A repertoire of intronic lariat RNAs reveals tissue-specific regulation and target mimicry potential in plants  

作　　者：Yong Zhang Xiaotuo Zhang Qi Tang Lei Li Ting Jiang Yixiao Fang Hong Zhang Jixian Zhai Guodong Ren Binglian Zheng 

机构地区：[1]State Key Laboratory of Genetic Engineering,Institute of Plant Biology,School of Life Sciences,Fudan University,Shanghai 200438,China [2]Department of Biology,School of Life Sciences,Southern University of Science and Technology,Shenzhen 518055,China

出　　处：《Science China(Life Sciences)》2024年第6期1280-1291,共12页中国科学（生命科学英文版）

基　　金：supported by the National Natural Science Foundation of China(31830045,32025005,32100429)。

摘　　要：Lariat RNA is concomitantly produced by excised intron during RNA splicing,which is usually debranched by DBR1,an RNA debranching enzyme.However,increasing evidence showed that some lariat RNA could escape debranching.Little is known about how and why these lariat RNAs could be retained.By comparing the atlas of lariat RNAs between the non-dividing cell(mature pollen)and three actively dividing tissues(young shoot apex,young seeds,and young roots),we identified hundreds to thousands of lariat RNA naturally retained in each tissue,and the incidence of lariat RNA retention is much less in shoot apex while much more in pollen.Many lariat RNAs derived from the same intron or different lariat RNAs from the same pre-m RNA could be retained in one tissue while degraded in the other tissues.By deciphering lariat RNA sequences,we identified an AG-rich(RAAAAVAAAR)motif and a UC-rich(UCUCUYUCUC)motif for pollen-specific and the other three tissues-retained lariat RNAs,respectively.Reconstitution of the pollen-specific AG-rich motif indeed enhanced lariat RNA retention in plants.Biologically,hundreds of lariat RNAs harbored mi RNA binding sites,and dual-luciferase reporter assay showed that these natural lariat RNAs had the potential to protect expression of mi RNA target genes.Collectively,our results uncover that selective retention of lariat RNA is an actively regulatory process,and provide new insights into understanding how lariat RNA metabolism may impact mi RNA activity.

关 键 词：intron turnover lariat RNA miRNA RNA splicing DBR1 

分 类 号：Q943.2[生物学—植物学]