Figure 2.

Analysis of source-to-sink amino acid transport in two AAP1-OE lines (AAP1-OE1 and AAP1-OE2) and wild-type (WT) pea plants. Eight-week-old plants grown under low (2 g of N per week), moderate (4 g of N per week), or high N (8 g of N per week) supply were examined. A, Expression analysis of the amino acid transporters AAP1 (Zhang et al., 2010) and CAT6 (Tan et al., 2010) in source leaves using reverse transcription-quantitative PCR. Results are shown as fold change compared with the wild type (n = 5 biological replicates). A mean fold change of greater than 2 between the wild type and mutants was used to identify differentially expressed genes. B, Total amino acids in leaf exudates (n ≥ 7). C, Individual amino acids (AA) in leaf exudates (n ≥ 7). Data are means ± sd. Significant differences for each AAP1-OE line are indicated by letters (A and B) or asterisks (C; ANOVA; P ≤ 0.05).