BioProject

Plant phasiRNAs contribute to robust male fertility, however, specific functions remain undefined. More...

Plant phasiRNAs contribute to robust male fertility, however, specific functions remain undefined. male sterile23 (ms23), necessary for both 24-nt phasiRNA precursor (24-PHAS) loci and Dicer-like5 (Dcl5) expression, or dcl5-1 mutants unable to slice PHAS transcripts, lack nearly all 24-nt phasiRNAs. Based on capture sequence bisulfite sequencing, we find that CHH DNA methylation of most 24-PHAS loci is identical in control and mutant anthers prior to PHAS transcriptional activation. However, increased CHH methylation that is present in fertile anthers expressing 24-PHAS is absent in these mutants. Since dcl5-1 anthers express PHAS precursors, we conclude that the 24-nt phasiRNAs, but not the activation of PHAS transcription is required for targeting CHH methylation to these loci. Although PHAS precursors are processed into multiple 24-nt phasiRNA products, there is dramatic differential product accumulation. Higher CHH methylation is correlated with 24-nt phasiRNA abundance within individual loci, reinforcing the conclusion that 24-nt phasiRNAs contribute to increased CHH methylation at complementary sites. Less...