Advances in the Regulation of Iron Homeostasis by bHLH Transcription Factors in Plant

doi:10.13560/j.cnki.biotech.bull.1985.2022-1474

Abstract

Abstract:

Iron is an essential micronutrient for plant growth and development. Iron deficiency is widely existing in plants growing in neutral or alkaline soils. However, the normal growth and development of plants need to maintain the balance of iron，which is tightly regulated at both transcriptional and post-transcriptional levels. Many transcription factors are involved in the regulatory network of iron homeostasis in plants, among which members of the basic helix-loop helix（bHLH）family are essential for iron homeostasis. In this review, key bHLH transcription factors that regulate iron homeostasis are summarized, and the mechanisms by which these transcription factors regulate iron homeostasis in plant growth and development are reviewed, aiming to provide a theoretical basis to uncover the regulation of iron homeostasis in plants.

Key words: iron deficiency, basic helix-loop helix family（bHLH）, Arabidopsis thaliana, rice

LI Yu, LI Su-zhen, CHEN Ru-mei, LU Hai-qiang. Advances in the Regulation of Iron Homeostasis by bHLH Transcription Factors in Plant[J]. Biotechnology Bulletin, 2023, 39(7): 26-36.

Figures/Tables 4

Fig. 1 Alignment of the bHLH domain of iron-regulated network main proteins The bHLH protein mentioned in the text and the typical human protein MAS with bHLH protein characteristics were selected in the figure. The shaded boxes represent the DNA binding alkaline region and two α spiral and a circular region

Fig. 2 Fe homeostasis regulation in Arabidopsis

Fig. 3 Phylogenetic tree of bHLH TFs regulating Fe homeostasis in Arabidopsis and rice（Oryza sativa）

Fig. 4 Fe homeostasis mechanism in rice

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