mRNA adenosine methylase (MTA) deposits m <sup>6</sup> A on pri-miRNAs to modulate miRNA biogenesis in <i>Arabidopsis thaliana</i>
Susheel Sagar Bhat, Dawid Bielewicz, Tomasz Gulanicz, Zsuzsanna Bódi, Xiang Yu, Stephen J. Anderson, Łukasz Szewc, Mateusz Bajczyk, Jakub Dolata, Natalia Grzelak, Dariusz Jan Smoliński, Brian D. Gregory, Rupert G. Fray, Artur Jarmołowski, Zofia Szweykowska-Kulińska
Abstract
Significance Recently N 6 -methyladenosine (m 6 A) methylation has emerged as a biological process with significant impact on cellular functions. However, almost all the research regarding m 6 A methylation has been based on mRNAs. In our research, we focus on how m 6 A methylation affects microRNA (miRNA) biogenesis in Arabidopsis . In brief, we show that m 6 A methylation is necessary to maintain proper levels of mature miRNAs as well as their precursors. m 6 A mark affects pri-miRNA secondary structures and affects the recruitment of the Microprocessor to pri-miRNAs. We also demonstrate the interactions of MTA (m 6 A writer) with other proteins involved in miRNA biogenesis, namely RNA Polymerase II and TOUGH. Our study provides evidence of the role played by m 6 A in plant miRNA biogenesis.