MYB70 modulates seed germination and root system development in Arabidopsis

• Published in: iScience Vol. 24; no. 11; p. 103228
• Main Authors: Wan, Jinpeng, Wang, Ruling, Zhang, Ping, Sun, Liangliang, Ju, Qiong, Huang, Haodong, Lü, Shiyou, Tran, Lam-Son, Xu, Jin
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 19-11-2021; Elsevier
• Subjects: Biological sciences; Cell biology; Plant biology; Plant Genetics; Plant histology; Cell biology; Plant biology; Biological sciences; Plant Genetics; Plant histology
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2021.103228

Crosstalk among ABA, auxin, and ROS plays critical roles in modulating seed germination, root growth, and suberization. However, the underlying molecular mechanisms remain largely elusive. Here, MYB70, a R2R3-MYB transcription factor was shown to be a key component of these processes in Arabidopsis thaliana. myb70 seeds displayed decreased sensitivity, while MYB70-overexpressing OX70 seeds showed increased sensitivity in germination in response to exogenous ABA through MYB70 physical interaction with ABI5 protein, leading to enhanced stabilization of ABI5. Furthermore, MYB70 modulates root system development (RSA) which is associated with increased conjugated IAA content and H2O2/O2⋅− ratio but reduced root suberin deposition, consequently affecting nutrient uptake. In support of these data, MYB70 positively regulates the expression of auxin conjugation-related GH3, while negatively peroxidase-encoding and suberin biosynthesis-related genes. Our findings collectively revealed a previously uncharacterized component that modulates ABA and auxin signaling pathways, H2O2/O2⋅− balance, and suberization, consequently regulating RSA and seed germination.
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•MYB70 regulates seed germination by enhancing ABA signaling via interaction with ABI5•MYB70 activates the IAA conjugation process by upregulating GH3 genes expression•MYB70 mediates root growth via repression of PER genes•MYB70 negatively regulates suberin biosynthesis in roots
Biological sciences; Cell biology; Plant biology; Plant histology; Plant Genetics