Argonaute7 (AGO7) optimizes arbuscular mycorrhizal fungal associations and enhances competitive growth in Nicotiana attenuata.

Plants interact with arbuscular mycorrhizal fungi (AMF) and in doing so, change transcript levels of many miRNAs and their targets. However, the identity of an Argonaute (AGO) that modulates this interaction remains unknown, including in Nicotiana attenuata. We examined how the silencing of NaAGO1/2/4/7/and 10 by RNAi influenced plant-competitive ability under low-P conditions when they interact with AMF.

Distinguishing friends from foes: Can smRNAs modulate plant interactions with beneficial and pathogenic organisms?

In their agro-ecological habitats, plants are constantly challenged by fungal interactions that might be pathogenic or beneficial in nature, and thus, plants need to exhibit appropriate responses to discriminate between them. Such interactions involve sophisticated molecular mechanism of signal exchange, signal transduction and regulation of gene expression. Small RNAs (smRNAs), including the microRNAs (miRNAs), form an essential layer of regulation in plant developmental processes as well as in plant adaptation to environmental stresses, being key for the outcome during plant-microbial interactions.

microRNA390 modulates 's tolerance response to herbivory.

miR390 is a highly conserved miRNA in plant lineages known to function in growth and development processes, such as lateral root development, and in responses to salt and metal stress. In the ecological model species, , miR390's biological function remains unknown, which we explore here with a gain-of-function analysis with plants over-expressing (OE-) miR390 (Na-miR390) in glasshouse and natural environments. OEmiR390 plants showed normal developmental processes, including lateral root formation or reproductive output, in plants grown under standard conditions in the glasshouse.

Argonaute4 Modulates Resistance to Infection by Regulating Jasmonic Acid Signaling.

Argonautes (AGOs) associate with noncoding RNAs to regulate gene expression during development and stress adaptation. Their role in plant immunity against hemibiotrophic fungal infection remains poorly understood. Here, we explore the function of AGOs in the interaction of wild tobacco () with a naturally occurring hemibiotrophic pathogen, Among all AGOs, only transcripts of were elicited after fungal infection.

Argonaute 8 (AGO8) Mediates the Elicitation of Direct Defenses against Herbivory.

In , specific RNA-directed RNA polymerase (RdR1) and the Dicer-like (DCL3 and DCL4) proteins are recruited during herbivore attack to mediate the regulation of defense responses. However, the identity and role(s) of Argonautes (AGOs) involved in herbivory remain unknown. Of the 11 AGOs in the genome, we silenced the expression of 10.

Elucidation of defense-related signaling responses to spot blotch infection in bread wheat (Triticum aestivum L.).

Spot blotch disease, caused by Bipolaris sorokiniana, is an important threat to wheat, causing an annual loss of ~17%. Under epidemic conditions, these losses may be 100%, yet the molecular responses of wheat to spot blotch remain almost uncharacterized. Moreover, defense-related phytohormone signaling genes have been poorly characterized in wheat.