Activities of Phenylalanine- and Tyrosine-Ammonia Lyases and Aminotransferases during Organogenesis in Callus Cultures of Rice

Activities of key enzymes involved in the shikimic acid pathway,namely, phenylalanine ammonia-lyase, tyrosine ammonia-lyase,phenylalanine aminotransferase and tyrosine aminotransferase,were examined during initiation of roots and shoots in calluscultures of rice. Enhancement of the activities of tyrosine-ammonialyase and tyrosine aminotransferase but not of phenylalanine-ammonialyase and phenylalanine aminotransferase was observed in organ-formingcultures, as compared to activities of these enzymes in non-organ-formingcultures. The role of these enzymes in such organogenetic processesis discussed (Received March 16, 1988; Accepted October 19, 1988)