Abstract：
:Intron-encoded U17 RNA is a member of the H/ACA box class of small nucleolar RNAs (snoRNAs) involved in ribosomal RNA (rRNA) maturation. U17 snoRNA shows typical characteristics of guide RNAs, which specify sites of pseudouridylation on the precursor rRNA (pre-rRNA). However, in spite of the presence of H and ACA boxes and short regions complementary to the pre-rRNA, its secondary structure does not show any evident pseudouridylation pocket. Moreover, its length is larger than the typical one of snoRNAs and it shows a more complex secondary structure compared to the canonical hairpin-hinge-hairpin-tail architecture. Greater knowledge of eukaryotic U17 snoRNA structure is needed to understand its precise function. Comparative molecular studies of this snoRNA with different vertebrates is still limited to a few cases. With the aim of increasing our understanding of the U17 snoRNA secondary structure, we cloned the U17 snoRNA coding sequence from 10 additional vertebrate taxa. On the basis of structure homology derived from sequence comparison and thermodynamic prediction, we propose a vertebrate consensus secondary structure and novel conserved sequence boxes for U17 snoRNA. Host gene localization of U17 coding sequence and its ability to serve as a guide sequence for RNA/RNA interaction has been evolutionarily traced from fish to mammals. It is interesting to note that turtle U17 snoRNAs show a noncanonical ACA box, mainly consisting in the GCA box. Microinjections in X. laevis oocytes of in vitro synthesized turtle transcripts containing the U17 RNA sequence which have canonical ACA, wild-type GCA, and mutated CCA and UCA boxes resulted in efficient production of mature U17 snoRNA.
journal_name
J Mol Evoljournal_title
Journal of molecular evolutionauthors
Cervelli M,Cecconi F,Giorgi M,Annesi F,Oliverio M,Mariottini Pdoi
10.1007/s00239-001-0065-2keywords:
subject
Has Abstractpub_date
2002-02-01 00:00:00pages
166-79issue
2eissn
0022-2844issn
1432-1432journal_volume
54pub_type
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更新日期：2011-03-01 00:00:00
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pub_type： 杂志文章
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pub_type： 杂志文章
doi：10.1007/s002399910031
更新日期：2000-03-01 00:00:00
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pub_type： 杂志文章
doi：10.1007/BF00163805
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pub_type： 杂志文章
doi：10.1007/BF02603122
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