Fig. 2.

MVA-induced nuclear-associated Ca²⁺ spiking in legumes and nonlegumes. (A) Exogenous application of 100 µM MVA triggers Ca²⁺ spiking in M. truncatula root hair cells expressing YC3.6. (B) MVA restores Ca²⁺ spiking in roots silenced for HMGR1. (C) MVA induces nuclear Ca²⁺ spiking in atrichoblast cells of a M. truncatula root organ culture expressing nuclear-targeted YC2.1. (D) MVA-induced nuclear spiking in root hairs of L. japonicus expressing NLS-YC3.6. (E) Atrichoblasts of carrot root organ cultures expressing nuclear-targeted YC2.1 also respond to MVA. (F) In contrast, MVA does not elicit nuclear-associated Ca²⁺ spiking in trichoblast cells of Arabidopsis expressing YC3.6, which is unable to form endosymbiotic associations with either rhizobia or AM fungi.