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The role of PLTs during root meristem development requires its concentration gradient, which is not only contributed by posttranslational regulation such as growth dilution and intercellular movement, but likely also by finetuned transcriptional regulation for which not much has been known. Xiong et al. (pages 3812–3824) report that Arabidopsis JANUS positively regulates PLT1 expression in the root meristem by recruiting RNA polymerase II (Pol II) on PLT1 and by interacting with PLT1. JANUS-dependent recruitment of Pol II is inhibited through competitive binding of JANUS by GRF-INTERACTING FACTOR1/ANGUSTIFOLIA3 (GIF1/AN3), a transcriptional co-factor negatively regulating PLT1 expression. Finally, GIF1 and JANUS, the antagonistic regulators of PLT1, both depend on Arabidopsis IMPORTIN β4 (IMB4) for their nuclear accumulation. From top to bottom: the expression pattern of IMB4, JANUS, PLT1, and PLT1 in pseudocolors reflecting signal intensity.