RESUMEN
The anatomy of the soft parts of Ilyocypris ramirezi Cusminsky & Whatley, 1996 is described and illustrated for the first time, based on findings of this species from water bodies in the shallow areas of the Llancanelo basin, south-west of Mendoza Province, Argentina. This species is common in Quaternary and extant environments of the Pampa and Patagonian regions. Its distribution is now extending in Argentina to the Central-West area, locally named "Cuyo region". Ilyocypris ramirezi is a good environmental indicator and constitutes a useful tool in paleolimnological studies.
Asunto(s)
Crustáceos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Argentina , Tamaño Corporal , Crustáceos/anatomía & histología , Crustáceos/crecimiento & desarrollo , Femenino , Masculino , Tamaño de los Órganos , América del SurRESUMEN
Small nuclear RNAs (snRNAs) are important factors in the functioning of eukaryotic cells that form several small complexes with proteins; these ribonucleoprotein particles (U snRNPs) have an essential role in the pre-mRNA processing, particularly in splicing, catalyzed by spliceosomes, large RNA-protein complexes composed of various snRNPs. Even though they are well defined in mammals, snRNPs are still not totally characterized in certain trypanosomatids as Trypanosoma cruzi. For this reason we subjected snRNAs (U2, U4, U5, and U6) from T. cruzi epimastigotes to molecular characterization by polymerase chain reaction (PCR) and reverse transcription-PCR. These amplified sequences were cloned, sequenced, and compared with those other of trypanosomatids. Among these snRNAs, U5 was less conserved and U6 the most conserved. Their respective secondary structures were predicted and compared with known T. brucei structures. In addition, the copy number of each snRNA in the T. cruzi genome was characterized by Southern blotting.
Asunto(s)
Genoma de Protozoos/genética , ARN Nuclear Pequeño/genética , Trypanosoma cruzi/genética , Animales , Southern Blotting , Clonación Molecular , Reacción en Cadena de la Polimerasa/métodos , Empalme del ARN , Análisis de Secuencia de ADNRESUMEN
Small nuclear RNAs (snRNAs) are important factors in the functioning of eukaryotic cells that form several small complexes with proteins; these ribonucleoprotein particles (U snRNPs) have an essential role in the pre-mRNA processing, particularly in splicing, catalyzed by spliceosomes, large RNA-protein complexes composed of various snRNPs. Even though they are well defined in mammals, snRNPs are still not totally characterized in certain trypanosomatids as Trypanosoma cruzi. For this reason we subjected snRNAs (U2, U4, U5, and U6) from T. cruzi epimastigotes to molecular characterization by polymerase chain reaction (PCR) and reverse transcription-PCR. These amplified sequences were cloned, sequenced, and compared with those other of trypanosomatids. Among these snRNAs, U5 was less conserved and U6 the most conserved. Their respective secondary structures were predicted and compared with known T. brucei structures. In addition, the copy number of each snRNA in the T. cruzi genome was characterized by Southern blotting.
Asunto(s)
Animales , Genoma de Protozoos/genética , ARN Nuclear Pequeño/genética , Trypanosoma cruzi/genética , Southern Blotting , Clonación Molecular , Reacción en Cadena de la Polimerasa/métodos , Empalme del ARNRESUMEN
Pre-mRNA maturation in trypanosomatids occurs through a process called trans-splicing which involves excision of introns and union of exons in two independent transcripts. For the first time, we present the standardization of Trypanosoma cruzi permeable cells (Y strain) as a model for trans-splicing study of mRNAs in trypanosomes, following by RNase protection reaction, which localizes the SL exon and intron. This trans-splicing reaction in vitro was also used to analyze the influence of NFOH-121, a nitrofurazone-derivative, on this mechanism. The results suggested that the prodrug affects the RNA processing in these parasites, but the trans-splicing reaction still occurred.
Asunto(s)
Nitrofurazona/análogos & derivados , Nitrofurazona/farmacología , Empalme del ARN/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , ARN Protozoario/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma cruzi/genética , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Exones/genética , Intrones/genética , Factores de Tiempo , Transcripción Genética/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/crecimiento & desarrolloRESUMEN
Pre-mRNA maturation in trypanosomatids occurs through a process called trans-splicing which involves excision of introns and union of exons in two independent transcripts. For the first time, we present the standardization of Trypanosoma cruzi permeable cells (Y strain) as a model for trans-splicing study of mRNAs in trypanosomes, following by RNase protection reaction, which localizes the SL exon and intron. This trans-splicing reaction in vitro was also used to analyze the influence of NFOH-121, a nitrofurazone-derivative, on this mechanism. The results suggested that the prodrug affects the RNA processing in these parasites, but the trans-splicing reaction still occurred.