AtHB7/12 Regulate Root Growth in Response to Aluminum Stress

• Published in: International journal of molecular sciences Vol. 21; no. 11; p. 4080
• Main Authors: Liu, Yang, Xu, Jiameng, Guo, Siyi, Yuan, Xianzheng, Zhao, Shan, Tian, Huiyu, Dai, Shaojun, Kong, Xiangpei, Ding, Zhaojun
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 07.06.2020; MDPI
• Subjects: ABC transporters; Abscisic acid; Acidic soils; Aluminum; Aluminum - metabolism; aluminum stress; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; AtHB7/12; Biosynthesis; Cell Nucleus - genetics; Cell Nucleus - metabolism; Cell Wall - genetics; Cell Wall - metabolism; Cell walls; Crop production; Gene Expression Regulation, Plant; Genes; Genetic analysis; HD-Zip I transcription factors; Homeodomain Proteins - chemistry; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Mutants; Phenotypes; Plant Roots - genetics; Plant Roots - growth & development; Plant Roots - metabolism; Protein Multimerization; Proteins; Resistance factors; Roles; root; Sorghum; Stress, Physiological; Toxicity; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; yeast two hybrid; AtHB7/12; HD-Zip I transcription factors; aluminum stress; root; yeast two hybrid
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21114080

Aluminum (Al) stress is a major limiting factor for plant growth and crop production in acid soils. At present, only a few transcription factors involved in the regulation of Al resistance have been characterized. Here, we used reversed genetic approach through phenotype analysis of overexpressors and mutants to demonstrate that AtHB7 and AtHB12, two HD-Zip I transcription factors, participate in Al resistance. In response to Al stress, and displayed different dynamic expression patterns. Although both AtHB7 and AtHB12 positively regulate root growth in the absence of Al stress, our results showed that AtHB7 antagonizes with AtHB12 to control root growth in response to Al stress. The double mutant displayed a wild-type phenotype under Al stress. Consistently, our physiological analysis showed that AtHB7 and AtHB12 oppositely regulate the capacity of cell wall to bind Al. Yeast two hybrid assays showed that AtHB7 and AtHB12 could form homo-dimers and hetero-dimers in vitro, suggesting the interaction between AtHB7 and AtHB12 in the regulation of root growth. The conclusion was that AtHB7 and AtHB12 oppositely regulate Al resistance by affecting Al accumulation in root cell wall.