Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 150
Filtrar
1.
Commun Biol ; 5(1): 587, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35705698

RESUMEN

Accurate and high-speed scanning and subsequent selection of the correct start codon are important events in protein synthesis. Eukaryotic mRNAs have long 5' UTRs that are inspected for the presence of a start codon by the ribosomal 48S pre-initiation complex (PIC). However, the conformational state of the 48S PIC required for inspecting every codon is not clearly understood. Here, atomistic molecular dynamics (MD) simulations and energy calculations suggest that the scanning conformation of 48S PIC may reject all but 4 (GUG, CUG, UUG and ACG) of the 63 non-AUG codons, and initiation factor eIF1 is crucial for this discrimination. We provide insights into the possible role of initiation factors eIF1, eIF1A, eIF2α and eIF2ß in scanning. Overall, the study highlights how the scanning conformation of ribosomal 48S PIC acts as a coarse selectivity checkpoint for start codon selection and scans long 5' UTRs in eukaryotic mRNAs with accuracy and high speed.


Asunto(s)
Factor 1 Eucariótico de Iniciación , Iniciación de la Cadena Peptídica Traduccional , Regiones no Traducidas 5' , Codón Iniciador/genética , Factor 1 Eucariótico de Iniciación/genética , Factor 1 Eucariótico de Iniciación/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
2.
Theriogenology ; 180: 87-93, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34954662

RESUMEN

Long noncoding RNAs (lncRNAs) are abundant in mammalian genomes and have been found to play important roles in many biological events. However, the mechanism by which lncRNAs regulate embryonic development remains to be fully elucidated. Here, we investigated the function of the lncRNA, TCONS_00135926 (referred to as lnc5926), through knockdown and overexpression experiments in goat early embryos. Lnc5926 expression at the eight-cell embryonic stage was significantly higher than that at other stages, which was consistent with the pattern of embryonic genome activation (EGA) gene expression. The blastocyst rate after lnc5926 knockdown in eight-cell embryos was significantly lower than that in the control group (0.2% vs. 17.1%, p < 0.05), whereas the cleavage rate was not affected (71.9% vs. 75.1%, p ˃ 0.05). After knockdown or overexpression of lnc5926 in embryos, we measured expression levels of the potential target genes, STAM, HACD1, UBL5, MIOX, ELF1, and the key EGA genes, ZSCAN4 and EIF1AX. Only ZSCAN4 and EIF1AX were significantly downregulated after lnc5926 knockdown, and this effect was reversed by lnc5926 overexpression. We conclude that lnc5926 plays an essential role in early embryonic development in goats by regulating expression of EGA-associated genes.


Asunto(s)
Proteínas de Unión al ADN/genética , Desarrollo Embrionario , Factor 1 Eucariótico de Iniciación/genética , Cabras , ARN Largo no Codificante , Factores de Transcripción/genética , Animales , Blastocisto , Desarrollo Embrionario/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Genoma , Cabras/embriología , Cabras/genética , Embarazo , ARN Largo no Codificante/genética
3.
Microbiologyopen ; 10(6): e1229, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34964294

RESUMEN

The filamentous fungus Magnaporthe oryzae has the potential to be developed as an alternative platform organism for the heterologous production of industrially important enzymes. M. oryzae is easy to handle, fast-growing and unlike yeast, posttranslational modifications like N-glycosylations are similar to the human organism. Here, we established M. oryzae as a host for the expression of the unspecific peroxygenase from the basidiomycete Agrocybe aegerita (AaeUPO). Note, UPOs are attractive biocatalysts for selective oxyfunctionalization of non-activated carbon-hydrogen bonds. To improve and simplify the isolation of AaeUPO in M. oryzae, we fused a Magnaporthe signal peptide for protein secretion and set it under control of the strong EF1α-promoter. The success of the heterologous production of full-length AaeUPO in M. oryzae and the secretion of the functional enzyme was confirmed by a peroxygenase-specific enzyme assay. These results offer the possibility to establish the filamentous ascomycete M. oryzae as a broad applicable alternative expression system.


Asunto(s)
Agrocybe/enzimología , Magnaporthe/genética , Oxigenasas de Función Mixta/biosíntesis , Agrocybe/genética , Factor 1 Eucariótico de Iniciación/genética , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/genética , Magnaporthe/metabolismo , Oxigenasas de Función Mixta/genética , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína/genética , Proteínas Recombinantes/biosíntesis
4.
J Mol Histol ; 52(5): 965-973, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34405343

RESUMEN

Preimplantation embryo development is characterized by drastic nuclear reprogramming and dynamic stage-specific gene expression. Key regulators of this earliest developmental stage have not been revealed. In the present study, a "non-classical" nuclear-localization pattern of eIF1A was observed during early developmental stages of mouse preimplantation embryo before late-morula. In particular, eIF1A is most highly expressed in the nuclear of 2-cell embryo. Knockdown eIF1A by siRNA microinjection affected the development of mouse preimplantation embryo, resulted in decreased blastocyst formation rate. CDX2 protein expression level significantly down-regulated after eIF1A knockdown in morula stage. In addition, the mRNA expression level of Hsp70.1 was also decreased in 2-cell embryo. The results indicate an indispensable role of eIF1A in mouse preimplantation embryos.


Asunto(s)
Núcleo Celular/metabolismo , Desarrollo Embrionario , Factor 1 Eucariótico de Iniciación/metabolismo , Animales , Biomarcadores/metabolismo , Factor 1 Eucariótico de Iniciación/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Genoma , Masculino , Ratones , Factores de Transcripción/metabolismo , Cigoto/metabolismo
5.
Ophthalmic Genet ; 42(6): 732-743, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34353217

RESUMEN

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults, and its metastases are known to be fatal. It is critical to identify molecular markers to be used in potential prognostic evaluation for early diagnosis, treatment, and metastasis or to investigate all aspects of known genetic anomalies. Therefore, this study aimed to analyze the eight genes (GNAQ, GNA11, BAP1, SF3B1, SRSF2, EIF1AX, PLCB4, and CYSLTR2) that are associated with the most common genetic anomalies in UM from a molecular perspective. The genome sequences and expression profiles of 108 UM patients were obtained via bioinformatics tools that provide data from TCGA. The overall mutational load and the mutation patterns for eight genes, in particular, were thoroughly determined. Moreover, PolyPhen2 and SNAP2 tools were used to estimate the oncogenic/pathogenic properties of identified mutations for UM. In addition to the mutation profile, the effects of the presence of a mutation on gene expression and survival were determined. Finally, STRING network analysis was performed to better understand the functional relationships of mutated proteins in cellular processes. There were 27 missense mutations, 16 frameshift mutations, six nonsense mutations, and three splice region mutations among the 52 mutations found in eight genes, and 26 of them had pathogenic properties. BAP1 m-RNA expression was significantly lower in tumors with the mutant genotype (p = .001). The impact of gene expression, which has poor prognostic importance, on survival is statistically significant for high-expressed BAP1 (p = .0015) and low-expressed CYSLTR2 (p = .0021). To assess the current state of this potentially devastating disease, a molecular perspective has been evaluated. Defining this molecular perspective can be useful in developing targeted drug therapies and personalized medicine.


Asunto(s)
Proteínas del Ojo/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Melanoma/genética , Mutación/genética , Proteínas de Neoplasias/genética , Neoplasias de la Úvea/genética , Adulto , Anciano , Anciano de 80 o más Años , Biología Computacional , Análisis Mutacional de ADN , Factor 1 Eucariótico de Iniciación/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Humanos , Masculino , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Fosfolipasa C beta/genética , Fosfoproteínas/genética , Factores de Empalme de ARN/genética , ARN Mensajero/genética , Receptores de Leucotrienos/genética , Factores de Empalme Serina-Arginina/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Neoplasias de la Úvea/mortalidad , Neoplasias de la Úvea/patología , Adulto Joven
6.
Acta Med Acad ; 50(1): 4-12, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34075760

RESUMEN

OBJECTIVE: Mutations in the EIF1AX gene have been recently detected in a small percentage of benign and malignant thyroid lesions. We sought to investigate the prevalence and clinical significance of EIF1AX mutations and co-mutations in cytologically indeterminate thyroid nodules at our institution. MATERIALS AND METHODS: A 5-year retrospective analysis was performed on thyroid nodules with a cytologic diagnosis of Bethesda category III or IV, which had undergone testing by our in-house next generation sequencing panel. Surgically resected nodules with EIF1AX mutations were identified, and mutation type and presence of co-mutations were correlated with histopathologic diagnosis. RESULTS: 41/904 (4.5%) cases overall and 26/229 (11.4%) surgically resected nodules harbored an EIF1AX mutation. The most common histologic diagnoses were follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma. 11/26 (42.3%) of nodules had isolated EIF1AX mutation. Comutations were found in RAS (12/26; 46.2%), TERT (5/26; 19.2%) and TP53 (2/26; 7.7%). EIF1AX mutation alone conferred a 36.4% risk of malignancy (ROM) and 54.5% ROM or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), while the ROM was significantly higher in nodules with concurrent RAS (71.4%), TERT, TP53 and RAS+TERT (100%) mutations. CONCLUSION: EIF1AX mutations occur in benign and malignant follicular thyroid neoplasms. In our cohort, the majority of mutations occurred at the splice acceptor site between exons 5 and 6. Importantly, the coexistence of EIF1AX mutations with other driver pathogenic mutations in RAS, TERT and TP53 conferred a 100% ROM or NIFTP, indicating that such nodules require surgical removal.


Asunto(s)
Adenocarcinoma Folicular , Factor 1 Eucariótico de Iniciación , Neoplasias de la Tiroides , Nódulo Tiroideo , Factor 1 Eucariótico de Iniciación/genética , Humanos , Mutación , Estudios Retrospectivos , Neoplasias de la Tiroides/genética , Nódulo Tiroideo/genética
7.
Mol Biol Rep ; 48(2): 1677-1685, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33575959

RESUMEN

Quantitative gene expression analysis by qPCR requires reference genes for normalization. Lagerstroemia indica (crape myrtle) is a popular ornamental plant in the world, but suitable endogenous reference genes are lacking. To find suitable reference genes, we evaluated the stabilities of nine candidate genes in six experimental data sets: six different tissues, three leaf colors, nine flower colors, and under three abiotic stresses (salt, drought, cold) using four statistical algorithms. A target gene LiMYB56 (homolog of Arabidopsis MYB56) was used to verify the authenticity and accuracy of the candidate reference genes. The results showed that the combination of two stably expressed reference genes, rather than a single reference gene, improved the accuracy of the qPCR. LiEF1α-2 + LiEF1α-3 was best for the tissue, salt treatment, and drought treatment sets; LiEF1α-2 + LiEF1α-1 was optimal for leaf color; LiEF1α-2 + LiACT7 was optimal for cold treatment; and LiUBC + LiEF1α-1 was best for the flower color set. Notably, LiEF1α-2 had high expression stability in all six experimental sets, implying it may be a good reference gene for expression studies in L. indica. Our results will facilitate future gene expression studies in L. indica.


Asunto(s)
Flores/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Lagerstroemia/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estrés Fisiológico/genética , Algoritmos , Proteínas de Arabidopsis/genética , Respuesta al Choque por Frío/genética , Sequías , Factor 1 Eucariótico de Iniciación/genética , Flores/genética , Perfilación de la Expresión Génica , Genes de Plantas , Lagerstroemia/genética , Especificidad de Órganos/genética , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Estrés Salino/genética , Sensibilidad y Especificidad , Cloruro de Sodio/farmacología , Factores de Transcripción/genética
8.
Cell Prolif ; 53(10): e12903, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32926483

RESUMEN

OBJECTIVE: Dysregulation of the cell cycle is associated with the progression of malignant cancer, but its precise functional contribution is unknown. MATERIALS AND METHODS: The expression of EIF1AX in breast cancer tissues was detected by qRT-PCR and immunohistochemistry staining. Colony formation and tumour xenograft assays were used to examine the tumorigenesis-associated function of EIF1AX in vitro and in vivo. RNA-Seq analysis was used to select the downstream target genes of EIF1AX. Flow cytometry, ChIP and luciferase assays were used to investigate the molecular mechanisms by which EIF1AX regulates p21 in breast cancer cells. RESULTS: EIF1AX promoted breast cancer cell proliferation by promoting the G1/S cell cycle transition. A mechanistic investigation showed that EIF1AX inhibited the expression of p21, which is an essential cell cycle regulator. We identified that the transcriptional regulation of p21 by EIF1AX was p53-independent. Clinically, EIF1AX levels were significantly elevated in breast cancer tissues, and the high level of EIF1AX was associated with lower survival rates in breast cancer patients. CONCLUSIONS: Our results imply that EIF1AX may play a key role in the incidence and promotion of breast cancer and may, thus, serve as a valuable target for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama/patología , Proliferación Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Factor 1 Eucariótico de Iniciación/metabolismo , Animales , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Factor 1 Eucariótico de Iniciación/antagonistas & inhibidores , Factor 1 Eucariótico de Iniciación/genética , Femenino , Fase G1 , Humanos , Ratones , Ratones Desnudos , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Fase S , Activación Transcripcional , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Bull Exp Biol Med ; 169(5): 669-672, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32990852

RESUMEN

The feasibility of using molecular genetic markers associated with thyroid neoplasms and more aggressive course of the disease is now actively studied. We analyzed the diagnostic value of somatic mutations in the hot spots of BRAF, KRAS, KRAS, EIF1AX, and TERT genes in histological material from 153 patients with thyroid gland neoplasms. BRAF mutations (exon 15, codon area 600-601) were found in 54 patients, NRAS mutations (exon 3, codon 61) were detected in 12 patients; mutations KRAS, TERT, and EIF1AX genes were not detected.


Asunto(s)
Codón/genética , Factor 1 Eucariótico de Iniciación/genética , Exones/genética , GTP Fosfohidrolasas/genética , Proteínas de la Membrana/genética , Mutación/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Telomerasa/genética , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Humanos , Proteínas Proto-Oncogénicas B-raf/genética
10.
Gene ; 758: 144958, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-32683073

RESUMEN

Short-lived therapeutic gene expression in mammalian cells by DNA methylation is one of the major challenges in gene therapy. In this study, we assessed the implication of DNA methylation on the duration of GFP expression in mouse embryonic stem (ES) and mouse induced pluripotent stem (iPS) cells. The cells were transduced with lentivirus (LV) carrying green fluorescent protein (GFP) driven by either human elongation factor (EF1α) or cytomegalovirus (CMV) promoter. Transduced iPS cells exhibited higher percentage of GFP+ cells with persistent mean fluorescent intensity than transduced ES cells. Analysis on the integrated copy of transgene in the population of the transduced cells demonstrated similar copy number. However, significant increase in GFP intensity following 5-azaC treatment was observed in transduced ES cells only, suggesting the influence of DNA methylation in transgene silencing. Subsequent DNA methylation analysis showed that the promoter and the GFP region of the provirus in iPS cells had negligible methylation profile compared to transduced ES cells. Interestingly, sustained transgene expression was observed upon directed differentiation of transduced iPS cells towards CD34+ CD45+ cells. Hence, this study has shown that favourable transgene activity from lentiviral transduced iPS cells was due to the lack of methylation at the proviral regions.


Asunto(s)
Metilación de ADN/genética , Células Madre Embrionarias/metabolismo , Proteínas Fluorescentes Verdes/genética , Células Madre Pluripotentes Inducidas/metabolismo , Animales , Azacitidina/farmacología , Línea Celular , Citomegalovirus/genética , Factor 1 Eucariótico de Iniciación/genética , Regulación de la Expresión Génica/genética , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Regiones Promotoras Genéticas/genética , Transducción Genética
11.
J Virol Methods ; 284: 113923, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32615131

RESUMEN

Ovine pulmonary adenocarcinoma (OPA) is a globally occurring tumor of lung epithelium which seriously affects the development of sheep farming. In our research, lung tissues of 3 naturally infected OPA individuals and 3 healthy individuals (2-4 years old) were collected. RNA was extracted for transcriptome analysis and reference gene selection. According to transcriptome analysis, 7 candidate reference genes (eukaryotic translation initiation factor 1, EIF1; glyceraldehyde-3-phosphate dehydrogenase, GAPDH; beta-actin, ACTB; GABA Type A receptor-associated protein, GABARAP; activating transcription factor 4, ATF4; ribosomal protein S15, RPS15; and Y-Box binding protein 1, YBX1) showed fragments per kilobase of transcript per million fragments mapped (FPKM) values > 200.0 and standard errors of the means (SEM) < 20.0. Expression of the above candidate reference genes was evaluated by Real-time quantitative polymerase chain reaction (RT-qPCR) combined with the analysis using GeNorm, NormFinder, and BestKeeper software. Comprehensive analysis of the results showed that ACTB was the most stable one, followed by EIF1 and GABARAP. Then, expression stability of the above three genes were validated, suggesting as suitable reference genes in sheep lung tissue, in additional 30 OPA-affected lung tissues and 10 healthy ovine lung tissues. Finally, our findings will be helpful for the subsequent study on the tumorigenic mechanism of OPA.


Asunto(s)
Perfilación de la Expresión Génica/normas , Pulmón/metabolismo , Adenomatosis Pulmonar Ovina/metabolismo , Actinas/genética , Animales , Factor 1 Eucariótico de Iniciación/genética , Femenino , Perfilación de la Expresión Génica/métodos , Retrovirus Ovino Jaagsiekte , Pulmón/patología , Proteínas Asociadas a Microtúbulos/genética , Adenomatosis Pulmonar Ovina/genética , Adenomatosis Pulmonar Ovina/patología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estándares de Referencia , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Ovinos
12.
Cell Rep ; 31(1): 107497, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32268096

RESUMEN

In higher eukaryotes, the mRNA sequence in the direct vicinity of the start codon, called the Kozak sequence (CRCCaugG, where R is a purine), is known to influence the rate of the initiation process. However, the molecular basis underlying its role remains poorly understood. Here, we present the cryoelectron microscopy (cryo-EM) structures of mammalian late-stage 48S initiation complexes (LS48S ICs) in the presence of two different native mRNA sequences, ß-globin and histone 4, at overall resolution of 3 and 3.5 Å, respectively. Our high-resolution structures unravel key interactions from the mRNA to eukaryotic initiation factors (eIFs): 1A, 2, 3, 18S rRNA, and several 40S ribosomal proteins. In addition, we are able to study the structural role of ABCE1 in the formation of native 48S ICs. Our results reveal a comprehensive map of ribosome/eIF-mRNA and ribosome/eIF-tRNA interactions and suggest the impact of mRNA sequence on the structure of the LS48S IC.


Asunto(s)
Factores Eucarióticos de Iniciación/metabolismo , Factores Eucarióticos de Iniciación/ultraestructura , Iniciación de la Transcripción Genética/fisiología , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Codón Iniciador/genética , Codón Iniciador/ultraestructura , Microscopía por Crioelectrón/métodos , Elementos de Facilitación Genéticos/genética , Factor 1 Eucariótico de Iniciación/genética , Factor 1 Eucariótico de Iniciación/metabolismo , Factor 2 Eucariótico de Iniciación/genética , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 3 de Iniciación Eucariótica/genética , Factor 3 de Iniciación Eucariótica/metabolismo , Humanos , Ratones , Iniciación de la Cadena Peptídica Traduccional , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/metabolismo , ARN de Transferencia/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo , Globinas beta/genética , Globinas beta/ultraestructura
13.
Arch Endocrinol Metab ; 64(2): 185-189, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32236306

RESUMEN

The EIF1AX gene mutations have been recently associated with papillary thyroid carcinoma and anaplastic thyroid cancer. According with these reports, the gene as been considered as a drive gene for thyroid cancer development. However, the occurrence of these alterations in benign thyroid lesions is not known and is still under investigation. Some authors have already reported the presence of EIF1AX variants in follicular adenomas and hyperplastic nodules. Here, we describe for the first time a case of a man with the EIF1AX c.338-2A>T splice site mutation in an indeterminate FNA lesion with trabecular adenoma at final histology in the absence of other pathogenetic mutations, demonstrating that further studies are required to better understand EIF1AX role in the tumorigenesis of thyroid carcinoma.


Asunto(s)
Adenoma/diagnóstico , Adenoma/genética , Factor 1 Eucariótico de Iniciación/genética , Mutación/genética , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Biopsia con Aguja Fina , Humanos , Masculino , Persona de Mediana Edad
14.
Arch. endocrinol. metab. (Online) ; 64(2): 185-189, Mar.-Apr. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1131063

RESUMEN

SUMMARY The EIF1AX gene mutations have been recently associated with papillary thyroid carcinoma and anaplastic thyroid cancer. According with these reports, the gene as been considered as a drive gene for thyroid cancer development. However, the occurrence of these alterations in benign thyroid lesions is not known and is still under investigation. Some authors have already reported the presence of EIF1AX variants in follicular adenomas and hyperplastic nodules. Here, we describe for the first time a case of a man with the EIF1AX c.338-2A>T splice site mutation in an indeterminate FNA lesion with trabecular adenoma at final histology in the absence of other pathogenetic mutations, demonstrating that further studies are required to better understand EIF1AX role in the tumorigenesis of thyroid carcinoma.


Asunto(s)
Humanos , Masculino , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Adenoma/diagnóstico , Adenoma/genética , Factor 1 Eucariótico de Iniciación/genética , Mutación/genética , Biopsia con Aguja Fina , Persona de Mediana Edad
15.
J Photochem Photobiol B ; 202: 111720, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31841988

RESUMEN

It has been widely reported that ultraviolet-B (UV-B) radiation is the main extrinsic etiological agent that causes skin photodamage. UV-B exposure mediated photodamage (photo-aging/photo-carcinogenesis) to human skin is caused due to several physiological events at tissue, cellular and molecular levels that lead to impairment of skin function and integrity. In the present study, we investigated the protective role of Trigonelline (TG) against UV-B induced photo-damage in Human Dermal Fibroblasts (Hs68 cells) and Balb/C mice. We exposed human skin fibroblasts and Balb/C mice to UV-B radiation and evaluated various parameters of cellular damage, including, oxidative stress, cytosolic calcium (Ca2+) levels, apoptotic and ER-stress marker proteins. We found that UV-B irradiation induced ROS generation lead to the depletion of endoplasmic reticulum (ER) calcium and increased the expression of ER stress protein markers (phosphorylated elf2α, CHOP, ATF4) as well as apoptotic protein markers (Bcl2, Bax and caspase-9) in a dose and time dependent manner in Hs68 cells. We then determined the effect of TG treatment on UV-B -induced cell death in Hs68 cells and observed that cells exposed to UV-B radiation and treated with TG had a significantly higher survival rate compared to cells exposed to UV-B radiation alone. TG treatment successfully reduced oxidative stress; restored Ca2+ homeostasis and re-established the ER function and prevented apoptotic cell death process. Our results suggest that TG can be used as a potential therapeutic/cosmeceutic agent in preventing skin photo-damage.


Asunto(s)
Alcaloides/farmacología , Apoptosis/efectos de los fármacos , Calcio/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Rayos Ultravioleta , Animales , Apoptosis/efectos de la radiación , Caspasa 9/genética , Caspasa 9/metabolismo , Línea Celular , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/efectos de la radiación , Factor 1 Eucariótico de Iniciación/genética , Factor 1 Eucariótico de Iniciación/metabolismo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Expresión Génica/efectos de los fármacos , Expresión Génica/efectos de la radiación , Humanos , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/metabolismo
16.
Ophthalmic Res ; 63(3): 358-368, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31614358

RESUMEN

BACKGROUND: The purpose of this study is to determine the mutation frequencies of key driver genes in uveal melanoma (UM) in Chinese patients and to detect associations between metastasis and the mutation of these genes. METHOD: A total of 85 patients with UM were enrolled in this study, including 18 patients with metastasis and 67 without metastasis. Sanger sequencing covering the mutational hotspot regions of the G protein subunit alpha Q (GNAQ), GNA11, splicing factor 3B subunit 1 (SF3B1), X-linked eukaryotic translation initiation factor 1A (EIF1AX), phospholipase C beta 4 (PLCB4) and cysteinyl leukotriene receptor 2 (CYSLTR2) genes was used to analyse the mutations in Chinese patients. RESULTS: The frequencies of GNAQ and GNA11 mutations in UM were 45% (38/85) and 35% (30/85) respectively. The frequencies of SF3B1 and EIF1AX mutations were 37% (31/85) and 9% (8/85) respectively. Only 2 mutations were detected in exon 4 of GNAQ, and no mutations were detected in exon 4 of GNA11. A novel mutation, c.627G>T (Q209H) in GNA11 was found. The detected mutations affecting SF3B1 were c.1873C>T (R625C), c.1874G>A (R625H) and c.1874G>T (R625L). The association between the mutations in SF3B1 and low risk of metastasis was statistically significant (OR 0.17, 95% CI 0.035-0.819). The mutations affecting EIF1AX were -23G>A (5'-UTR), c.5C>G (P2R), c.23G>A (G8Q), c.25G>C (G9A) and c.38_39GC>CT (R13P). No mutations were found in the PLCB4 and CYSLTR2 genes. Unfortunately, information on BRCA1-associated protein 1 could not be obtained. CONCLUSIONS: These data indicate that mutations in the PLCB4 and CYSLTR2 genes are rare in Chinese UM patients. The mutations in GNAQ, GNA11 and EIF1AX were not associated with metastasis, whereas SF3B1 mutations were correlated with low risk of metastasis and demonstrated a protective effect in UM patients in China.


Asunto(s)
Factor 1 Eucariótico de Iniciación/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Melanoma/genética , Mutación , Fosfolipasa C beta/genética , Fosfoproteínas/genética , Factores de Empalme de ARN/genética , Receptores de Leucotrienos/genética , Neoplasias de la Úvea/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Análisis Mutacional de ADN , ADN de Neoplasias/genética , Factor 1 Eucariótico de Iniciación/metabolismo , Neoplasias del Ojo/diagnóstico , Neoplasias del Ojo/genética , Neoplasias del Ojo/metabolismo , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/metabolismo , Persona de Mediana Edad , Fosfolipasa C beta/metabolismo , Fosfoproteínas/metabolismo , Factores de Empalme de ARN/metabolismo , Receptores de Leucotrienos/metabolismo , Estudios Retrospectivos , Neoplasias de la Úvea/diagnóstico , Neoplasias de la Úvea/metabolismo , Adulto Joven
17.
Microb Pathog ; 137: 103783, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31600536

RESUMEN

The laboratorial diagnosis of leishmaniasis is based on parasitological methods, which are invasive, present high cost, require laboratorial infrastructure and/or trained professionals; as well as by immunological methods, which usually present variable sensitivity and/or specificity, such as when they are applied to identify asymptomatic cases and/or mammalian hosts presenting low levels of antileishmanial antibodies. As consequence, new studies aiming to identify more refined antigens to diagnose visceral (VL) and tegumentary (TL) leishmaniasis are urgently necessary. In the present work, the Leishmania eukaryotic elongation factor-1 beta (EF1b) protein, which was identified in L. infantum protein extracts by antibodies in VL patients' sera, was cloned and its recombinant version (rEF1b) was expressed, purified and tested as a diagnostic marker for VL and TL. The post-therapeutic serological follow-up was also evaluated in treated and untreated VL and TL patients, when anti-rEF1b antibody levels were measured before and after treatment. Results showed that rEF1b was highly sensitive and specific to diagnose symptomatic and asymptomatic canine VL, as well as human TL and VL. In addition, low cross-reactivity was observed when sera from healthy subjects or leishmaniasis-related diseases patients were tested. The serological follow-up showed also that rEF1b-specific antibodies declined significantly after treatment, suggesting that this protein could be also evaluated as a prognostic marker for human leishmaniasis.


Asunto(s)
Enfermedades de los Perros/parasitología , Factor 1 Eucariótico de Iniciación/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/parasitología , Leishmaniasis Visceral/veterinaria , Proteínas Protozoarias/inmunología , Adulto , Animales , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/genética , Antígenos de Protozoos/inmunología , Reacciones Cruzadas , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/inmunología , Perros , Ensayo de Inmunoadsorción Enzimática , Factor 1 Eucariótico de Iniciación/genética , Femenino , Humanos , Leishmania infantum/genética , Leishmania infantum/aislamiento & purificación , Leishmaniasis/diagnóstico , Leishmaniasis/inmunología , Leishmaniasis/parasitología , Leishmaniasis/veterinaria , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/inmunología , Masculino , Persona de Mediana Edad , Proteínas Protozoarias/genética , Pruebas Serológicas
18.
Invest Ophthalmol Vis Sci ; 60(10): 3595-3605, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31425584

RESUMEN

Purpose: Uveal melanoma (UM) is characterized by multiple chromosomal rearrangements and recurrent mutated genes. The aim of this study was to investigate if copy number variations (CNV) alone and in combination with other genetic and clinico-histopathological variables can be used to stratify for disease-free survival (DFS) in enucleated patients with UM. Methods: We analyzed single nucleotide polymorphisms (SNP) array data of primary tumors and other clinical variables of 214 UM patients from the Rotterdam Ocular Melanoma Study (ROMS) cohort. Nonweighted hierarchical clustering of SNP array data was used to identify molecular subclasses with distinct CNV patterns. The subclasses associate with mutational status of BAP1, SF3B1, or EIF1AX. Cox proportional hazard models were then used to study the predictive performance of SNP array cluster-, mutation-, and clinico-histopathological data, and their combination for study endpoint risk. Results: Five clusters with distinct CNV patterns and concomitant mutations in BAP1, SF3B1, or EIF1AX were identified. The sample's cluster allocation contributed significantly to mutational status of samples in predicting the incidence of metastasis during a median of 45.6 (interquartile range [IQR]: 24.7-81.8) months of follow-up (P < 0.05) and vice versa. Furthermore, incorporating all data sources in one model yielded a 0.797 C-score during 100 months of follow-up. Conclusions: UM has distinct CNV patterns that correspond to different mutated driver genes. Incorporating clinico-histopathological, cluster and mutation data in the analysis results in good performance for UM-related DFS prediction.


Asunto(s)
Factor 1 Eucariótico de Iniciación/genética , Enucleación del Ojo , Melanoma/genética , Melanoma/cirugía , Fosfoproteínas/genética , Polimorfismo de Nucleótido Simple , Factores de Empalme de ARN/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/cirugía , Anciano , Variaciones en el Número de Copia de ADN , ADN de Neoplasias/genética , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Melanoma/diagnóstico , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Neoplasias de la Úvea/diagnóstico
19.
Nucleic Acids Res ; 47(15): 8282-8300, 2019 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-31291455

RESUMEN

eIF3 is a large multiprotein complex serving as an essential scaffold promoting binding of other eIFs to the 40S subunit, where it coordinates their actions during translation initiation. Perhaps due to a high degree of flexibility of multiple eIF3 subunits, a high-resolution structure of free eIF3 from any organism has never been solved. Employing genetics and biochemistry, we previously built a 2D interaction map of all five yeast eIF3 subunits. Here we further improved the previously reported in vitro reconstitution protocol of yeast eIF3, which we cross-linked and trypsin-digested to determine its overall shape in 3D by advanced mass-spectrometry. The obtained cross-links support our 2D subunit interaction map and reveal that eIF3 is tightly packed with its WD40 and RRM domains exposed. This contrasts with reported cryo-EM structures depicting eIF3 as a molecular embracer of the 40S subunit. Since the binding of eIF1 and eIF5 further fortified the compact architecture of eIF3, we suggest that its initial contact with the 40S solvent-exposed side makes eIF3 to open up and wrap around the 40S head with its extended arms. In addition, we mapped the position of eIF5 to the region below the P- and E-sites of the 40S subunit.


Asunto(s)
Factor 1 Eucariótico de Iniciación/química , Factor 3 de Iniciación Eucariótica/química , Factor 5 Eucariótico de Iniciación/química , Iniciación de la Cadena Peptídica Traduccional , Subunidades Ribosómicas Pequeñas de Eucariotas/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Sitios de Unión/genética , Microscopía por Crioelectrón , Factor 1 Eucariótico de Iniciación/genética , Factor 1 Eucariótico de Iniciación/metabolismo , Factor 3 de Iniciación Eucariótica/genética , Factor 3 de Iniciación Eucariótica/metabolismo , Factor 5 Eucariótico de Iniciación/genética , Factor 5 Eucariótico de Iniciación/metabolismo , Modelos Moleculares , Unión Proteica , Dominios Proteicos , Subunidades Ribosómicas Pequeñas de Eucariotas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
20.
Ophthalmology ; 126(7): 1045-1052, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30605742

RESUMEN

PURPOSE: To analyze the genetic profile of 6 cases of primary orbital melanoma with clinicopathologic correlation. DESIGN: Retrospective noninterventional study to analyze the genetic profile of 6 cases of primary orbital melanoma and to correlate the genetic findings with prognosis and clinicopathologic features. Inclusion criteria were patients with primary orbital melanoma with no evidence of primary eyelid skin, conjunctival, uveal, or remote melanoma at extraocular sites. PARTICIPANTS: The study involved 6 primary orbital melanomas from 6 patients. Four patients were exenterated and 2 had incisional biopsies performed. METHODS: Clinical notes and radiologic records were assessed to ascertain clinical tumor behavior. Sections were stained with hematoxylin-eosin and exposed to immunohistochemistry for S100, MelA, HMB45, Sox10, and BAP1. Melanoma DNA was exposed to array comparative genomic hybridization to assess gross chromosomal copy number changes. Point mutation assessment and Sanger sequencing were performed for GNAQ, GNA11, BRAF, NRAS, pTERT, SF3B1, and EIF1AX. MAIN OUTCOME MEASURES: These were the presence of gross chromosomal copy number changes and the presence of mutations in GNAQ, GNA11, BRAF, NRAS, pTERT, SF3B1, and EIF1AX; the presence of metastases and time period between diagnosis and death from melanoma; and correlation between the tumor genetic profile and the clinical behavior of the tumor. RESULTS: One of the 6 cases was clinically associated with oculodermal melanocytosis. Of the 6 patients, 3 died of melanoma metastases and 1 of unrelated causes; 2 remain alive at last review. Three of the 6 cases were histologically associated with a benign precursor lesion. All melanomas expressed S100, MelA, HMB45, and Sox10. One patient showed loss of BAP1 nuclear staining. The most frequent chromosomal gains across the 6 cases, in order of frequency, were 6p, 8q, 17q, 6q, and 20p. The most frequently lost regions were 1p, 9p, 16q, and 17p. One patient showed monsomy 3 and gain of 8q (and showed the BAP1 loss). Mutations were found in GNAQ (1 case), GNA11 (1 case), SF3B1 (2 cases), NRAS (2 cases), and pTERT (2 cases). CONCLUSIONS: The data point to 2 genetic groups for primary orbital conjunctiva melanoma-like and a uveal melanoma-like group. A larger study would help confirm this suggestion.


Asunto(s)
Melanoma/genética , Neoplasias Orbitales/genética , Adulto , Anciano , Anciano de 80 o más Años , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Factor 1 Eucariótico de Iniciación/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Factores de Empalme de ARN/genética , Estudios Retrospectivos , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...