title: MADS-box transcription factor AGL21 regulates lateral root development and responds to multiple external and physiological signals.
abstract: Plant root system morphology is dramatically influenced by various environmental cues. The adaptation of root system architecture to environmental constraints, which mostly depends on the formation and growth of lateral roots, is an important agronomic trait. Lateral root development is regulated by the external signals coordinating closely with intrinsic signaling pathways. MADS-box transcription factors are known key regulators of the transition to flowering and flower development. However, their functions in root development are still poorly understood. Here we report that AGL21, an AGL17-clade MADS-box gene, plays a crucial role in lateral root development. AGL21 was highly expressed in root, particularly in the root central cylinder and lateral root primordia. AGL21 overexpression plants produced more and longer lateral roots while agl21 mutants showed impaired lateral root development, especially under nitrogen-deficient conditions. AGL21 was induced by many plant hormones and environmental stresses, suggesting a function of this gene in root system plasticity in response to various signals. Furthermore, AGL21 was found positively regulating auxin accumulation in lateral root primordia and lateral roots by enhancing local auxin biosynthesis, thus stimulating lateral root initiation and growth. We propose that AGL21 may be involved in various environmental and physiological signals-mediated lateral root development and growth.
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Lin-Hui
authors.initials: LH
authors.lastname: Yu
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Zi-Qing
authors.initials: ZQ
authors.lastname: Miao
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Guo-Feng
authors.initials: GF
authors.lastname: Qi
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wu
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Xiao-Teng
authors.initials: XT
authors.lastname: Cai
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China.
authors.forename: Jie-Li
authors.initials: JL
authors.lastname: Mao
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui Province 230027, China. Electronic address: xiangcb@ustc.edu.cn.
authors.forename: Cheng-Bin
authors.initials: CB
authors.lastname: Xiang
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000254:growth & development*; D030821:Plants, Genetically Modified / Q000254:growth & development; D015398:Signal Transduction
chemical_list: C465130:AGL21 protein, Arabidopsis; D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D026161:MADS Domain Proteins
keywords: AGL21; MADS; auxin; lateral root; nitrate; root system architecture; sulfate.