分析了F-box基因FOA1(F-box overexpressed/oppressed ABA signaling)在拟南芥不同组织器官的表达模式,以及ABA和NaCl对其表达的调节.结果发现,FOA1在根和花中表达较高茎中表达较低;外源ABA和NaCl处理能迅速诱导FOA1基因的表达.分析ABA处理条件下,过量表达株系FOA1ox1,FOA1ox2和T-DNA插入突变体foa1的表型发现,突变体foa1的种子萌发率下降、根较短、气孔开度较大、脯氨酸积累增加,且对外源ABA敏感;过量表达株系的表型则相反,对ABA的敏感性降低.ABA处理条件下,一系列ABA信号转导转录因子在foa1突变体中的转录水平比野生型高,而ABA及胁迫应答基因在foa1突变体中的转录水平则比野生型低.这些研究结果表明,FOA1是ABA信号通路相关基因,并可能起负调控作用.
The expression of FOA1(F-box overexpressed/oppressed ABA signaling) in different organs of Arabidopsis,and in response to ABA and NaCl,was analyzed.The expression level of FOA1 is higher in the root and is lower in the stem,and is induced rapidly by ABA and NaCl.The phenotypes of T-DNA insertion mutant foa1 and FOA1 overexpression lines FOA1ox1 and FOA1ox2 were analyzed.The foa1 mutant exhibited a lower germination rate,shorter root length,more stomatal opening,increased proline accumulation and hypersensitivity to ABA compared with the wild type.In contrast,the overexpression lines showed lower sensitivity to ABA than the wild type.The expression levels of several ABA and stress-responsive transcription factors and genes were altered in the foa1 mutant in response to ABA.Compared with the wild type,the expression levels of ABA-responsive transcription factors were higher,but ABA and stress-responsive genes were lower in foa1 mutant.This study demonstrates that FOA1 is an ABA signaling-related gene,and may play a negative role in ABA signaling.
