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bioRxiv · 10.1101/2022.01.24.477497

The m6A writer FIONA1 methylates the 3'UTR of FLC and controls flowering in Arabidopsis

Sun, B.·Bhati, K. K.·Edwards, A. K.·Petri, L.·Kruusvee, V.·Blaakmeer, A.·Dolde, U.·Rodrigues, V.·Straub, D.·Wenkel, S.
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Abstract

Adenosine bases of RNA can be transiently modified by the deposition of a methyl-group to form N6-methyladenosine (m6A). This adenosine-methylation is an ancient process and the enzymes involved are evolutionary highly conserved. A genetic screen designed to identified suppressors of late flowering transgenic Arabidopsis plants overexpressing the miP1a microProtein yielded a new allele of the FIONA1 (FIO1) m6A-methyltransferase. To characterize the early flowering phenotype of fio1 mutant plants we employed an integrative approach of mRNA-seq, Nanopore direct RNA-sequencing and meRIP-seq to identify differentially expressed transcripts as well as differentially methylated mRNAs. We provide evidence that FIO1 is the elusive methylase responsible for the 3-end methylation of the FLOWERING LOCUS C (FLC) transcript. Furthermore, our genetic and biochemical data suggest that 3-methylation stabilizes FLC mRNAs and non-methylated FLC is a target for rapid degradation.

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Sun, B., Bhati, K. K., Edwards, A. K., Petri, L., Kruusvee, V., Blaakmeer, A., Dolde, U., Rodrigues, V., Straub, D., Wenkel, S.. 2022-01-25. The m6A writer FIONA1 methylates the 3'UTR of FLC and controls flowering in Arabidopsis. https://doi.org/10.1101/2022.01.24.477497

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