SURVEY AND SUMMARY: Downstream elements of mammalian pre-mRNA polyadenylation signals: primary, secondary and higher-order structures
AUTOR(ES)
Zarudnaya, Margarita I.
FONTE
Oxford University Press
RESUMO
Primary, secondary and higher-order structures of downstream elements of mammalian pre-mRNA polyadenylation signals [poly(A) signals] are re viewed. We have carried out a detailed analysis on our database of 244 human pre-mRNA poly(A) signals in order to characterize elements in their downstream regions. We suggest that the downstream region of the mammalian pre-mRNA poly(A) signal consists of various simple elements located at different distances from each other. Thus, the downstream region is not described by any precise consensus. Searching our database, we found that ∼80% of pre-mRNAs with the AAUAAA or AUUAAA core upstream elements contain simple downstream elements, consisting of U-rich and/or 2GU/U tracts, the former occurring ∼2-fold more often than the latter. Approximately one-third of the pre-mRNAs analyzed here contain sequences that may form G-quadruplexes. A substantial number of these sequences are located immediately downstream of the poly(A) signal. A possible role of G-rich sequences in the polyadenylation process is discussed. A model of the secondary structure of the SV40 late pre-mRNA poly(A) signal downstream region is presented.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=149834Documentos Relacionados
- Sequences downstream of AAUAAA signals affect pre-mRNA cleavage and polyadenylation in vitro both directly and indirectly.
- Distinctive higher-order chromatin structure at mammalian centromeres
- Formation of higher-order secondary and tertiary chromatin structures by genomic mouse mammary tumor virus promoters
- Chemical probes for higher-order structure in RNA.
- Identification of pre-mRNA polyadenylation sites in Saccharomyces cerevisiae.
