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PPR-SMR protein SOT1 has RNA endonuclease activity.

ABSTRACT: Numerous attempts have been made to identify and engineer sequence-specific RNA endonucleases, as these would allow for efficient RNA manipulation. However, no natural RNA endonuclease that recognizes RNA in a sequence-specific manner has been described to date. Here, we report that SUPPRESSOR OF THYLAKOID FORMATION 1 (SOT1), an Arabidopsis pentatricopeptide repeat (PPR) protein with a small MutS-related (SMR) domain, has RNA endonuclease activity. We show that the SMR moiety of SOT1 performs the endonucleolytic maturation of 23S and 4.5S rRNA through the PPR domain, specifically recognizing a 13-nucleotide RNA sequence in the 5' end of the chloroplast 23S-4.5S rRNA precursor. In addition, we successfully engineered the SOT1 protein with altered PPR motifs to recognize and cleave a predicted RNA substrate. Our findings point to SOT1 as an exciting tool for RNA manipulation.

SUBMITTER: Zhou W

PROVIDER: S-EPMC5338415 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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PPR-SMR protein SOT1 has RNA endonuclease activity.

Zhou Wen W Lu Qingtao Q Li Qingwei Q Wang Lei L Ding Shunhua S Zhang Aihong A Wen Xiaogang X Zhang Lixin L Lu Congming C

Proceedings of the National Academy of Sciences of the United States of America 20170206 8

Numerous attempts have been made to identify and engineer sequence-specific RNA endonucleases, as these would allow for efficient RNA manipulation. However, no natural RNA endonuclease that recognizes RNA in a sequence-specific manner has been described to date. Here, we report that SUPPRESSOR OF THYLAKOID FORMATION 1 (SOT1), an <i>Arabidopsis</i> pentatricopeptide repeat (PPR) protein with a small MutS-related (SMR) domain, has RNA endonuclease activity. We show that the SMR moiety of SOT1 perf ...[more]

PMID: 28167782

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