Cloning and characterization of two cDNAs encoding rice MADS box protein

To elucidate the relationship between MADS box gene and rice morphogenesis, RT-PCR with MADS domain specific primers was performed to isolate MADS box gene from young panicle of rice Two cD-NAs, designated as nmadsl and nmadsS, displayed the structure of a typical plant MADS box gene which consists of the MADS domain, I region, K domain, and C-terminal region. Based on sequence homology, nmadsl is classified as a member of GLO subfamily, and nmadsS belongs to AGL2 subfamily. Hybridization analysis revealed that nmadsl and nmads3 were preferentially expressed in rice redifferentiated callus and young panicles but were not in rice seedling. An additional transcript of nmadsl was also found in young panicle of cytoplasmic male-sterile line Zhenshan 97A but was not in its maintenance line Zhanshan 97B.