RESUMO
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.
Assuntos
Crustáceos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Argentina , Tamanho Corporal , Crustáceos/anatomia & histologia , Crustáceos/crescimento & desenvolvimento , Feminino , Masculino , Tamanho do Órgão , América do SulRESUMO
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.
Assuntos
Genoma de Protozoário/genética , RNA Nuclear Pequeno/genética , Trypanosoma cruzi/genética , Animais , Southern Blotting , Clonagem Molecular , Reação em Cadeia da Polimerase/métodos , Splicing de RNA , Análise de Sequência de DNARESUMO
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.
Assuntos
Animais , Genoma de Protozoário/genética , RNA Nuclear Pequeno/genética , Trypanosoma cruzi/genética , Southern Blotting , Clonagem Molecular , Reação em Cadeia da Polimerase/métodos , Splicing de RNARESUMO
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.
Assuntos
Nitrofurazona/análogos & derivados , Nitrofurazona/farmacologia , Splicing de RNA/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA de Protozoário/efeitos dos fármacos , Tripanossomicidas/farmacologia , Trypanosoma cruzi/genética , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Éxons/genética , Íntrons/genética , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/crescimento & desenvolvimentoRESUMO
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.