Comparative single-turnover kinetic analyses of trans-cleaving hammerhead ribozymes with naturally derived non-conserved sequence motifs.
trans-Cleaving hammerhead ribozyme variants were generated with mimicked non-conserved internal loop motifs derived from five structurally diverse natural cis-cleaving ribozymes. Most modified trans-cleaving variants showed enhanced single-turnover cleavage rates relative to minimal counterparts that lack tertiary interactions between internal loop motifs I and II, and relative to controls with sequence changes in loop I. The trans-cleaving ribozyme derived from the positive strand of peach latent mosaic viroid had the highest observed cleavage rate, suggesting a structurally optimized motif that facilitates rapid formation of the ribozyme catalytic center in a trans-reaction.
Weinberg
Marc S
MS
Division of Molecular Biology, Beckman Research Institute of the City of Hope, Graduate School of Biological Sciences, Duarte, CA 91010, USA.
Rossi
John J
JJ
D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D017124:Conserved Sequence; D007700:Kinetics; D018716:Molecular Mimicry; D009029:Mosaic Viruses / Q000201:enzymology; D009690:Nucleic Acid Conformation; D016337:RNA, Catalytic / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D014772:Viroids / Q000201:enzymology
D016337:RNA, Catalytic; C427204:hammerhead ribozyme