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In vitro substrate specificities of 3'-5' polymerases correlate with biological outcomes of tRNA 5'-editing reactions.

ABSTRACT: Protozoan mitochondrial tRNAs (mt-tRNAs) are repaired by a process known as 5'-editing. Mt-tRNA sequencing revealed organism-specific patterns of editing G-U base pairs, wherein some species remove G-U base pairs during 5'-editing, while others retain G-U pairs in the edited tRNA. We tested whether 3'-5' polymerases that catalyze the repair step of 5'-editing exhibit organism-specific preferences that explain the treatment of G-U base pairs. Biochemical and kinetic approaches revealed that a 3'-5' polymerase from Acanthamoeba castellanii tolerates G-U wobble pairs in editing substrates much more readily than several other enzymes, consistent with its biological pattern of editing.

SUBMITTER: Long Y

PROVIDER: S-EPMC4524524 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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In vitro substrate specificities of 3'-5' polymerases correlate with biological outcomes of tRNA 5'-editing reactions.

Long Yicheng Y Long Yicheng Y Jackman Jane E JE

FEBS letters 20150702 16

Protozoan mitochondrial tRNAs (mt-tRNAs) are repaired by a process known as 5'-editing. Mt-tRNA sequencing revealed organism-specific patterns of editing G-U base pairs, wherein some species remove G-U base pairs during 5'-editing, while others retain G-U pairs in the edited tRNA. We tested whether 3'-5' polymerases that catalyze the repair step of 5'-editing exhibit organism-specific preferences that explain the treatment of G-U base pairs. Biochemical and kinetic approaches revealed that a 3'- ...[more]

PMID: 26143376

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