small RNA-seq of Arabidopsis pol2a mutants
DNA replication requires the faithful propagation of both genetic and epigenetic information. There is evidence that DNA polymerases play a role in transcriptional silencing, but the extent of their contribution and how it relates to heterochromatin maintenance is unclear. Analyzing a new hypomorphic pol2a mutant allele, we find that POL2A, the catalytic subunit of the DNA polymerase epsilon, maintains heterochromatin silencing and nuclear organization. We also found that POL2 inhibits DNA methylation and histone H3 lysine 9 methylation, which both correlate with 24-nucleotide small RNA accumulation. In this experiment, we sequenced small-RNA libraries generated from immature inflorescences of pol2a-10 and pol2a-12 mutants and wild-type plants.