RESUMO
Vault RNAs (vtRNAs) are small, about 100 nt long, polymerase III transcripts contained in the vault particles of eukaryotic cells. Presumably due to their enigmatic function, they have received little attention compared with most other noncoding RNA (ncRNA) families. Their poor sequence conservation makes homology search a complex and tedious task even within vertebrates. Here we report on a systematic and comprehensive analysis of this rapidly evolving class of ncRNAs in deuterostomes, providing a comprehensive collection of computationally predicted vtRNA genes. We find that all previously described vtRNAs are located at a conserved genomic locus linked to the protocadherin gene cluster, an association that is conserved throughout gnathostomes. Lineage-specific expansions to small vtRNA gene clusters are frequently observed in this region. A second vtRNA locus is syntenically conserved across eutherian mammals. The vtRNAs at the two eutherian loci exhibit substantial differences in their promoter structures, explaining their differential expression patterns in several human cancer cell lines. In teleosts, expression of several paralogous vtRNA genes, most but not all located at the syntenically conserved protocadherin locus, was verified by reverse transcriptase-polymerase chain reaction.
Assuntos
Evolução Molecular , RNA/genética , Partículas de Ribonucleoproteínas em Forma de Abóbada/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Sequência Conservada , Regulação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de RNA , Homologia de Sequência do Ácido Nucleico , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismoRESUMO
Urinary bladder carcinoma is one of the most frequent malignant tumour diseases. The frequency increases with advancing age. The knowledge increase about genetic changes in tumour cells opens the possibility of a new noninvasive diagnosis with the help of fluorescence in situ hybridization (FISH). Comparable data are obtained by application of different diagnostic methods (fluorescence in situ hybridization, urinary bladder cancer ELISA, urinary cytology, histopathology) at different times from 6 coincidentally selected patients (preoperation, biopsy material and postoperation). The FISH test proved to be a sensitive method and correlated with the histopathological data.
