MAPK11 regulates seed germination and ABA signaling in tomato by phosphorylating SnRKs.

Jianwen Song, Lele Shang, Xin Wang, Yali Xing, Wei Xu, Yuyang Zhang, Taotao Wang, Hanxia Li, Junhong Zhang, Zhibiao Ye

Journal of experimental botany 2021 Feb 27

filter terms:

Seed germination is a critical stage in the plant life cycle and it plays an important role in the efficiency of agricultural production. However, our knowledge of the mechanisms that regulate seed germination remains limited. In this study, we identified a novel gene, MAPK11, that encodes mitogen-activated protein kinase 11; its expression was significantly higher in seeds of tomato varieties with a low optimum germination temperature than in those with a high optimum germination temperature. In tests at 25 °C, overexpression of MAPK11 in an accession with optimum germination at 25 °C resulted in a decrease in germination, whereas RNAi of MAPK11 in an accession with optimum germination at 15 °C resulted in increased germination. Furthermore, we found that lines overexpressing MAPK11 exhibited hypersensitivity to ABA during germination. These observations were at least partially explained by the fact that MAPK11 up-regulated both NCED1 expression and ABA biosynthesis, and that it also affected ABA signaling and negatively regulated germination by influencing the phosphorylation of SnRK2.2 in vivo. In addition, we found that MAPK11 interacts with and phosphorylates SnRK1 in vivo, thereby potentially inhibiting its activation. SnRK1 interacted with ABI5 and suppressed the transcription of ABI5, thereby affecting ABA signaling and the regulation of germination. Our results demonstrate that ABA signaling in tomato is affected by a mechanism that depends on MAPK11 phosphorylating SnRKs, and this ultimately influences seed germination. © The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Citation

Jianwen Song, Lele Shang, Xin Wang, Yali Xing, Wei Xu, Yuyang Zhang, Taotao Wang, Hanxia Li, Junhong Zhang, Zhibiao Ye. MAPK11 regulates seed germination and ABA signaling in tomato by phosphorylating SnRKs. Journal of experimental botany. 2021 Feb 27;72(5):1677-1690