Fig. 7.

Effect of salt stress on contents of proline and soluble sugars and gene expression in wild-type and transgenic rice plants. (A and B) Wild-type and transgenic rice seedlings of 14-d-old were exposed to 200 mM NaCl for 2 days and then collected for determination of proline (A) and soluble sugars (B) contents. (C–F) Expression levels of putative proline synthase genes (J033099M14 and J033031H21; C and D) and transporter genes (03g44230 and 07g01090; E–F) in transgenic and wild-type plants. Total RNA was extracted from the 14-d-old rice seedlings grown under control and salt stress (200 mM NaCl) conditions for 24 hours. The transcript levels were measured by real-time reverse-transcription PCR. Actin was used as an internal control. Data are mean±SE of three replicates. Asterisks indicate statistically significant differences (P < 0.05) between wild-type (WT) and transgenic lines (OE and Ri). The accession numbers of the sequences of J033099M14, J033031H21, 03g44230, and 07g01090 are AK102633, AK101230, AK067118, and AK0666298.