Analysis of proteins from embryogenic and non-embryogenic rice (Oryza sativa L.) calli

When rice (Oryza sativa L.) embryos were cultured on Murashige-Skoog medium containing 2,4-dichlorophenoxyacetic acid and kinetin, both embryogenic (E) and non-embryogenic (NE) calli were formed. One and two-dimensional electrophoresis indicated that there were some qualititative differences between the proteins present in E and NE calli, and in rice embryos. Several E and NE-specific and embryo-specific polypeptides were evident. Two of the E-specific polypeptides of 54 and 24 kD corresponded to the major polypeptides in rice embryo extracts. One polypeptide of 22.7 kD was consistently present in the extracts from NE calli, but was present in much lower amounts in E calli, and was absent from embryo extracts. When E and NE calli were placed on regeneration medium for 12 days there were few changes in the polypeptide patterns of the two cell types, except for an increase in the amount of a 45 kD polypeptide in the NE calli.