MYB70 modulates seed germination and root system development in Arabidopsis
Jinpeng Wan,
Ruling Wang,
Ping Zhang,
Liangliang Sun,
Qiong Ju,
Haodong Huang,
Shiyou Lü,
Lam-Son Tran,
Jin Xu
Affiliations
Jinpeng Wan
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Menglun, Mengla 666303, China
Ruling Wang
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China
Ping Zhang
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; College of Horticulture, Shanxi Agricultural University, Taigu 030801, China
Liangliang Sun
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; College of Horticulture, Shanxi Agricultural University, Taigu 030801, China
Qiong Ju
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; College of Horticulture, Shanxi Agricultural University, Taigu 030801, China
Haodong Huang
State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
Shiyou Lü
State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
Lam-Son Tran
Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam; Institute of Genomics for Crop Abiotic Stress Tolerance, Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA; Corresponding author
Jin Xu
CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China; College of Horticulture, Shanxi Agricultural University, Taigu 030801, China; Corresponding author
Summary: 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.
