Cell layer specific and polysome associated RNA from Arabidopsis thaliana Col0 and hyl1 mutant roots.

microRNAs (miRNA’s) regulation target gene expression, often transcription factors and as such control entire transcriptional networks. This control is important for various developmental transitions and stress responses in a wide range of eukaryotic organisms. While miRNA-mediated gene regulation has been investigated over time (temporal) and in whole organs or tissues in multiple different organisms highlighting their importance, there has been a distinct lack of focus on spatial resolution of miRNA biology. Here we present at cell-type specific resolution, miRNA loading and miRNA action within the Arabidopsis root. Our results for the first time demonstrate the multiple novel modes of miRNA action and illustrate the widespread nature of miRNA movement, at a genome scale within a complex eukaryotic organ. 24 samples examined corresponding to HF-RPL18-IP for Col0 or hyl1 mutant plants expressing HF-RPL18 under 35S promoter or specific root cell layer promoter (columella/pACR4, stele/pSHR, endodermis/pSCR, cortex/pCO2 and epidermis/pWER) (2 replicates for each)