Nonsense-mediated mRNA decay modulates Arabidopsis flowering time via the SET DOMAIN GROUP 40-FLOWERING LOCUS C module.

The nonsense-mediated mRNA decay (NMD) surveillance system clears aberrant mRNAs from the cell, thus preventing the accumulation of truncated proteins. Although loss of the core NMD proteins UP-FRAMESHIFT1 (UPF1) and UPF3 leads to late flowering in Arabidopsis, the underlying mechanism remains elusive. Here, we showed that mutations in UPF1 and UPF3 cause temperature- and photoperiod-independent late flowering.