Arabidopsis proteins with a transposon-related domain act in gene silencing

While screening for mutants in gene silencing, Ikeda et al. identified mail1, which shows elevated expression of transposable elements (TEs) and protein-coding genes, indicating that MAIL1 (MAINTENANCE OF MERISTEM-LIKE1) is required for epigenetic silencing of some genes. However, mail1 does not differ from wildtype in either DNA methylation or siRNA accumulation, indicating it is involved in a distinct form of gene silencing. DAPI staining showed that pericentromeric regions are decondensed in mail1. MAIL1 has an aminotransferase-like, plant mobile domain that is similar to a DNA-binding domain found in transposases. The function of this domain and whether it originated in a gene or a transposon remain unknown. Nature Comms. 10.1038/ncomms15122