Flowering plant genomes encode four or five DICER-LIKE (DCL) enzymes that produce small interfering RNAs (siRNAs) and microRNAs, which function in RNA interference (RNAi). Different RNAi pathways in plants effect transposon silencing, antiviral defense, and endogenous gene regulation. DCL2 acts genetically redundantly with DCL4 to confer basal antiviral defense.
View Article and Find Full Text PDFOver 70% of vascular flowering plants engage in endosymbiotic associations with arbuscular mycorrhizal (AM) fungi. VAPYRIN (VPY) is a plant protein that is required for intracellular accommodation of AM fungi but how it functions is still unclear. VPY has a large ankyrin repeat domain with potential for interactions with multiple proteins.
View Article and Find Full Text PDFThe Arabidopsis genome encodes ten Argonautes proteins showing distinct expression pattern as well as intracellular localisation during sexual reproduction.
View Article and Find Full Text PDFArabidopsis encodes 10 ARGONAUTE (AGO) effectors of RNA silencing, canonically loaded with either 21-22 nucleotide (nt) long small RNAs (sRNAs) to mediate post-transcriptional gene silencing (PTGS) or 24 nt 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 patterns differ drastically, with AGO2 being expressed in both male and female gametes whereas AGO3 accumulates in aerial vascular terminations and specifically in chalazal seed integuments.
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