RRC ID 74316
Author Liu W, Shoji K, Naganuma M, Tomari Y, Iwakawa HO.
Title The mechanisms of siRNA selection by plant Argonaute proteins triggering DNA methylation.
Journal Nucleic Acids Res
Abstract The model plant Arabidopsis thaliana encodes as many as ten Argonaute proteins (AGO1-10) with different functions. Each AGO selectively loads a set of small RNAs by recognizing their length and 5' nucleotide identity to properly regulate target genes. Previous studies showed that AGO4 and AGO6, key factors in DNA methylation, incorporate 24-nt small-interfering RNAs with 5' adenine (24A siRNAs). However, it has been unclear how these AGOs specifically load 24A siRNAs. Here, we biochemically investigated the siRNA preference of AGO4, AGO6 and their chimeric mutants. We found that AGO4 and AGO6 use distinct mechanisms to preferentially load 24A siRNAs. Moreover, we showed that the 5' A specificity of AGO4 and AGO6 is not determined by the previously known nucleotide specificity loop in the MID domain but rather by the coordination of the MID and PIWI domains. These findings advance our mechanistic understanding of how small RNAs are accurately sorted into different AGO proteins in plants.
Volume 50(22)
Pages 12997-13010
Published 2022-12-9
DOI 10.1093/nar/gkac1135
PII 6880726
PMID 36477368
PMC PMC9825178
MeSH Arabidopsis* / genetics Arabidopsis* / metabolism Arabidopsis Proteins* / genetics Arabidopsis Proteins* / metabolism Argonaute Proteins / genetics Argonaute Proteins / metabolism DNA Methylation / genetics Nucleotides / metabolism Plant Proteins / genetics RNA, Plant / genetics RNA, Plant / metabolism RNA, Small Interfering / genetics RNA, Small Interfering / metabolism
IF 11.502
Arabidopsis / Cultured plant cells, genes rpc00001