Transcriptome analysis give insights into the role of miR394 in the regulation of flowering genes in Arabidopsis thaliana

BELÉN F.; BERNARDI Y.; ROSLI H.; POMBO M.; VEGETTI A.; DOTTO M.

Congreso; XXXIV Argentinian Meeting of Plant Physiology; 2023

Sociedad Argentina de Fisiología Vegetal

Understanding the intricate regulatory pathways governing plant development and flowering is essential for crop improvement and adaptation to changing environments. In this study, we investigated the role of microRNA miR394 in Arabidopsis thaliana by characterizing mir394a/mir394b double mutant plants. To explore transcriptomic changes associated with decreased expression of miR394, RNA-seq analysis was performed on 14-days-old wild-type (Col-0) and mir394a/mir394b double mutant plants. A total of 3826 differentially expressed genes (DEGs) were identified between the two genotypes. Closer examination of these DEGs revealed a significant impact on flowering-related genes. Notably, key genes involved in the establishment of inflorescence meristem and floral organ identity, including SOC1, FUL, AP1, AP3, AG, SEP3 and PI, exhibited increased expression in mir394a/mir394b double mutants plants, indicating that miR394 plays a key role in regulating the expression of flowering-related genes, influencing flowering time in Arabidopsis. These results are in line with those obtained by our group in previous studies, which highlighted that mir394a/mir394b double mutants displayed an early flowering phenotype. To gain insight into the spatiotemporal expression pattern of MIR394A and MIR394B genes, transgenic pMIR394A::GUS and pMIR394B::GUS Arabidopsis lines were generated. Our analysis revealed that both genes are expressed in diverse tissues, organs and developmental stages, including shoot apical meristem, leaf primordia, ovules and anthers, among others. These results highlight the dynamic and multifaceted expression pattern of MIR394A and MIR394B during plant growth and development, in accordance with several reports showing miR394 involvement in various processes. Overall, our findings contribute to the understanding of the regulatory network of miR394, controlling various aspects of plant development, shedding light on the regulation of flowering time in particular.