EN
MicroRNA-mediated regulation of target genes is critical for development and adaptation. A handful of plant miRNAs along with the targets are conserved across highly diverged species. In most cases, these conserved targets are DNA-binding transcription factors that play important roles in plant development. Events of polyploidy that generate paralogs can open opportunities for generation of novel regulatory modules. The present study was performed to investigate syntenic relationship at loci surrounding miR165 between A. thaliana and B. rapa, a meso-polyploid, and identify paralogs if any. In silico comparative sequence analysis of genomic regions between A. thaliana and B. rapa reveals substantial synteny and micro-collinearity, albeit with several instances of insertions/deletions. Overexpression of miR165a recapitulates the phenotypes caused by drastic reduction in the expression level of HD-ZIP III members (REV and PHV). Constitutively overexpressed miR165a lines of B. juncea and A. thaliana show altered flower development along with the impaired vegetative growth. The present findings are thus in agreement with the known roles of miR165a in mediating plant growth and development implying evolutionary conservation.