Cryoelectron microscopy structures of the ribosome complex in intermediate states during tRNA translocation.
نویسندگان
چکیده
mRNA-tRNA translocation is a central and highly regulated process during translational elongation. Along with the mRNA, tRNA moves through the ribosome in a stepwise fashion. Using cryoelectron microscopy on ribosomes with a P-loop mutation, we have identified novel structural intermediates likely to exist transiently during translocation. Our observations suggest a mechanism by which the rate of translocation can be regulated.
منابع مشابه
The process of mRNA-tRNA translocation.
In the elongation cycle of translation, translocation is the process that advances the mRNA-tRNA moiety on the ribosome, to allow the next codon to move into the decoding center. New results obtained by cryoelectron microscopy, interpreted in the light of x-ray structures and kinetic data, allow us to develop a model of the molecular events during translocation.
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 108 12 شماره
صفحات -
تاریخ انتشار 2011