Abstract text: In plants, cytokinesis differs from animal cells, as the de novo formation of the cell plate develops into the new cell wall, partitioning the cytoplasm of the dividing cell. While cytokinin is well known for its role in inducing organogenesis, the mechanisms by which it regulates cell division, particularly cytokinesis, remain largely unknown.

Here we show that inhibition of cytokinin signaling disrupts plant cytokinesis. Interference with a specific Arabidopsis cytokinin receptor, using a chemical biology approach, alters cytokinin signaling and results in arrested cell plate formation. Biochemical and computational assays demonstrate a direct association between the inhibitor and the receptor, while the receptor's localization at the forming cell plate supports its functional role during cytokinesis. Moreover, loss-of-function mutations in specific downstream response regulators abolish polysaccharide deposition at the cell plate, revealing a cytokinin-dependent mechanism that governs cell plate maturation.

Together, these findings establish specific receptor-mediated cytokinin signaling as a key regulator of root cell division and cell plate maturation, linking upstream hormonal perception to the final cytokinetic machinery. Our findings provide an innovative understanding of how hormonal signaling controls cell wall assembly and division, with broad implications for diverse plant species.