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DING, Y.

Publications and source records attributed to DING, Y..

2 recordsLinked to original sources

In vivo nuclear RNA structurome reveals RNA-structure regulation of mRNA processing in plants

mRNA processing is critical for gene expression. A challenge in regulating mRNA processing is how to recognize the actual mRNA processing sites, such as splice and polyadenylation sites, when the sequence content is insufficient for this purpose. Previous studies suggested that RNA structure affects mRNA processing. However, the regulatory role of RNA structure in mRNA processing remains unclear. Here, we performed in vivo selective 2-hydroxyl acylation analysed by primer extension (SHAPE) chemical profiling on Arabidopsis nuclear RNAs and generated the in vivo nuclear RNA structure landscape. We found that nuclear mRNAs fold differently from cytosolic mRNAs. Notably, we discovered a two-nucleotide single-stranded RNA structure feature upstream of 5 splice sites that is strongly associated with splicing and the selection of alternative 5 splice sites. Moreover, we found the single-strandedness of branch point is also associated with 3 splice site recognition. We also identified an RNA structure feature comprising two close-by single-stranded regions that is specifically associated with both polyadenylation and alternative polyadenylation events. Our work demonstrates an RNA structure regulatory mechanism for mRNA processing.

plant biology

RNA G-quadruplex structures exist and function in vivo

Guanine-rich sequences are able to form complex RNA structures termed RNA G-quadruplexes in vitro. Because of their high stability, RNA G-quadruplexes are proposed to exist in vivo and are suggested to be associated with important biological relevance. However, there is a lack of direct evidence for RNA G-quadruplex formation in living cells. Therefore, it is unclear whether any purported functions are associated with the specific sequence content or the formation of an RNA G-quadruplex structure. Here, we profiled the landscape of those guanine-rich regions with the in vitro folding potential in the Arabidopsis transcriptome. We found a global enrichment of RNA G-quadruplexes with two G-quartets whereby the folding potential is strongly influenced by RNA secondary structures. Using in vitro and in vivo RNA chemical structure profiling, we determined that hundreds of RNA G-quadruplex structures are strongly folded in both Arabidopsis and rice, providing direct evidence of RNA G-quadruplex formation in living eukaryotic cells. Subsequent genetic and biochemical analysis showed that RNA G-quadruplex folding was sufficient to regulate translation and modulate plant growth. Our study reveals the existence of RNA G-quadruplex in vivo, and indicates that RNA G-quadruplex structures act as important regulators of plant development and growth.

plant biology