Figure 8.

Complementation of nramp1-1 phenotype by MtNramp1 under the regulation of a nodule-specific promoter. A, Expression of Medtr6g081400, a nodule-specific MATE transporter used as a promoter source for the complementation construct. Expression of MtUbiquitin carboxyl-terminal hydrolase was used as positive control (MtUb). B, Growth of representative plants. C, Close view of representative nodules of each M. truncatula line. D, Fresh weight of shoots and roots. Data are the mean ± se (n = 4 plants). E, Nodule number per plant; 100% = 4.25 nodules/plant. Data are the average ± se (n = 4 plants). F, Nitrogenase activity in 28-dpi nodules. Acetylene reduction was measured in duplicate from two sets of five pooled plants. Data are the mean ± se; 100% = 31.85 nmol ethylene h^–1 g^–1. NFR, Nitrogen-fertilized roots; DR, denodulated roots; Nod, nodules; NFS, nitrogen-fertilized shoots; NS, shoots from nodulated plants; WT, wild type. Bars = 1 cm (B) and 1 mm (C).