Tolerance of submergence in rice: gene studies using differential display technique

Gene expression profiles between submergence rice ( Oryza sativa ssp. indica ) varieties, tolerant FR13A and sensitive IR39595-503-2-1-2, under submergence stress were identified using differential display reverse transcriptase-polymerase chain reaction (DDRT-PCR). A total of 1428 bands were amplified with 40 pairs of primers, of which 102 were significantly different between the two lines. The differential display ratio was 7.1%. Among 42 differential display bands derived from the submergence tolerant variety, the expression of seven fragments was confirmed by Northern blot analysis. The analysis of their sequences indicated that four of them showed high homology with genes related to a water stress response: genes encoding ATP-binding protein, isocitrate dehydrogenase, NADH dehydrogenase and terminal acetyltransferase, respectively. The remaining three fragments were novel cDNA fragments.