AGO6 functions in RNA-mediated transcriptional gene silencing in shoot and root meristems in Arabidopsis thaliana

• Published in: PloS one 2011-10, Vol.6 (10), p.e25730-e25730
• Main Authors: Eun, Changho, Lorkovic, Zdravko J, Naumann, Ulf, Long, Quan, Havecker, Ericka R, Simon, Stacey A, Meyers, Blake C, Matzke, Antonius J M, Matzke, Marjori
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - chemistry; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Argonaute Proteins - chemistry; Argonaute Proteins - genetics; Argonaute Proteins - metabolism; Base Sequence; Bioinformatics; Biology; Biosynthesis; Caenorhabditis elegans; Chromatin; Chromatin remodeling; Deoxyribonucleic acid; DNA; DNA binding proteins; DNA methylation; DNA Methylation - genetics; DNA polymerases; Epigenetic inheritance; Gene Expression Regulation, Plant - genetics; Gene sequencing; Gene Silencing; Genetic aspects; Genetic engineering; Genetic screening; Genetic testing; Homology; Industrial plants; Meristem - genetics; Meristem - metabolism; Meristems; Methylation; Molecular Sequence Data; Mutants; Nematodes; Physics; Plant Roots - genetics; Plant Roots - metabolism; Promoter Regions, Genetic - genetics; Promoters (Genetics); Protein binding; Proteins; Ribonucleic acid; RNA; RNA modification; RNA polymerase; RNA polymerases; RNA, Plant - genetics; RNA-mediated interference; Seeds; siRNA; Soil sciences; Transcription (Genetics); Transcription factors; Transcription, Genetic - genetics; Transgenes - genetics; Transposons
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0025730

RNA-directed DNA methylation (RdDM) is a small interfering RNA (siRNA)-mediated epigenetic modification that contributes to transposon silencing in plants. RdDM requires a complex transcriptional machinery that includes specialized RNA polymerases, named Pol IV and Pol V, as well as chromatin remodelling proteins, transcription factors, RNA binding proteins, and other plant-specific proteins whose functions are not yet clarified. In Arabidopsis thaliana, DICER-LIKE3 and members of the ARGONAUTE4 group of ARGONAUTE (AGO) proteins are involved, respectively, in generating and using 24-nt siRNAs that trigger methylation and transcriptional gene silencing of homologous promoter sequences. AGO4 is the main AGO protein implicated in the RdDM pathway. Here we report the identification of the related AGO6 in a forward genetic screen for mutants defective in RdDM and transcriptional gene silencing in shoot and root apical meristems in Arabidopsis thaliana. The identification of AGO6, and not AGO4, in our screen is consistent with the primary expression of AGO6 in shoot and root growing points.