Extended Data Fig. 3: MtDELLA1 is mobile in Medicago and Arabidopsis roots.

a–f, Transgenic roots of Medicago. All scale bars, 50 µm. a-b, pAtSCR::GFP–GUS activity in the endodermis of transformed M. truncatula ecotype A17 root. (a) GFP channel. (b) Overlay of GFP channel and bright field channel. en, endodermis. c, Confocal image of pAtSCR:MtDELLA1-∆18–GFP transformed M. truncatula ecotype A17 root. d, Confocal image of pAtSCR::MtDELLA1-∆18–GFP transformed M. truncatula della1della2 root inoculated with R. irregularis for four weeks. The arrowhead indicates arbuscule. e, f, Confocal image of pAtSCR::MtDELLA1-∆18–GFP transformed M. truncatula ecotype A17 root inoculated with rhizobium strain S. meliloti 2011 for three weeks. (e) GFP channel. (f) Overlay of GFP channel and bright field channel. Fluorescence from MtDELLA1-∆18–GFP was observed in multiple cortex layers. All the experiments were repeated more than twice with similar results. g-j, Transgenic roots of Arabidopsis. All scale bars, 25 µm. (g and i) pAtSCR::GFP-GUS activity in Arabidopsis mature root (g) and root tip (i) after 5 DAG (days after germination). (h and j) Expression of pAtSCR::MtDELLA1-∆18–GFP in Arabidopsis mature root (h) and root tip (j). (h) Arabidopsis roots were counterstained with propidium iodide (PI). (g, i and j) Arabidopsis roots were treated with Clearsee solution for one week and cell walls stained with calcofluor white (purple). Each result represents eight independent transformation lines. Arrow indicate GFP signaling. ep, epidermis; co, cortex; en, endodermis.