Molecular Cloning and Expression Analysis of 13 MADS-Box Genes in Betula platyphylla

MADS-box genes encode a family of transcription factors that control a diverse range of processes in flowering plants. In this study, 13 unique MADS genes were cloned from Betula platyphylla Suk., and 2-year-old Betula seedlings propagated in glasshouses were selected as plant materials. The expression profile of each BpMADS was investigated during the growth season and following gibberellin (GA) treatments by real-time quantitative reverse transcription polymerase chain reaction. The relative abundance of the 13 BpMADS was shown to differ during each month, indicating that the activity of the genes varies during the annual growing period. Expression analyses demonstrated that these BpMADS were regulated by GA signaling pathways. Furthermore, the variations in expression patterns suggest that the genes act independently to fulfill specific functions or act cooperatively in physiological processes. The study of birch MADSs is important for the purposes of improving breeding techniques and molecular biotechnology.