Confirmation of mutation sites by complementation or analysis of additional allelic mutants. A. Molecular basis of the EMS and insertion mutations. The mutation site in each gene is shown. Red triangle indicates T-DNA insertion site. B. Complementation of nis1 with the NIS1 genomic DNA construct. Plants were grown on medium containing 2.5 mM ammonium succinate for 3 days and transferred to the medium containing 5 mM KNO3 for 8 days. C. The allelic apg6-3 mutant shows similar small pale-green leaves as nis2. Plants were germinated on the 1% phyto-agar plates with 1/2 × MS and 1% sucrose for 12 days and then transferred to soil for 22 days. Photograph was taken at day 34 after germination. D. The allelic ncr1-2 mutant shares similar lateral root de-suppression phenotype as ncr1-1. Seedlings were geminated on medium containing 50 mM KNO3 for 14 days. Scale bar = 1 cm.