3IIN

Plasticity of the kink turn structural motif

Summary for 3IIN

• Entry DOI: 10.2210/pdb3iin/pdb
• Descriptor: U1 small nuclear ribonucleoprotein A, Group I intron, DNA/RNA (5'-R(*AP*AP*GP*CP*CP*AP*CP*AP*CP*AP*GP*AP*CP*C)-D(P*AP*GP*A)-R(P*CP*GP*GP*CP*C)-3'), ... (7 entities in total)
• Functional Keywords: group i intron, azoarcus, ribozyme, ligation, kink turn, acetylation, mrna processing, mrna splicing, nucleus, phosphoprotein, ribonucleoprotein, rna-binding, spliceosome, rna binding protein/dna, rna complex, rna binding protein-dna-rna complex, rna binding protein/dna/rna
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus: P09012
• Total number of polymer chains: 4
• Total formula weight: 83514.37

Authors

Lipchock, S.V.,Strobel, S.A.,Antonioli, A.H.,Cochrane, J.C. (deposition date: 2009-08-02, release date: 2010-03-09, Last modification date: 2023-09-06)

Primary citation

Antonioli, A.H.,Cochrane, J.C.,Lipchock, S.V.,Strobel, S.A.
Plasticity of the RNA kink turn structural motif.
Rna, 16:762-768, 2010

PubMed Abstract: The kink turn (K-turn) is an RNA structural motif found in many biologically significant RNAs. While most examples of the K-turn have a similar fold, the crystal structure of the Azoarcus group I intron revealed a novel RNA conformation, a reverse kink turn bent in the direction opposite that of a consensus K-turn. The reverse K-turn is bent toward the major grooves rather than the minor grooves of the flanking helices, yet the sequence differs from the K-turn consensus by only a single nucleotide. Here we demonstrate that the reverse bend direction is not solely defined by internal sequence elements, but is instead affected by structural elements external to the K-turn. It bends toward the major groove under the direction of a tetraloop-tetraloop receptor. The ability of one sequence to form two distinct structures demonstrates the inherent plasticity of the K-turn sequence. Such plasticity suggests that the K-turn is not a primary element in RNA folding, but instead is shaped by other structural elements within the RNA or ribonucleoprotein assembly.

PubMed: 20145044
DOI: 10.1261/rna.1883810

Experimental method

X-RAY DIFFRACTION (4.18 Å)