| 摘要: |
| FIT是调控拟南芥铁稳态的一个关键调控因子,它在转录水平受到缺铁诱导，但是背后的调控机制还不甚清楚。该研究以拟南芥bHLH38和FIT的单、双过表达植物及bHLH Ib四突变体为研究材料，进行了缺铁处理实验，并通过定量PCR分析了FIT的转录水平。结果表明：（1）在铁充足时，bHLH38过表达植物中FIT的转录水平显著高于其在野生型中水平；（2）在bHLH Ib四突变体里FIT的转录水平不受缺铁诱导；（3）FIT单过表达不能激活内源FIT的转录，但bHLH38和FIT的双过表达则可以激活内源FIT的转录；（4）在缺铁条件下，所有植物中FIT的转录水平均与野生型中的FIT水平无明显差异。基于以上结果，该研究认为bHLH Ib转录因子是缺铁诱导FIT转录的必要条件，而非充分条件。 |
| 关键词: 铁，bHLH Ib，FIT，拟南芥 |
| DOI： |
| 分类号: |
| Fund project:云南省应用基础研究计划项目(2019FB028和202001AT070131) |
|
| bHLH Ib transcription factors regulate the transcription of FIT in Arabidopsis thaliana |
|
YANG Yujie, LIANG Gang
|
|
CASKey Laboratory of Tropical Plant Resources and Sustainable Use,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Kunming
|
| Abstract: |
| FIT (FER-LIKE IRON DEFICIENCY-INDUCED TRANSCRIPTION FACTOR) is a key regulator of Fe homeostasis, which is up-regulated under Fe deficiency conditions, however, the underlying mechanism is still unclear. In this study, the transcript levels of FIT was determined in the single and dual overexpression plants for bHLH38 and FIT, as well as the bHLH Ib quadruple mutant. Under Fe sufficient conditions, FIT increased in the bHLH38 overexpression plants compared with in the wild type plants. The transcription of FIT did not respond to Fe deficiency in the bHLH Ib quadruple mutant. The overexpression of FIT could not activate the transcription of native FIT, and the dual overexpression of FIT and bHLH38 promoted the transcription of native FIT under Fe sufficient conditions. There was no difference for the expression of FIT between the transgenic or mutant plants and wild type plants under Fe deficiency conditions. Taken together, these data suggest that bHLH Ib transcription factors are necessary, but not sufficient, for the upregulation of FIT by Fe deficiency. |
| Key words: Iron, bHLH Ib, FIT, Arabidopsis thaliana |
