Micro RNA biogenesis and movement in plant defense piming

LUCIANO MARTIN QUEVEDO; N. ALANIE; A. TENCHI; HERNÁN RAMIRO LASCANO; DAMIÁN ALEJANDRO CAMBIAGNO

Rosario

Congreso; RAFV Conference 2023. XXXIV Argentinian Meeting of Plant Physiology; 2023

Sociedad Argentina de Fisiología Vegetal

When plants encounter microorganisms, they activate defense responses to protect against pathogens or establish symbiotic relationships. Consequently, in most of cases, plants induce a phenomenon known as priming, characterized by an immunological memory that enables them to mount faster and stronger defenses upon subsequent exposures. Priming is characterized by a lack of constitutive defense activation, ensuring an efficient use of resources. This process can be activated either locally, at the site of initial microbe recognition, or systemically in non-infected tissues. At the core of this system, the expression of defense-response genes at both transcriptional and post-transcriptional levels plays a critical role. Micro RNAs (miRNAs) have emerged as major players in post-transcriptional gene silencing and activation of defense mechanisms. Our research focused on investigating the roles of two components of the miRNA biogenesis and systemic movement in the induction of systemic priming in Arabidopsis. We observed that both components are required for the proper induction of systemic priming. Furthermore, our investigations revealed the presence of specific miRNAs that could be involved in modulating systemic priming. Intriguingly, our results suggest that those components may regulate both their biogenesis/activity as well as their systemic mobilization during priming. We propose that following pathogen recognition, miRNA biogenesis and movement modulate the activation of the systemic priming, potentially serving as molecular signals for the establishment of the systemic priming. This research provides valuable insights into the underlying molecular mechanisms governing plant defense and contributes to our understanding of the dynamic and adaptive nature of priming in plant immunity.