U1 small nuclear RNA and spliceosomal introns in Euglena gracilis
| Autor: | David G. Breckenridge, Spencer J. Greenwood, Yoh-ichi Watanabe, Michael W. Gray, Murray N. Schnare |
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| Rok vydání: | 1999 |
| Předmět: |
Small RNA
DNA Complementary Nuclear gene Euglena gracilis Molecular Sequence Data ved/biology.organism_classification_rank.species Biology Polymerase Chain Reaction RNA Small Nuclear Animals Base Pairing Conserved Sequence Fibrillarin Genetics Multidisciplinary Base Sequence ved/biology Intron RNA Biological Sciences Introns RNA splicing Spliceosomes Nucleic Acid Conformation RNA Protozoan Small nuclear RNA |
| Zdroj: | Proceedings of the National Academy of Sciences. 96:852-856 |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | In the flagellated protozoon Euglena gracilis , characterized nuclear genes harbor atypical introns that usually are flanked by short repeats, adopt complex secondary structures in pre-mRNA, and do not obey the GT-AG rule of conventional cis-spliced introns. In the nuclear fibrillarin gene of E. gracilis , we have identified three spliceosomal-type introns that have GT-AG consensus borders. Furthermore, we have isolated a small RNA from E. gracilis and propose, on the basis of primary and secondary structure comparisons, that it is a homolog of U1 small nuclear RNA, an essential component of the cis-spliceosome in higher eukaryotes. Conserved sequences at the 5′ splice sites of the fibrillarin introns can potentially base pair with Euglena U1 small nuclear RNA. Our observations demonstrate that spliceosomal GT-AG cis-splicing occurs in Euglena , in addition to the nonconventional cis-splicing and spliced leader trans-splicing previously recognized in this early diverging unicellular eukaryote. |
| Databáze: | OpenAIRE |
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