关键词: 牡丹, 种子, ABA含量, PobZIP1, 半定量RT-PCR

Abstract: One important transcription factor gene PobZIP1 involved in ABA signaling was obtained by RT-PCR，first time in Paeonia ostii‘Fengdan’. And the abscisic acid（ABA）content in seeds of ‘Fengdan’from different developmental stages was analyzed by ultra-performance liquid chromatography/ tandem mass spectrometric（UPLC-MS/MS）method. The full length of the coding sequence of PobZIP1 was 957 bp，encoding a protein of 318 amino acid residues with a characteristic bZIP domain in the C-terminal domain. The GenBank accession number is KJ009392. A phylogenetic analysis with otherbZIP proteins from Arabidopsis thaliana revealed that PobZIP1 belongs to the group A of bZIP transcription factors，and it was closely related to AtbZIP39/ABI5. Then another phylogenetic tree was constructed with other bZIPs from different species，the results suggested that PobZIP1 be closely related to bZIP protein in Malus × domestica. Specific tissue and organ expression analysis showed that PobZIP1 could express in leaves，stems，roots and buds，while low expression in buds. The PobZIP1 expression pattern of different developmental stages of seeds was up-down trend. The results suggested that ABA content increased rapidly in early developmental stages of seeds，then decreased and kept relatively high level. It has been hypothesized that the high level of ABA and PobZIP1 in late developmental stages could induce seeds to dormancy.

Key words: tree peony, seed, ABA content, PobZIP1, semi-quantitative RT-PCR