研究基础：The role of PLTs during root meristem development requires a concentration gradient, which is not only contributed by post-translational regulation such as growth dilution and intercellular movement, but also likely by a largely unknown fine-tuned transcriptional regulatory mechanism.

结果1-JANUS正向调控PLT1：We report here that Arabidopsis JANUS positively regulates PLT1 expression in the root meristem by recruiting RNA polymerase II (Pol II) to PLT1 and by interacting with PLT1.

结果2-GIF1负向调控PLT1：JANUS-dependent recruitment of Pol II is inhibited through the competitive binding of JANUS by GRF-INTERACTING FACTOR1/ANGUSTIFOLIA3 (GIF1/AN3), a transcriptional co-factor that negatively regulates PLT1 expression.

结果3-输入蛋白：Finally, GIF1 and JANUS, the antagonistic regulators of PLT1, both depend on Arabidopsis IMPORTIN β4 (IMB4) for their nuclear accumulation.

结论：The combination of an importin and its two antagonistic cargos in PLT1 transcription may have logistic benefits in fine-tuning the transcription of PLT1 in root meristem.