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1.
Int J Mol Sci ; 23(6)2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35328692

RESUMEN

The long noncoding RNA (lncRNA) telomeric repeat-containing RNA (TERRA) has been associated with telomeric homeostasis, telomerase recruitment, and the process of chromosome healing; nevertheless, the impact of this association has not been investigated during the carcinogenic process. Determining whether changes in TERRA expression are a cause or a consequence of cell transformation is a complex task because studies are usually carried out using either cancerous cells or tumor samples. To determine the role of this lncRNA in cellular aging and chromosome healing, we evaluated telomeric integrity and TERRA expression during the establishment of a clone of untransformed myeloid cells. We found that reduced expression of TERRA disturbed the telomeric homeostasis of certain loci, but the expression of the lncRNA was affected only when the methylation of subtelomeric bivalent chromatin domains was compromised. We conclude that the disruption in TERRA homeostasis is a consequence of cellular transformation and that changes in its expression profile can lead to telomeric and genomic instability.


Asunto(s)
ARN Largo no Codificante , Homeostasis del Telómero , Cromatina/genética , Heterocromatina , Metilación , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Telómero/genética , Telómero/metabolismo
2.
FEBS J ; 289(7): 1858-1875, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34739170

RESUMEN

Cell cycle progression requires control of the abundance of several proteins and RNAs over space and time to properly transit from one phase to the next and to ensure faithful genomic inheritance in daughter cells. The proteasome, the main protein degradation system of the cell, facilitates the establishment of a proteome specific to each phase of the cell cycle. Its activity also strongly influences transcription. Here, we detected the upregulation of repetitive RNAs upon proteasome inhibition in human cancer cells using RNA-seq. The effect of proteasome inhibition on centromeres was remarkable, especially on α-Satellite RNAs. We showed that α-Satellite RNAs fluctuate along the cell cycle and interact with members of the cohesin ring, suggesting that these transcripts may take part in the regulation of mitotic progression. Next, we forced exogenous overexpression and used gapmer oligonucleotide targeting to demonstrate that α-Sat RNAs have regulatory roles in mitosis. Finally, we explored the transcriptional regulation of α-Satellite DNA. Through in silico analyses, we detected the presence of CCAAT transcription factor-binding motifs within α-Satellite centromeric arrays. Using high-resolution three-dimensional immuno-FISH and ChIP-qPCR, we showed an association between the α-Satellite upregulation and the recruitment of the transcription factor NFY-A to the centromere upon MG132-induced proteasome inhibition. Together, our results show that the proteasome controls α-Satellite RNAs associated with the regulation of mitosis.


Asunto(s)
Complejo de la Endopetidasa Proteasomal , Satélite de ARN , Centrómero/genética , Centrómero/metabolismo , ADN Satélite/genética , Humanos , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Satélite de ARN/genética , Regulación hacia Arriba
3.
Genome Biol Evol ; 12(12): 2355-2369, 2020 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-33045056

RESUMEN

MicroRNAs are important regulators of gene expression in eukaryotes. Previously, we reported that in Phaseolus vulgaris, the precursor for miR2119 is located in the same gene as miR398a, conceiving a dicistronic MIR gene. Both miRNA precursors are transcribed and processed from a single transcript resulting in two mature microRNAs that regulate the mRNAs encoding ALCOHOL DEHYDROGENASE 1 (ADH1) and COPPER-ZINC SUPEROXIDE DISMUTASE 1 (CSD1). Genes for miR398 are distributed throughout the spermatophytes; however, miR2119 is only found in Leguminosae species, indicating its recent emergence. Here, we used public databases to explore the presence of the miR2119 sequence in several plant species. We found that miR2119 is present only in specific clades within the Papilionoideae subfamily, including important crops used for human consumption and forage. Within this subfamily, MIR2119 and MIR398a are found together as a single gene in the genomes of the Millettioids and Hologalegina. In contrast, in the Dalbergioids MIR2119 is located in a different locus from MIR398a, suggesting this as the ancestral genomic organization. To our knowledge, this is a unique example where two separate MIRNA genes have merged to generate a single polycistronic gene. Phylogenetic analysis of ADH1 gene sequences in the Papilionoideae subfamily revealed duplication events resulting in up to four ADH1 genes in certain species. Notably, the presence of MIR2119 correlates with the conservation of target sites in particular ADH1 genes in each clade. Our results suggest that post-transcriptional regulation of ADH1 genes by miR2119 has contributed to shaping the expansion and divergence of this gene family in the Papilionoideae. Future experimental work on ADH1 regulation by miR2119 in more legume species will help to further understand the evolutionary history of the ADH1 gene family and the relevance of miRNA regulation in this process.


Asunto(s)
Alcohol Deshidrogenasa/genética , Fabaceae/genética , Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Duplicación de Gen , Filogenia
4.
Methods Mol Biol ; 1932: 121-129, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30701496

RESUMEN

The study of regulatory small RNAs, such as siRNAs and microRNAs in plants, has necessitated methods tailored to their unique features. Their analysis demands the use of sensitive and quantitative methods for their detection. The use of Northern blot hybridization offers an attractive alternative to address qualitative as well as quantitative features. We highlight the advantages and shortcomings of this method and offer a detailed description of the techniques that best work in our hands, considering their use for the study of several small RNAs in multiple samples. We enumerate relevant details as well as cautionary comments in cases where we have detected potential difficulties.


Asunto(s)
MicroARNs/genética , Plantas/genética , ARN de Planta/genética , Northern Blotting/métodos , Regulación de la Expresión Génica de las Plantas/genética , Hibridación de Ácido Nucleico/genética , ARN Interferente Pequeño/genética
5.
Plant Cell Environ ; 42(1): 133-144, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29626361

RESUMEN

Plant microRNAs are commonly encoded in transcripts containing a single microRNA precursor. Processing by DICER-LIKE 1 and associated factors results in the production of a small RNA, followed by its incorporation into an AGO-containing protein complex to guide silencing of an mRNA possessing a complementary target sequence. Certain microRNA loci contain more than one precursor stem-loop structure, thus encoding more than one microRNA in the same transcript. Here, we describe a unique case where the evolutionary conserved miR398a is encoded in the same transcript as the legume-specific miR2119. The dicistronic arrangement found in common bean was also observed in other legumes. In Phaseolus vulgaris, mature miR398 and miR2119 are repressed in response to water deficit, and we demonstrate that both are functional as they target the mRNAs for CSD1 and ADH1, respectively. Our results indicate that the repression of miR398 and miR2119 leads to coordinated up-regulation of CSD1 and ADH1 mRNAs in response to water deficit in common bean and possibly in other legumes. Furthermore, we show that miRNA directed CSD1 and ADH1 mRNAs up-regulation also occurs when common bean plants are exposed to flooding, suggesting that plant redox status and fermentation metabolism must be closely coordinated under different adverse conditions.


Asunto(s)
Alcohol Deshidrogenasa/metabolismo , MicroARNs/metabolismo , Phaseolus/metabolismo , Proteínas de Plantas/metabolismo , Precursores del ARN/metabolismo , Superóxido Dismutasa/metabolismo , Alcohol Deshidrogenasa/genética , Deshidratación , Regulación de la Expresión Génica de las Plantas/genética , MicroARNs/genética , Phaseolus/fisiología , Proteínas de Plantas/genética , Reacción en Cadena de la Polimerasa , Precursores del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Superóxido Dismutasa/genética
6.
Zootaxa ; 3947(3): 386-96, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25947743

RESUMEN

We describe a new species, Erythrodiplax laselva (Libellulidae), that breeds in bromeliads and Cochliostema (Commelinaceae) in the eastern lowlands of Costa Rica. The closest known relative is thought to be E. castanea, widespread in Central and South America, and not E. bromeliicola, which is known to breed in bromeliads in Cuba and Jamaica. The male, female, genitalia, and larva are described and illustrated.


Asunto(s)
Bromeliaceae , Odonata/anatomía & histología , Odonata/clasificación , Distribución Animal , Animales , Costa Rica , Femenino , Larva/anatomía & histología , Larva/clasificación , Masculino
7.
Int. j. morphol ; 28(3): 803-810, Sept. 2010. ilus
Artículo en Español | LILACS | ID: lil-577188

RESUMEN

Actualmente la cuantificación de la masa muscular es un área de estudio que ocupa distintas disciplinas científicas tanto de la salud como de las ciencias del deporte por ser un componente de la masa corporal que está en íntima relación con aspectos de la salud y del rendimiento deportivo. Existe una gran variedad de métodos y ecuaciones para su estimación pero la aplicación de las mismas no siempre resulta la más adecuada. El propósito de nuestro estudio es determinar la masa muscular en 37 jugadores de bádminton españoles, a través de técnicas antropométricas y hallar la fórmula más apropiada para dicha población. Fueron evaluadas 55 variables antropométricas: peso, estatura. perímetros, diámetros, longitudes, alturas y pliegues cutáneos. La composición corporal estimada de los jugadores de bádminton fue de 44 por ciento para la masa muscular y de 13 por ciento para la masa grasa. Los resultados indican que la táctica de fraccionamiento tetracompartimental que mejor se ajusta y concuerda con el peso real estimado con balanza es la siguiente: Masa Residual (Wurch), Masa Ósea (Rocha), Masa Grasa (Faulkner) y Masa Muscular (Drinkwater o Kerr).


The quantification of muscle mass is an area of study that addresses various scientific disciplines from health and sport science as a component of body mass that is in close connection with aspects of health and athletic performance. A variety of methods and equations for their estimation, but implementing them is not always the most appropriate. The purpose of our study is to determine the muscle mass of 37 badminton players of Spain, through anthropometric techniques and finding the most appropriate for this population. We studied 37 badminton players follow the protocol ISAK. Anthropometric variables were evaluated: weight, height, girth, breadth, lengths, heights and skin fold. For the fractionation of body composition in four components were combined different formulas to find the strategy that best fits and matches the estimated weight scale. We used the Wurch’s formula for residual mass, Rochas for bone mass, Brozek’s fat mass and to the muscle mass was concluded that the most appropriate for this population with those of Kerr’s. Body composition was estimated for our population: 10.8 percent bone mass, 15.3 percent residual mass, 13.2 percent fat mass and 44.9 percent muscle mass.


Asunto(s)
Humanos , Masculino , Adulto , Antropometría/métodos , Composición Corporal , Músculo Esquelético/anatomía & histología , Deportes de Raqueta , Índice de Masa Corporal , Deportes
8.
Plant Mol Biol ; 70(4): 385-401, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19353277

RESUMEN

MicroRNAs (miRNAs) are small RNA molecules recognized as important regulators of gene expression. Although plant miRNAs have been extensively studied in model systems, less is known in other plants with limited genome sequence data. We are interested in the identification of miRNAs in Phaseolus vulgaris (common bean) to uncover different plant strategies to cope with adverse conditions and because of its relevance as a crop in developing countries. Here we present the identification of conserved and candidate novel miRNAs in P. vulgaris present in different organs and growth conditions, including drought, abscisic acid treatment, and Rhizobium infection. We also identified cDNA sequences in public databases that represent the corresponding miRNA precursors. In addition, we predicted and validated target mRNAs amongst reported EST and cDNAs for P. vulgaris. We propose that the novel miRNAs present in common bean and other legumes, are involved in regulation of legume-specific processes including adaptation to diverse external cues.


Asunto(s)
MicroARNs/genética , Phaseolus/genética , ARN de Planta/genética , Ácido Abscísico/farmacología , Secuencia de Bases , Northern Blotting , Frío , Secuencia Conservada , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Biblioteca de Genes , MicroARNs/química , MicroARNs/metabolismo , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Phaseolus/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , ARN de Planta/química , ARN de Planta/metabolismo , Semillas/efectos de los fármacos , Semillas/genética , Homología de Secuencia de Ácido Nucleico , Cloruro de Sodio/farmacología , Glycine max/genética , Agua/farmacología
9.
Acta pediátr. Méx ; 18(5): 227-31, sept.-oct. 1997. ilus
Artículo en Español | LILACS | ID: lil-217469

RESUMEN

La uncinariasis es una parasitosis transmitida por el suelo que afecta aproximadamente a mil millones de personas en los países subdesarrollados. En el humano, esta enfermedad se caracteriza por verter grandes cantidades de sangre hacia el tubo digestivo del huésped. La hemorragia gastrointestinal grave debida a la infestación por Necator americanus es una complicación observada en niños pequeños; sin embargo, el íleo paralítico es un suceso muy raro y puede manifestarse como una urgencia quirúrgica. Se presentan los casos de dos niños que sufrieron peritonitis secundaria a uncinariasis. Uno de ellos sufrió además hemorragia grave. El otro, oclusión duodenal que requirió una duodenoyeyunoanastomosis laterolateral como procedimiento paliativo


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Infecciones por Uncinaria/complicaciones , Infecciones por Uncinaria/diagnóstico , Íleon/parasitología , Peritonitis/etiología , Peritonitis/parasitología
11.
Rev. invest. clín ; Rev. invest. clín;38(3): 303-6, jul.-sept. 1986.
Artículo en Español | LILACS | ID: lil-104135

RESUMEN

Se describe el caso de una lesión esofágica, manifestada por obstrucción y sangrado, que en le estudio postoperatorio histopatológico fue reportado como, adenocarcinoide y adenocarcinoma in situ, proveniente de epitelio de Barret. Se discute la naturaleza de la lesión y se hace énfasis en la rareza de la asociación de lesiones, siendo esta caso, hasta nuestro conocimiento, el primero descrito en la literatura que conjunta las lesiones


Asunto(s)
Persona de Mediana Edad , Humanos , Masculino , Adenocarcinoma/complicaciones , Esófago de Barrett/complicaciones , Tumor Carcinoide/complicaciones , Carcinoma in Situ/complicaciones , Enfermedades del Esófago/complicaciones , Neoplasias Esofágicas/complicaciones
12.
Rev. invest. clín ; Rev. invest. clín;38(2): 189-92, abr.-jun. 1986. ilus
Artículo en Español | LILACS | ID: lil-104150

RESUMEN

Se informa un caso de trombocitopenia post-transfusión de sangre de banco; se manifestó por hemorragia intra-abdominal masiva, de múltiples sitios que fue imposible de controlar con los métodos usuales de hemostasis. Se llevó a cabo empacamiento abdominal total con compresas abdominales con lo que se controló satisfactoriamente la hemoragia y 36 horas después se llevó a cabo cirugía para la extracción de las empresas, evolucionando adecuadamente. Se demuestra la utilidad de este procedimiento como medida heroica en este tipo de sangrado transoperatorio


Asunto(s)
Adulto , Humanos , Femenino , Hemorragia Gastrointestinal/terapia , Hemostasis Quirúrgica/métodos , Enfermedades del Colon/cirugía , Fístula Gástrica/cirugía , Fístula Intestinal/cirugía , Complicaciones Intraoperatorias/terapia , Técnicas de Sutura
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