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Structural and thermodynamic signatures that define pseudotriloop RNA hairpins.

ABSTRACT: Pseudotriloop (PTL) structures in RNAs have been recognized as essential elements in RNA folding and recognition of proteins. PTL structures are derived from hexaloops by formation of a cross-loop base pair leaving a triloop and 3' bulged out residue. Despite their common presence and functional importance, insufficient structural and thermodynamic data are available that can be used to predict formation of PTLs from sequence alone. Using NMR spectroscopy and UV-melting data we established factors that contribute to the formation and stability of PTL structures derived from hepatitis B virus and human foamy virus. The NMR data show that, besides the cross-loop base pair, also a 3' pyrimidine bulge and a G-C loop-closing base pair are primary determinants of PTL formation. By changing the G-C closing base pair into C-G, the PTL switches into a hexaloop. Comparison of these rules with regular triloop hairpins and PTLs from other sources is discussed as well as the conservation of a PTL in human foamy virus and other spumaretroviruses.

SUBMITTER: van der Werf R

PROVIDER: S-EPMC3884659 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Structural and thermodynamic signatures that define pseudotriloop RNA hairpins.

van der Werf Ramon R Wijmenga Sybren S SS Heus Hans A HA Olsthoorn René C L RC

RNA (New York, N.Y.) 20131024 12

Pseudotriloop (PTL) structures in RNAs have been recognized as essential elements in RNA folding and recognition of proteins. PTL structures are derived from hexaloops by formation of a cross-loop base pair leaving a triloop and 3' bulged out residue. Despite their common presence and functional importance, insufficient structural and thermodynamic data are available that can be used to predict formation of PTLs from sequence alone. Using NMR spectroscopy and UV-melting data we established facto ...[more]

PMID: 24158793

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Dataset Information

Structural and thermodynamic signatures that define pseudotriloop RNA hairpins.

Publications

Structural and thermodynamic signatures that define pseudotriloop RNA hairpins.

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