Fig. 1: NAD⁺ deficiency induced biosynthesis of glucosinolates (GSLs) in rosette leaves of qs-2.

a Integrated KEGG analysis of differentially expressed genes and accumulated compounds between Col-0 and qs-2 collectively indicate the significant induction of glucosinolate biosynthesis in qs-2. p values are calculated with the cumulative hypergeometric distribution by comparing the number of compounds in the set and in the background with a given annotation. Resulting p values are adjusted for multiple testing using the Benjamini–Hochberg adjusted p values method. Blue dots: upregulated genes (UP-DEGs); Orange dots: upregulated compounds detected in positive mode [(UP-DEcpds (M + H)⁺)]; Red dots: upregulated compounds detected in negative mode [(UP-DEcpds (M-H)⁻)]. Comparison of key aliphatic and indolic GSL contents (b) and GSL biosynthetic gene transcripts (c) in leaves of Col-0 and qs-2. Heatmaps indicate fold change in qs-2 vs. Col-0. Relative contents of indolic-GSLs I3M (d) and 4MOI3M (e), aliphatic-GSLs 4BTEY (f) and 4MSOB (g) determined in the rosette leaves of 21-day-old Col-0, qs-2, COM1 and COM2. Each bar represents the means ± SD (n = 6), and the significance analysis was performed by two-tailed Student’s t test. Relative contents of I3M (h), 4MOI3M (i), 4BTEY (j) and 4MSOB (k) in Col-0 and qs-2 with and without nicotinic acid (NA) treatment. Fourteen-day-old Col-0 and qs-2 mutant plants grown in soil were supplemented with 1 mM NA for additional 7 days before determination. The values represented the means ± SD (n = 6), two-sided Student’s t test. Source data are provided as a Source Data file.