摘要
Ribosomal RNAs(rRNAs) provide the structural framework of ribosomes and play critical roles in protein translation.In ribosome biogenesis,rRNAs acquire various modifications that can influence the structure and catalytic activity of ribosomes.However,rRNA modifications in plants have yet to be fully defined.Herein,we proposed a method to purify rRNAs by a successive isolation with different strategies,including poly A-based m RNA depletion and agarose gel electrophoresis-based purification,with which highly pure rRNAs could be obtained.In addition,we developed a liquid chromatography-electrospray ionization-tandem mass spectrometry(LC-ESI-MS/MS) method to systematically profile and characterize modifications from the isolated highly pure plant 18S rRNA and 25S rRNA.LC-ESI-MS/MS analysis showed that 10 and 12 kinds of modifications were present in plant 18S rRNA and 25S rRNA,respectively.Notably,among these identified modifications,2 kinds of modifications of N^(2),N^(2)-dimethylguanosine(m^(2,2)G)and N^(6),N^(6)-dimethyladenosine(m^(6,6)A) in 18S rRNA,and 4 kinds of modifications of m^(2,2)G,m^(6,6)A,N7-methylguanosine(m^(7)G) and 3-methyluridin(m^(3)U) in 25S rRNA,were first reported to be present in plants.Moreover,exposure of Arabidopsis thaliana to cadmium(Cd) led to significant changes of modifications in both 18S rRNA and 25S rRNA of plants,indicating that rRNA modifications play important roles in response to environmental stress.The discovery of new modifications in plant rRNAs improves the spectra of plant rRNA modifications and may promote the investigation of the functional roles of plant ribosomes in regulating gene expression.
基金
supported by the Fundamental Research Funds for the Central Universities(No.2042021kf0212)
the National Natural Science Foundation of China(Nos.22074110 and 21721005)。
作者简介
Corresponding author at:Bi-Feng Yuan,Sauvage Center for Molecular Sciences,Department of Chemistry,Wuhan University,Wuhan 430072,China.E-mail address:bfyuan@whu.edu.cn。
