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Numerous small hammerhead ribozyme variants associated with Penelope-like retrotransposons cleave RNA as dimers.

ABSTRACT: Hammerhead ribozymes represent the most common of the 9 natural classes of self-cleaving RNAs. The hammerhead catalytic core includes 11 highly-conserved nucleotides located largely within the unpaired regions of a junction formed by stems I, II and III. The vast majority of previously reported examples carry an additional pseudoknot or other tertiary interactions between nucleotides that precede stem I and nucleotides in the loop of stem II. These extra contacts are critical for high-speed RNA catalysis. Herein, we report the discovery of ?150,000 additional variant hammerhead representatives that exhibit diminished stem III substructures. These variants are frequently associated with Penelope-like retrotransposons, which are a type of mobile genetic element. Kinetic analyses indicate that these RNAs form dimers to cleave RNA.

SUBMITTER: Lunse CE

PROVIDER: S-EPMC5785218 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Numerous small hammerhead ribozyme variants associated with Penelope-like retrotransposons cleave RNA as dimers.

Lünse Christina E CE Weinberg Zasha Z Weinberg Zasha Z Breaker Ronald R RR

RNA biology 20171103 11

Hammerhead ribozymes represent the most common of the 9 natural classes of self-cleaving RNAs. The hammerhead catalytic core includes 11 highly-conserved nucleotides located largely within the unpaired regions of a junction formed by stems I, II and III. The vast majority of previously reported examples carry an additional pseudoknot or other tertiary interactions between nucleotides that precede stem I and nucleotides in the loop of stem II. These extra contacts are critical for high-speed RNA ...[more]

PMID: 27858507

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