Unwinding the twister ribozyme: from structure to mechanism.

ABSTRACT: The twister ribozyme motif has been identified by bioinformatic means very recently. Currently, four crystal structures with ordered active sites together with a series of chemical and biochemical data provide insights into how this RNA accomplishes its efficient self-cleavage. Of particular interest for a mechanistic proposal are structural distinctions observed in the active sites that concern the conformation of the U-A cleavage site dinucleotide (in-line alignment of the attacking 2'-O nucleophile to the to-be-cleaved PO5' bond versus suboptimal alignments) as well as the presence/absence of Mg2+ ions at the scissile phosphate. All structures support the notion that an active site guanine and the conserved adenine at the cleavage site are important contributors to cleavage chemistry,

SUBMITTER: Gebetsberger J 

PROVIDER: S-EPMC5408937 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature