Donghi D, et al. (2013) The structural stabilization of the kappa three-way junction by Mg(II) represents the first step in the folding of a group II intron. Nucleic Acids Res 41(4):2489-504
Abstract: Folding of group II introns is characterized by a first slow compaction of domain 1 (D1) followed by the rapid docking of other domains to this scaffold. D1 compaction initiates in a small subregion encompassing the kappa and zeta elements. These two tertiary elements are also the major interaction sites with domain 5 to form the catalytic core. Here, we provide the first characterization of the structure adopted at an early folding step and show that the folding control element can be narrowed down to the three-way junction with the kappa motif. In our nuclear magnetic resonance studies of this substructure derived from the yeast mitochondrial group II intron Sc.ai5gamma, we show that a high affinity Mg(II) ion stabilizes the kappa element and enables coaxial stacking between helices d' and d'', favoring a rigid duplex across the three-way junction. The kappa-element folds into a stable GAAA-tetraloop motif and engages in A-minor interactions with helix d'. The addition of cobalt(III)hexammine reveals three distinct binding sites. The Mg(II)-promoted structural rearrangement and rigidification of the D1 core can be identified as the first micro-step of D1 folding.
|Status: Published||Type: Journal Article||PubMed ID: 23275550|
Topics addressed in this paper
- To find other papers on a gene and topic, click on the colored ball in the appropriate box.
- displays other papers with information about that topic for that gene.
- displays other papers in SGD that are associated with that topic.
The topic is addressed in these papers but does not describe a specific gene or chromosomal feature.
- To go to the Locus page for a gene, click on the gene name.
|Topics||Genes linked to topics|