AI Article Synopsis
- - The Tetrahymena thermophila ribozyme shows eight distinct intermediates during mechanical unfolding, with barriers that oppose this process, lasting seconds and requiring rupture forces of 10 to 30 piconewtons.
- - These barriers depend on magnesium and involve known interactions within and between different parts of the ribozyme.
- - The unpredictable nature of how these barriers are crossed may relate to how RNA structures respond to mechanical forces in processes like translation, mRNA export, and viral replication.
Article Abstract
Mechanical unfolding trajectories for single molecules of the Tetrahymena thermophila ribozyme display eight intermediates corresponding to discrete kinetic barriers that oppose mechanical unfolding with lifetimes of seconds and rupture forces between 10 and 30 piconewtons. Barriers are magnesium dependent and correspond to known intra- and interdomain interactions. Several barrier structures are "brittle," breakage requiring high forces but small (1 to 3 nanometers) deformations. Barrier crossing is stochastic, leading to variable unfolding paths. The response of complex RNA structures to locally applied mechanical forces may be analogous to the responses of RNA during translation, messenger RNA export from the nucleus, and viral replication.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1503549 | PMC |
| http://dx.doi.org/10.1126/science.1081338 | DOI Listing |
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