Expression of the ar-Amylase Gene RAmy3D in Rice (Oryza sativa L.) under Aerobic, Hypoxic and Anoxic Conditions

Abstract

Expression of the α-amylase gene RAmy3D was studied in aerobic, hypoxic, and anoxic conditions using the rice cuitivars Suweon 287 and Nipponbare by in situ hybridization. In the aerobic condition, the initial expression of RAmy3D in the scutellar epithelium and its later expression in the aleurone layer were consistent with the previous reports. However, hypoxia delayed the expression of RAmy3D in the scutellar epithelium, and blocked expression in the aleurone layer. In anoxia, RAmy3D expression in cv. Nipponbare was similar to that in hypoxia, but that in cv. Suweon 287 was significantly suppressed 4 d after seeding. These results suggest that the expression of the RAmy3D gene is also affected by anoxia. Considering the results of our previous report together, RAmy3D-encoded isoforms in anoxia may be mainly regulated at the post-transcriptional level. A possible process in the regulation of RAmy3D expression in germinating seeds is discussed.

Keywords

• ar-Amylase
• Gene expression
• Rice (Oryza sativa L.)