Genome-Wide High Resolution Expression Map and Functions of Key Cell Fate Determinants Reveal the Dynamics of Crown Root Development in Rice

Root architecture is a major determinant of plant productivity. Adventitious/crown roots (CRs) developing from non-root tissues shape up the root architecture in rice. Mechanisms underlying initiation and subsequent outgrowth of CR primordia (CRP) remain under explored. Here, we provide genome-wide dynamics of gene expression patterns at distinct developmental stages of CRP formation. Our analyses reveal that early regulated transcription of potential epigenetic modifiers, key transcription factors and cell division regulators prime the initiation of CRP followed by progressive activation of auxin signaling modules ensure their outgrowth. In depth analysis of spatio-temporal expression patterns of key cell fate determinants and the functional analyses of rice () and () genes reveal their unprecedented role in CRP development. Our study suggests that activates and expression during CRP initiation and expression to accomplish their outgrowth. Interestingly, genes, when expressed in the transcriptional domain of root-borne lateral root primordia of mutant, rescued their outgrowth demonstrating the conserved role of genes in root primordia outgrowth irrespective of their developmental origin. Together, these findings unveil the molecular framework of cellular reprogramming during trans-differentiation of shoot tissue to root leading to culmination of robust root architecture in monocot species which got evolutionary diverged from dicots.