AtHAP5A regulates iron translocation in iron‐deficient Arabidopsis thaliana. Issue 12 (20th July 2020)

• Record Type: Journal Article
• Authors: Zhu, Xiao Fang; Wu, Qi; Meng, Yu Ting; Tao, Ye; Shen, Ren Fang
• Is Part Of: Journal of integrative plant biology. Volume 62:Issue 12(2020)
• Page Start: 1910
• Page End: 1925
• Publication Date: 2020-07-20
• Subjects: Arabidopsis -- bioavailability -- chlorosis -- micronutrient -- nicotianamine synthase 1 -- transcription factor (TF); Plants -- Periodicals; Plants -- China -- Periodicals; Electronic journals; 580.5
• DOI: 10.1111/jipb.12984
• Languages: English
• ISSNs: 1672-9072

Abstract

Abstract: Iron (Fe) deficient plants employ multiple strategies to increase root uptake and root‐to‐shoot translocation of Fe. The identification of genes that are responsible for these processes, and a comprehensive understanding of the regulatory effects of transcriptional networks on their expression, including transcription factors (TFs), is underway in Arabidopsis thaliana . Here, we show that a Histone‐ or heme‐associated proteins (HAP) transcription factor (TF), HAP5A, is necessary for the response to Fe deficiency in Arabidopsis . Its expression was induced under Fe deficiency, and the lack of HAP5A significantly decreased Fe translocation from the root to the shoot, resulting in substantial chlorosis of the newly expanded leaves, compared with the wild‐type (WT, Col‐0). Further analysis found that the expression of a gene encoding nicotianamine (NA) synthase ( NAS1 ) was dramatically decreased in the hap5a mutant, regardless of the Fe status. Yeast‐one‐hybrid and ChIP analyses suggested that HAP5A directly binds to the promoter region of NAS1 . Moreover, overexpression of NAS1 could rescue the chlorosis phenotype of hap5a in Fe deficient conditions. In summary, a novel pathway was elucidated, showing that NAS1‐dependent translocation of Fe from the root to the shoot is controlled by HAP5A in Fe‐deficient Arabidopsis thaliana . Abstract : The Arabidopsis heme‐associated protein (HAP) transcription factor HAP5A modulates Fe‐deficiency responses by binding to the promoter of NICOTIANAMINE SYNTHASE1 (NAS1) and increasing NAS1 expression. NAS1 mediates root‐to‐shoot translocation of iron and thus, the increased NAS1 expression improves growth of Arabidopsis under iron‐deficient conditions.