotype (TAGC) was found in the tumor tissue samples. Using a reporter assay, this HCC-associated allele registered the lowest level of promoter activity among all the tested haplotype sequences. Retention of this allele in LOH was associated with reduced DKK2 transcription in the HCC tumor tissues. In HuH-7 cells, DKK2 functioned in the Wnt/ß-catenin signaling pathway, as an antagonist of Wnt3a, in a dose-dependent manner that inhibited Wnt3a-induced cell proliferation. Taken together, the genotyping and functional findings are consistent with the hypothesis that DKK2 is a tumor suppressor; by selectively retaining a transcriptionally inactive DKK2 allele, the reduction of DKK2 function results in unchecked Wnt/ß-catenin signaling, contributing to HCC oncogenesis. Thus our study reveals a new mechanism through which a tumor suppressor gene in a LOH region loses its function by allelic selection.


Asunto(s)
Carcinoma Hepatocelular/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Neoplasias Hepáticas/genética , Pérdida de Heterocigocidad/genética , Alelos , Carcinoma Hepatocelular/patología , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Femenino , Genes Supresores de Tumor , Genotipo , Haplotipos , Humanos , Neoplasias Hepáticas/patología , Masculino , Vía de Señalización Wnt , beta Catenina/genética
6.
J Biol Chem ; 292(22): 9305-9319, 2017 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-28381553

RESUMEN

GTPases of immunity-associated proteins (GIMAPs) are expressed in lymphocytes and regulate survival/death signaling and cell development within the immune system. We found that human GIMAP6 is expressed primarily in T cell lines. By sorting human peripheral blood mononuclear cells and performing quantitative RT-PCR, GIMAP6 was found to be expressed in CD3+ cells. In Jurkat cells that had been knocked down for GIMAP6, treatment with hydrogen peroxide, FasL, or okadaic acid significantly increased cell death/apoptosis. Exogenous expression of GMAP6 protected Huh-7 cells from apoptosis, suggesting that GIMAP6 is an anti-apoptotic protein. Furthermore, knockdown of GIMAP6 not only rendered Jurkat cells sensitive to apoptosis but also accelerated T cell activation under phorbol 12-myristate 13-acetate/ionomycin treatment conditions. Using this experimental system, we also observed a down-regulation of p65 phosphorylation (Ser-536) in GIMAP6 knockdown cells, indicating that GIMAP6 might display anti-apoptotic function through NF-κB activation. The conclusion from the study on cultured T cells was corroborated by the analysis of primary CD3+ T cells, showing that specific knockdown of GIMAP6 led to enhancement of phorbol 12-myristate 13-acetate/ionomycin-mediated activation signals. To characterize the biochemical properties of GIMAP6, we purified the recombinant GIMAP6 to homogeneity and revealed that GIMAP6 had ATPase as well as GTPase activity. We further demonstrated that the hydrolysis activity of GIMAP6 was not essential for its anti-apoptotic function in Huh-7 cells. Combining the expression data, biochemical properties, and cellular features, we conclude that GIMAP6 plays a role in modulating immune function and that it does this by controlling cell death and the activation of T cells.


Asunto(s)
Adenosina Trifosfatasas/inmunología , Proteínas Reguladoras de la Apoptosis/inmunología , GTP Fosfohidrolasas/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Adenosina Trifosfatasas/genética , Proteínas Reguladoras de la Apoptosis/genética , GTP Fosfohidrolasas/genética , Humanos , Ionomicina/farmacología , Células Jurkat , Fosforilación/efectos de los fármacos , Fosforilación/inmunología , Acetato de Tetradecanoilforbol/farmacología , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/inmunología
7.
Mol Cell Proteomics ; 15(1): 12-25, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26499836

RESUMEN

Nosocomial infectious outbreaks caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious threat to human health. Phosphoproteomics of pathogenic bacteria has been used to identify the mechanisms of bacterial virulence and antimicrobial resistance. In this study, we used a shotgun strategy combined with high-accuracy mass spectrometry to analyze the phosphoproteomics of the imipenem-susceptible strain SK17-S and -resistant strain SK17-R. We identified 410 phosphosites on 248 unique phosphoproteins in SK17-S and 285 phosphosites on 211 unique phosphoproteins in SK17-R. The distributions of the Ser/Thr/Tyr/Asp/His phosphosites in SK17-S and SK17-R were 47.0%/27.6%/12.4%/8.0%/4.9% versus 41.4%/29.5%/17.5%/6.7%/4.9%, respectively. The Ser-90 phosphosite, located on the catalytic motif S(88)VS(90)K of the AmpC ß-lactamase, was first identified in SK17-S. Based on site-directed mutagenesis, the nonphosphorylatable mutant S90A was found to be more resistant to imipenem, whereas the phosphorylation-simulated mutant S90D was sensitive to imipenem. Additionally, the S90A mutant protein exhibited higher ß-lactamase activity and conferred greater bacterial protection against imipenem in SK17-S compared with the wild-type. In sum, our results revealed that in A. baumannii, Ser-90 phosphorylation of AmpC negatively regulates both ß-lactamase activity and the ability to counteract the antibiotic effects of imipenem. These findings highlight the impact of phosphorylation-mediated regulation in antibiotic-resistant bacteria on future drug design and new therapies.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Imipenem/farmacología , Proteoma/metabolismo , Proteómica/métodos , beta-Lactamasas/metabolismo , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Sitios de Unión/genética , Infección Hospitalaria/microbiología , Humanos , Modelos Moleculares , Mutación , Fosfoproteínas/metabolismo , Fosforilación , Estructura Terciaria de Proteína , Espectrometría de Masas en Tándem , Resistencia betalactámica/efectos de los fármacos , beta-Lactamasas/química , beta-Lactamasas/genética
8.
Mol Cell ; 36(1): 131-40, 2009 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-19818716

RESUMEN

IkappaB kinase beta (IKKbeta) is involved in tumor development and progression through activation of the nuclear factor (NF)-kappaB pathway. However, the molecular mechanism that regulates IKKbeta degradation remains largely unknown. Here, we show that a Cullin 3 (CUL3)-based ubiquitin ligase, Kelch-like ECH-associated protein 1 (KEAP1), is responsible for IKKbeta ubiquitination. Depletion of KEAP1 led to the accumulation and stabilization of IKKbeta and to upregulation of NF-kappaB-derived tumor angiogenic factors. A systematic analysis of the CUL3, KEAP1, and RBX1 genomic loci revealed a high percentage of genome loss and missense mutations in human cancers that failed to facilitate IKKbeta degradation. Our results suggest that the dysregulation of KEAP1-mediated IKKbeta ubiquitination may contribute to tumorigenesis.


Asunto(s)
Quinasa I-kappa B/metabolismo , Péptidos y Proteínas de Señalización Intracelular/fisiología , FN-kappa B/metabolismo , Transducción de Señal/fisiología , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular , Línea Celular Tumoral , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Variaciones en el Número de Copia de ADN/genética , Femenino , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Humanos , Quinasa I-kappa B/genética , Interleucina-8/genética , Estimación de Kaplan-Meier , Proteína 1 Asociada A ECH Tipo Kelch , Ratones , Mutación/fisiología , Neoplasias/genética , Neoplasias/metabolismo , Neovascularización Fisiológica/genética , Unión Proteica/fisiología , Dominios y Motivos de Interacción de Proteínas/fisiología , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo , Transfección , Factor de Necrosis Tumoral alfa/farmacología , Ubiquitinación/fisiología
9.
Genes Dev ; 23(10): 1183-94, 2009 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-19451219

RESUMEN

CISD2, the causative gene for Wolfram syndrome 2 (WFS2), is a previously uncharacterized novel gene. Significantly, the CISD2 gene is located on human chromosome 4q, where a genetic component for longevity maps. Here we show for the first time that CISD2 is involved in mammalian life-span control. Cisd2 deficiency in mice causes mitochondrial breakdown and dysfunction accompanied by autophagic cell death, and these events precede the two earliest manifestations of nerve and muscle degeneration; together, they lead to a panel of phenotypic features suggestive of premature aging. Our study also reveals that Cisd2 is primarily localized in the mitochondria and that mitochondrial degeneration appears to have a direct phenotypic consequence that triggers the accelerated aging process in Cisd2 knockout mice; furthermore, mitochondrial degeneration exacerbates with age, and the autophagy increases in parallel to the development of the premature aging phenotype. Additionally, our Cisd2 knockout mouse work provides strong evidence supporting an earlier clinical hypothesis that WFS is in part a mitochondria-mediated disorder; specifically, we propose that mutation of CISD2 causes the mitochondria-mediated disorder WFS2 in humans. Thus, this mutant mouse provides an animal model for mechanistic investigation of Cisd2 protein function and help with a pathophysiological understanding of WFS2.


Asunto(s)
Envejecimiento Prematuro/fisiopatología , Envejecimiento/genética , Envejecimiento/metabolismo , Proteínas Portadoras/metabolismo , Mitocondrias/metabolismo , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/metabolismo , Envejecimiento Prematuro/genética , Animales , Autofagia , Proteínas Relacionadas con la Autofagia , Modelos Animales de Enfermedad , Femenino , Intolerancia a la Glucosa/genética , Intolerancia a la Glucosa/fisiopatología , Humanos , Longevidad/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Músculos/patología , Neuronas/patología , Enfermedades del Nervio Óptico/genética , Enfermedades del Nervio Óptico/fisiopatología , Síndrome de Wolfram/fisiopatología
10.
Biochim Biophys Acta ; 1852(7): 1540-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25912735

RESUMEN

Epidermal growth factor receptor (EGFR) gene mutations are strongly associated with lung adenocarcinoma and favorable response to EGFR tyrosine kinase inhibitor. The mutated EGFR proteins (EGFRs) are hyper-phosphorylated and refractory to receptor down-regulation. To address the discrepancy between hyper-phosphorylation and lack of down-regulation of mutant EGFRs, we have examined the expression of EGFR negative regulators in non-small cell lung cancer (NSCLC) cell lines. We found that NSCLC cell lines expressing mutant EGFRs often had low expression of various negative regulators for EGFR. Among them, tumor suppressor CD82 was up-regulated by wild type (WT) EGFR but down-regulated by mutant EGFRs. Reconstitution of CD82 exerted stronger suppressive effects on mutant EGFRs than on WT EGFR. Active exportation of CD82 through the exosome was one of the mechanisms involved in achieving the overall CD82 down-regulation in mutant EGFR-expressing lung cancer cell lines. Over-expression of mutant EGFR protein frequently occurred in the lung cancer tissues of mutant EGFR-transgenic mice and also associated with CD82 down-regulation. Immunoblot analyses on the tumor tissues from 23 lung adenocarcinoma patients (12 with WT EGFR, and 11 with mutant EGFRs) also identified significantly stronger down-regulation of CD82 in tumors with mutant EGFRs than WT. Our data indicate that CD82 down-regulation could be a critical step involved in the EGFR over-expression and the stronger tumorigenic activity triggered by EGFR mutations. Up-regulation of the CD82 level may become a promising new treatment strategy for lung adenocarcinoma.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Receptores ErbB/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteína Kangai-1/metabolismo , Neoplasias Pulmonares/metabolismo , Mutación , Adenocarcinoma/genética , Adenocarcinoma del Pulmón , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Receptores ErbB/genética , Humanos , Proteína Kangai-1/genética , Neoplasias Pulmonares/genética , Ratones
11.
J Antimicrob Chemother ; 70(10): 2734-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26180132

RESUMEN

OBJECTIVES: To investigate the link between two NDM-1-positive Acinetobacter isolates from the same hospital, the plasmid profiles of the isolates were examined. These two isolates were found from a surveillance programme within 3 months from two patients without obvious physical contact or hospitalization time overlap. METHODS: Antimicrobial susceptibility tests, genome sequencing of both isolates and plasmid transfer experiments were performed. A comparative study of similar plasmids was performed using BLAST analysis. RESULTS: The antimicrobial susceptibility of the isolates (Acinetobacter soli M131 and Acinetobacter pittii MS32) and their Escherichia coli transconjugants revealed a conjugative plasmid that carried the carbapenem resistance determinant. Eleven plasmids were observed in M131 and three in MS32. Each isolate shared an identical plasmid that carried the blaNDM-1 gene. This 47 271 bp plasmid harbours a conserved blaNDM-1-containing region that is flanked by ISAba125 and ISAba11 elements, and also contains a Ti-type conjugative operon. The plasmid is nearly identical in sequence to those of Acinetobacter isolates from China. In contrast to the mobilization of the blaNDM-1 sequence in Enterobacteriaceae, which is mainly by transposition, this plasmid moves as a whole among Acinetobacter species. Consistently, this plasmid was found to transfer effectively by in vitro conjugation to several Acinetobacter species. CONCLUSIONS: The clinical and laboratory findings suggest that Acinetobacter species may serve as a reservoir of this blaNDM-1 plasmid. Our study demonstrates the potential of applying genome sequencing to the surveillance of antimicrobial-resistant bacteria.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter/genética , Conjugación Genética , Transferencia de Gen Horizontal , Plásmidos/genética , beta-Lactamasas/genética , Acinetobacter/efectos de los fármacos , Antibacterianos/farmacología , Infección Hospitalaria , Elementos Transponibles de ADN , Orden Génico , Genoma Bacteriano , Humanos , Pruebas de Sensibilidad Microbiana , Resistencia betalactámica
12.
Ann Surg Oncol ; 22 Suppl 3: S1419-27, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25472652

RESUMEN

BACKGROUND: DNA methylation is a potential tumor marker for several cancers, including colorectal cancer (CRC), because of its heritable and stable characteristics. METHODS: Using a high-resolution, genome-wide approach, we epigenotyped >450,000 CpG sites in tumor and adjacent non-tumor tissues from 23 microsatellite instability (MSI)/microsatellite stability (MSS) CRC cases. Using matrix-assisted laser desorption ionization-time of flight mass spectrometry, the methylation status of five frequently hypermethylated genes were confirmed in 75 independent CRC series and 353 CRC patients with available plasma. RESULTS: Compared with non-tumor tissues, 13 MSI tumors had 34,836 (7 %) aberrant methylation sites, 87 % of which were hypermethylated. In contrast, only 9,806 (2 %) differentially methylated sites were identified in ten MSS cases (62 % hypermethylated). In both MSI and MSS, 228 promoter-associated CpG islands were hypermethylated, with AGBL4, ZNF625, MDFI, TWIST1, and FLI1 being most frequently hypermethylated. In an independent set of 35 MSI and 40 MSS cases, the methylation status of these five genes significantly differed between tumor and adjacent non-tumor tissues. Of 353 CRC patients, 230 (65.2 %), 232 (65.7 %), and 247 (70.0 %) had AGBL4, FLI1, and TWIST1 promoter hypermethylation in circulating cell-free DNA, respectively. In patients without metastasis, the sensitivity of any two or three hypermethylation markers was 52.8-57.8 and 27.9-38.9 %, respectively. The sensitivity of any two or three markers was significantly high in patients with stage IV disease (73.0 and 55.6 %, respectively). The prognostic value of these epimarkers was inconclusive. CONCLUSION: DNA methylation patterns differed in CRC subtypes. The identified hypermethylation markers in CRC patients may have good sensitivity in different CRC stages.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Inestabilidad de Microsatélites , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/patología , Islas de CpG , Femenino , Estudios de Seguimiento , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Regiones Promotoras Genéticas/genética , Tasa de Supervivencia
13.
PLoS Genet ; 8(8): e1002867, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22912590

RESUMEN

Genome-wide transcription start site (TSS) profiles of the enterobacteria Escherichia coli and Klebsiella pneumoniae were experimentally determined through modified 5' RACE followed by deep sequencing of intact primary mRNA. This identified 3,746 and 3,143 TSSs for E. coli and K. pneumoniae, respectively. Experimentally determined TSSs were then used to define promoter regions and 5' UTRs upstream of coding genes. Comparative analysis of these regulatory elements revealed the use of multiple TSSs, identical sequence motifs of promoter and Shine-Dalgarno sequence, reflecting conserved gene expression apparatuses between the two species. In both species, over 70% of primary transcripts were expressed from operons having orthologous genes during exponential growth. However, expressed orthologous genes in E. coli and K. pneumoniae showed a strikingly different organization of upstream regulatory regions with only 20% identical promoters with TSSs in both species. Over 40% of promoters had TSSs identified in only one species, despite conserved promoter sequences existing in the other species. 662 conserved promoters having TSSs in both species resulted in the same number of comparable 5' UTR pairs, and that regulatory element was found to be the most variant region in sequence among promoter, 5' UTR, and ORF. In K. pneumoniae, 48 sRNAs were predicted and 36 of them were expressed during exponential growth. Among them, 34 orthologous sRNAs between two species were analyzed in depth, and the analysis showed that many sRNAs of K. pneumoniae, including pleiotropic sRNAs such as rprA, arcZ, and sgrS, may work in the same way as in E. coli. These results reveal a new dimension of comparative genomics such that a comparison of two genomes needs to be comprehensive over all levels of genome organization.


Asunto(s)
Escherichia coli/genética , Genoma Bacteriano , Klebsiella pneumoniae/genética , Regiones Promotoras Genéticas , Sitio de Iniciación de la Transcripción , Regiones no Traducidas 5' , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Perfilación de la Expresión Génica , Genómica , Datos de Secuencia Molecular , Operón/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Transcripción Genética
14.
Hum Mol Genet ; 21(18): 3956-68, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22661501

RESUMEN

The CISD2 gene, which is an evolutionarily conserved novel gene, encodes a transmembrane protein primarily associated with the mitochondrial outer membrane. Significantly, the CISD2 gene is located within the candidate region on chromosome 4q where a genetic component for human longevity has been mapped. Previously, we have shown that Cisd2 deficiency shortens lifespan resulting in premature aging in mice. Additionally, an age-dependent decrease in Cisd2 expression has been detected during normal aging. In this study, we demonstrate that a persistent level of Cisd2 achieved by transgenic expression in mice extends their median and maximum lifespan without any apparent deleterious side effects. Cisd2 also ameliorates age-associated degeneration of the skin, skeletal muscles and neurons. Moreover, Cisd2 protects mitochondria from age-associated damage and functional decline as well as attenuating the age-associated reduction in whole-body energy metabolism. These results suggest that Cisd2 is a fundamentally important regulator of lifespan and provide an experimental basis for exploring the candidacy of CISD2 in human longevity.


Asunto(s)
Proteínas Portadoras/genética , Longevidad/genética , Proteínas del Tejido Nervioso/genética , Animales , Proteínas Relacionadas con la Autofagia , Proteínas Portadoras/metabolismo , Transporte de Electrón/genética , Metabolismo Energético , Femenino , Expresión Génica , Glutatión/metabolismo , Humanos , Esperanza de Vida , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/enzimología , Mitocondrias/metabolismo , Músculos/patología , Músculos/fisiopatología , Vaina de Mielina/patología , NADH Deshidrogenasa/metabolismo , Degeneración Nerviosa/genética , Degeneración Nerviosa/fisiopatología , Proteínas del Tejido Nervioso/metabolismo , Consumo de Oxígeno , Sarcopenia/genética , Sarcopenia/patología , Sarcopenia/fisiopatología , Envejecimiento de la Piel/genética
15.
Mol Genet Metab ; 111(4): 507-12, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24613481

RESUMEN

BACKGROUND: In view of the therapeutic benefits resulting from early intervention for Fabry disease, our team has implemented an enzyme-based newborn screening in Taiwan since 2008. However, we found that most heterozygous females cannot be detected. To improve the screening efficiency, a more effective method for GLA gene genotyping is necessary. METHODS: As the suspected mutations are limited to only 29 different spots in Taiwanese, a panel of Sequenom iPLEX assay was designed for rapid screening of GLA variations. To determine the accuracy and sensitivity of this assay, previously diagnosed and undiagnosed DNA samples were analyzed by this genotyping assay and Sanger sequencing. In addition, DNA extracted from dried blood spots was also tested. RESULTS: Sequenom iPLEX assay is accurate and cost-effective, identifying the sequence variations, which were designated in the panel. It identified common GLA variants in DNA samples extracted from whole blood or dried blood spots with 100% accuracy and sensitivity. CONCLUSIONS: Sequenom iPLEX assay is suitable for Fabry newborn screening when hotspot mutations and common variations are known in a well-studied population. In addition, this assay can also be applied for first-line determination of GLA variant sequences in suspected subjects of high-risk patients, or newborns.


Asunto(s)
ADN/genética , Enfermedad de Fabry/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Espectrometría de Masas/métodos , Mutación/genética , Secuencia de Bases , Enfermedad de Fabry/diagnóstico , Femenino , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Taiwán
16.
J Formos Med Assoc ; 113(11): 803-12, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24168833

RESUMEN

BACKGROUND/PURPOSE: Genomic studies have revealed that there is a significant association between a point mutation of the human Col2A1 gene (G1170S) and several hip disorders. The purpose of the study was to explore the phenotype and altered cartilage matrix homeostasis of transgenic mice carrying this mutated Col2a1 gene. METHODS: Wild-type and transgenic mice were used as the control and study groups, respectively. Body weight measurement, radiographic analysis, and histological analysis of the mice were carried out to describe differences between the wild-type and transgenic mice at different ages. Cartilage metabolism studies were also carried out, including an MTT assay of cellular proliferation and nitric oxide and glycosaminoglycan assays. Allelic expression levels of the mutant A allele and the normal G allele were established by TaqMan assay. Cytokine and protease gene expression were measured. RESULTS: Transgenic mice had a lower mean body weight, a deformed skeletal structure, and abnormal cartilage histomorphology. Chondrocyte proliferation was significantly compromised and this was linked to significantly higher NO secretion and less soluble glycosaminoglycan formation. TNF-α and IL-1ß gene expression was significantly upregulated, while MMP-13 gene expression was significantly downregulated. CONCLUSION: The mutant G1170S Col2a1 gene in mice clearly alters the transgenic murine phenotype and cartilage matrix homeostasis.


Asunto(s)
Cartílago/patología , Colágeno Tipo II/genética , Alelos , Animales , Células Cultivadas , Condrocitos/citología , Citocinas/metabolismo , Expresión Génica , Homeostasis , Masculino , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , Ratones Transgénicos , Mutación , Óxido Nítrico/metabolismo , Fenotipo
17.
JAMA ; 312(5): 525-34, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-25096692

RESUMEN

IMPORTANCE: The antiepileptic drug phenytoin can cause cutaneous adverse reactions, ranging from maculopapular exanthema to severe cutaneous adverse reactions, which include drug reactions with eosinophilia and systemic symptoms, Stevens-Johnson syndrome, and toxic epidermal necrolysis. The pharmacogenomic basis of phenytoin-related severe cutaneous adverse reactions remains unknown. OBJECTIVE: To investigate the genetic factors associated with phenytoin-related severe cutaneous adverse reactions. DESIGN, SETTING, AND PARTICIPANTS: Case-control study conducted in 2002-2014 among 105 cases with phenytoin-related severe cutaneous adverse reactions (n=61 Stevens-Johnson syndrome/toxic epidermal necrolysis and n=44 drug reactions with eosinophilia and systemic symptoms), 78 cases with maculopapular exanthema, 130 phenytoin-tolerant control participants, and 3655 population controls from Taiwan, Japan, and Malaysia. A genome-wide association study (GWAS), direct sequencing of the associated loci, and replication analysis were conducted using the samples from Taiwan. The initial GWAS included samples of 60 cases with phenytoin-related severe cutaneous adverse reactions and 412 population controls from Taiwan. The results were validated in (1) 30 cases with severe cutaneous adverse reactions and 130 phenytoin-tolerant controls from Taiwan, (2) 9 patients with Stevens-Johnson syndrome/toxic epidermal necrolysis and 2869 population controls from Japan, and (3) 6 cases and 374 population controls from Malaysia. MAIN OUTCOMES AND MEASURES: Specific genetic factors associated with phenytoin-related severe cutaneous adverse reactions. RESULTS: The GWAS discovered a cluster of 16 single-nucleotide polymorphisms in CYP2C genes at 10q23.33 that reached genome-wide significance. Direct sequencing of CYP2C identified missense variant rs1057910 (CYP2C9*3) that showed significant association with phenytoin-related severe cutaneous adverse reactions (odds ratio, 12; 95% CI, 6.6-20; P=1.1 × 10(-17)). The statistically significant association between CYP2C9*3 and phenytoin-related severe cutaneous adverse reactions was observed in additional samples from Taiwan, Japan, and Malaysia. A meta-analysis using the data from the 3 populations showed an overall odds ratio of 11 (95% CI, 6.2-18; z=8.58; P < .00001) for CYP2C9*3 association with phenytoin-related severe cutaneous adverse reactions. Delayed clearance of plasma phenytoin was detected in patients with severe cutaneous adverse reactions, especially CYP2C9*3 carriers, providing a functional link of the associated variants to the disease. CONCLUSIONS AND RELEVANCE: This study identified CYP2C variants, including CYP2C9*3, known to reduce drug clearance, as important genetic factors associated with phenytoin-related severe cutaneous adverse reactions.


Asunto(s)
Anticonvulsivantes/efectos adversos , Hidrocarburo de Aril Hidroxilasas/genética , Eosinofilia/inducido químicamente , Fenitoína/efectos adversos , Síndrome de Stevens-Johnson/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/farmacocinética , Estudios de Casos y Controles , Citocromo P-450 CYP2C9 , Eosinofilia/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Japón , Malasia , Masculino , Persona de Mediana Edad , Farmacogenética , Fenitoína/farmacocinética , Polimorfismo de Nucleótido Simple , Taiwán , Adulto Joven
18.
PLoS One ; 19(2): e0299196, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422012

RESUMEN

This paper empirically examines the signaling role of feedback in the repeated public goods game. To eliminate the potential impact of feedback's informative function, we test whether the provision of detailed yet redundant feedback leads to increased contributions. Our findings demonstrate that redundant information significantly promotes contributions. Given the equal informative power in both treatments, the observed increase in contributions can be attributed to the signaling effect. Furthermore, an examination of cooperative disposition heterogeneity reveals that conditional cooperators primarily utilize feedback for its informative function, while free riders primarily exploit it for its signaling function. These results offer empirical evidence of the signaling function of feedback and offer valuable insights into the design of feedback provision in repeated public goods settings.


Asunto(s)
Laboratorios , Transducción de Señal , Retroalimentación
19.
Liver Cancer ; 13(1): 41-55, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38344447

RESUMEN

Introduction: A set of genetic mutations to classify hepatocellular carcinoma (HCC) useful to clinical studies is an unmet need. Hepatitis B virus-related HCC (HBV-HCC) harbors a unique genetic mutation, namely, the HBV integration, among other somatic endogenous gene mutations. We explored a combination of HBV DNA integrations and common somatic mutations to classify HBV-HCC by using a capture-sequencing platform. Methods: A total of 153 HBV-HCCs after surgical resection were subjected to capture sequencing to identify HBV integrations and three common somatic mutations in genomes. Three mutually exclusive mutations, HBV DNA integration into the TERT promoter, HBV DNA integration into MLL4, or TERT promoter point mutation, were identified in HBV-HCC. Results: They were used to classify HBV-HCCs into four groups: G1 with HBV-TERT integration (25.5%); G2 with HBV-MLL4 integration (10.5%); G3 with TERT promoter mutation (30.1%); and G4 without these three mutations (34.0%). Clinically, G3 has the highest male-to-female ratio, cirrhosis rate, and associated with higher early recurrence and mortality after resection, but G4 has the best outcome. Transcriptomic analysis revealed a grouping different from the published ones and G2 with an active immune profile related to immune checkpoint inhibitor response. Analysis of integrated HBV DNA provided clues for HBV genotype and variants in carcinogenesis of different HCC subgroup. This new classification was also validated in another independent cohort. Conclusion: A simple and robust genetic classification was developed to aid in understanding HBV-HCC and in harmonizing clinical studies.

20.
J Proteome Res ; 12(1): 33-44, 2013 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-23256888

RESUMEN

Chromosome 4 is the fourth largest chromosome, containing approximately 191 megabases (~6.4% of the human genome) with 757 protein-coding genes. A number of marker genes for many diseases have been found in this chromosome, including genetic diseases (e.g., hepatocellular carcinoma) and biomedical research (cardiac system, aging, metabolic disorders, immune system, cancer and stem cell) related genes (e.g., oncogenes, growth factors). As a pilot study for the chromosome 4-centric human proteome project (Chr 4-HPP), we present here a systematic analysis of the disease association, protein isoforms, coding single nucleotide polymorphisms of these 757 protein-coding genes and their experimental evidence at the protein level. We also describe how the findings from the chromosome 4 project might be used to drive the biomarker discovery and validation study in disease-oriented projects, using the examples of secretomic and membrane proteomic approaches in cancer research. By integrating with cancer cell secretomes and several other existing databases in the public domain, we identified 141 chromosome 4-encoded proteins as cancer cell-secretable/shedable proteins. Additionally, we also identified 54 chromosome 4-encoded proteins that have been classified as cancer-associated proteins with successful selected or multiple reaction monitoring (SRM/MRM) assays developed. From literature annotation and topology analysis, 271 proteins were recognized as membrane proteins while 27.9% of the 757 proteins do not have any experimental evidence at the protein-level. In summary, the analysis revealed that the chromosome 4 is a rich resource for cancer-associated proteins for biomarker verification projects and for drug target discovery projects.


Asunto(s)
Cromosomas Humanos Par 4 , Enfermedad , Proteínas , Cromosomas Humanos Par 4/clasificación , Cromosomas Humanos Par 4/genética , Biología Computacional , Bases de Datos de Proteínas , Enfermedad/clasificación , Enfermedad/genética , Genoma Humano , Proyecto Genoma Humano , Humanos , Proyectos Piloto , Proteínas/clasificación , Proteínas/genética , Proteínas/metabolismo , Proteómica
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