DOI: 10.1101/500769Dec 18, 2018Paper

Functional characterization of Arabidopsis ARGONAUTE 3 in reproductive tissue

BioRxiv : the Preprint Server for Biology
Pauline E JullienOlivier Voinnet


Arabidopsis encodes ten ARGONAUTE (AGO) effectors of RNA silencing, canonically loaded with either 21-22nt small RNAs (sRNA) to mediate post-transcriptional-gene- silencing (PTGS) or 24nt sRNAs to promote RNA-directed-DNA-methylation. Using full- locus constructs, we characterized the expression, biochemical properties, and possible modes of action of AGO3. Although AGO3 arose from a recent duplication at the AGO2 locus, their expression differs drastically, with AGO2 being expressed in both male and female gametes whereas AGO3 accumulates in aerial vascular terminations and specifically in chalazal seed integuments. Accordingly, AGO3 down-regulation alters gene expression in siliques. Similar to AGO2, AGO3 binds sRNAs with a strong 5'-adenosine bias, but unlike most Arabidopsis AGOs - AGO2 included - it binds efficiently both 24nt and 21nt sRNAs. AGO3 immunoprecipitation experiments in siliques revealed that these sRNAs mostly correspond to genes and intergenic regions in a manner reflecting their respective accumulation from their loci-of-origin. AGO3 localizes to the cytoplasm and co-fractionates with polysomes to possibly mediate PTGS via translation inhibition.

Related Concepts

Gene Duplication
Gene Expression
Small Nuclear RNA
Arabidopsis thaliana <plant>
Binding Protein

Related Feeds

BioRxiv & MedRxiv Preprints

BioRxiv and MedRxiv are the preprint servers for biology and health sciences respectively, operated by Cold Spring Harbor Laboratory. Here are the latest preprint articles (which are not peer-reviewed) from BioRxiv and MedRxiv.