Molecular cloning and characterization of a rice gene encoding AP2/EREBP-type transcription factor and its expression in response to infection with blast fungus and abiotic stresses

The AP2/EREBP domain-containing transcription factors play various functions in developmental processes and stress-related responses in plants. In present study, a full-length cDNA OsEBP2 (Oryza sativa ethylene-responsive-element binding protein2), encoding a 396-amino-acid protein containing one AP2/EREBP domain, was isolated from a cDNA library prepared with japonica rice leaves infected by blast fungus Magnaporthe grisea, which is identity to the locus Os09g26420 and has been isolated from the japonica variety before. OsEBP2 is a member of Group VII of ERF family and is orthologous to OsBIERF1 in indica variety. OsEBP2 transcripts were detected at a similar level in the leaf, sheath and root of young Aichiasahi plants and in stem of 10-week-old plants. OsEBP2 expression was induced to increase more strongly in the compatible interaction between rice variety Aichiasahi and race 220 of M. grisea than in the incompatible one. OsEBP2 responded transiently to the treatments with MeJA, ABA and ethophen. In its promoter region several cis-elements involved in stress responses are present. Based on these results, we propose that the transcription factor encoded by gene OsEBP2 may be involved in rice defense response to infection by blast fungus and in stress response.