Fig. 3: InDel1032 promotes shoot Na⁺ exclusion by decreasing the translation efficiency of ZmNSA1 mRNA.

a The association analysis of the genetic variations in ZmNSA1 with shoot Na⁺ contents among 166 maize inbred lines. Upper panel showed the characterization of variations significantly associated with shoot Na⁺ contents. The red dots highlighted InDel1032 and SNP1173 that showed the highest association. Lower panel displayed the pattern of pairwise LD of the variations, and the red dots highlight the complete LD between InDel1032 and SNP1173. b Left panel showed the haplotypes of ZmNSA1 grouped according to the significant variants. Right panel showed the distributions of shoot Na⁺ contents for each haplotype group. Statistical significance was determined by a two-sided t-test (n = 148 for Hap1; n = 18 for Hap2). c, d Comparison of the transcript (c) and protein (d) levels of ZmNSA1 between randomly selected Hap1 and Hap2 inbred lines under control and NaHCO₃ conditions. e, f The transcript (e) and protein (f) levels of ZmNSA1 in ZmNSA1^UFMu protoplasts transformed with pSUPER-ZmNSA1-3′UTR(Hap1) and pSUPER-ZmNSA1-3′UTR(Hap2) (see Materials and methods). The non-transformed protoplasts provided a control. g Carton displayed the wild type and mutant 3′UTR forms. h, i The transcript (h) and protein (i) levels of ZmNSA1 in ZmNSA1^UFMu protoplasts expressing pSUPER-ZmNSA1 with indicated 3′UTRs. In f, i, co-transformation of pSUPER-GFP and subsequent protein blot assay using GFP antibody provided a control of transformation efficiency. Analysis of actin provided loading controls in d, f, i. Data in c, e, h were means ± s.d. of three independent experiments. Source data underlying Figs. 3c–f, 3h, and 3i are provided as a Source Data file.