현사시나무 Gibberellic Acid-Stimulated Arabidopsis (GASA) 유전자의 발현 특성 및 건조 스트레스 내성 구명

Characterization of Gibberellic Acid-Stimulated Arabidopsis (GASA) gene to drought stress response in Poplar (Populus alba × P. glandulosa)

Gibberellic Acid-Stimulated Arabidopsis (GASA) genes are involved in plant hormone signaling, cell division and elongation, as well as in responses to stress conditions in plants. In this study, we isolated a GASA gene from hybrid poplar (Populus alba × P. glandulosa) and analyzed its physiological phenotype and molecular functions in poplar. PagGASA cDNA encodes a putative protein composed of 95 amino acids containing an N-terminal signal peptide and a conservative cysteine-rich C-terminal domain. Southern blot analysis revealed that one or two copies of the PagGASA are present in the poplar genome. The PagGASA transcripts were highly detected in flowers and roots. Moreover, the expression of PagGASA was induced by growth hormone (gibberellic acid) and stress hormones (abscisic acid, jasmonic acid, and salicylic acid). By using transgenic analysis, we showed that the upregulation of PagGASA in poplar provides high tolerance to drought stress. Therefore, our results suggest that PagGASA plays an important role in drought stress tolerance via stress-related plant hormone signaling in poplar.