Zhou Wen, Lu Qingtao, Li Qingwei, Wang Lei, Ding Shunhua, Zhang Aihong, Wen Xiaogang, Zhang Lixin, Lu Congming
Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Proc Natl Acad Sci U S A. 2017 Feb 21;114(8):E1554-E1563. doi: 10.1073/pnas.1612460114. Epub 2017 Feb 6.
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 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.
人们已经进行了大量尝试来鉴定和改造序列特异性RNA内切核酸酶，因为这些酶将有助于高效地操纵RNA。然而，迄今为止，尚未发现以序列特异性方式识别RNA的天然RNA内切核酸酶。在此，我们报告称，具有小MutS相关（SMR）结构域的五肽重复序列（PPR）蛋白类囊体形成抑制因子1（SOT1）具有RNA内切核酸酶活性。我们表明，SOT1的SMR部分通过PPR结构域对23S和4.5S rRNA进行内切核酸成熟，特异性识别叶绿体23S-4.5S rRNA前体5'端的一个13个核苷酸的RNA序列。此外，我们成功改造了具有改变的PPR基序的SOT1蛋白，使其能够识别并切割预测的RNA底物。我们的研究结果表明SOT1是一种用于RNA操纵的令人兴奋的工具。
