A single-stranded junction modulates nanosecond motional ordering of the substrate recognition duplex of a group I ribozyme.
نویسندگان
چکیده
Rigid spinning: Site-directed spin-labeling studies using a rigid nitroxide spin label (Ç) reveal that both length and sequence of a single-stranded junction (J1/2) modulate nanosecond motional ordering of the substrate-recognition duplex (P1) of the 120 kD group I ribozyme. The studies demonstrate an approach for experimental measurements of nanosecond dynamics in high-molecular-weight RNA complexes.
منابع مشابه
Motions of the substrate recognition duplex in a group I intron assessed by site-directed spin labeling.
The Tetrahymena group I intron recognizes its oligonucleotide substrate in a two-step process. First, a substrate recognition duplex, called the P1 duplex, is formed. The P1 duplex then docks into the prefolded ribozyme core by forming tertiary contacts. P1 docking controls both the rate and the fidelity of substrate cleavage and has been extensively studied as a model for the formation of RNA ...
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عنوان ژورنال:
- Chembiochem : a European journal of chemical biology
دوره 14 14 شماره
صفحات -
تاریخ انتشار 2013