A novel RNA pentaloop fold involved in targeting ADAR2.
Stefl, R., Allain, F.H.(2005) RNA 11: 592-597
- PubMed: 15840813 
- DOI: https://doi.org/10.1261/rna.7276805
- Primary Citation of Related Structures:  
1YSV - PubMed Abstract: 
Adenosine deaminases that act on RNA (ADARs) catalyze the site-specific conversion of adenosine to inosine in primary mRNA transcripts, thereby affecting coding potential of mature mRNAs. Structural determinants that define the adenosine moieties for specific ADARs-mediated deaminations are currently unknown. We report the solution structure of the central region of the human R/G stem-loop pre-mRNA, a natural ADAR2 substrate encoding the subunit B of the glutamate receptor (R/G site). The structure reveals that the GCU(A/C)A pentaloop that is conserved in mammals and birds adopts a novel fold. The fold is stabilized by a complex interplay of hydrogen bonds and stacking interactions. We propose that this new pentaloop structure is an important determinant of the R/G site recognition by ADAR2.
Organizational Affiliation: 
Institute of Molecular Biology and Biophysics, Swiss Federal Institute of Technology Zurich, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.